LMAO.. the trick on mine is to open the throttle a bit more then the Start Indicator mark on the first start of the day. The other trick is not to have the tank too low if you're working on them in the garage. The old fuel pumps need frequent maintenance...
I always find your videos entertaining, and informative. Good job on the diagnostic procedures. I have a 7.5 mercury comet, so I really just stopped by to see the similar motor being pulled apart before I get into mine. The video was very helpful, and well worth watching. Thank you.
Even though nothing seemed to be wrong with the Merc, I still learned something about the inside of outboards. It will help me with my 20 HP mercury THANKS FRIEND
Great sense of humor, I love your approach to trouble shooting, slow and easy and when in doubt check elsewhere, just because your taking the engine apart for the first time doesn't necessarily mean it was put together properly in the first place, thanks for the video and enjoy your ride : )
Just found your channel. You seem like a knowledgeable guy. I myself am 33 and a self employed marine tech. I mostly do a lot of newer fuel injected stuff but see the old carbs from time to time. Anyways I look forward to watching your videos
Thanks Joel, glad to hear you have chosen to join us. Feel free to comment if you ever do anything differently, love to hear new ideas for other techs.
Mate you are a legend this video helped me figure out which old unmarked Mercury motor I've got now going to have a crack at replacing the impeller. Cheers!
had the same issue with my old little mercury, when i cut some of the wires under flywheel they were filled with corrosion, just replaced wires and been starting like new, thanks for posting!
Hi Stu, great video. I had a mate drop around to me to fix (as I am a mechanic ) a Mercury 40 a single cylinder 4hp. What memories this video bought back to me!! Mercury in their wisdom back in the 70's and early 80's from memory decided to add an extra zero to their hp range. Thanks for the laugh about using an non impact socket! P.S.T shirt turned up the other day. Cheers
I've owned a few of those and the 7.5 hp. I never left the fuel line connected over night or it would take for ever to start. I'd choke it and as soon as it started push it in, it was a bugger to fire up otherwise. The bolts on them snap easily and its lots of fun to put the lower back on. I used to set the power head upside down and strap it to the bench leg, then slide the lower in. If anything is moving about you'll never get it lined up.
Hey Rene, I too had a fair bit of trouble getting that lower unit back in yesterday. It got there in the end but it didn't exactly slide in first time. ;)
They are very easy to flood. One or two pulls maximum with the choke, then a half dozen pulls with the choke off and the throttle in the start position. That's usually enough to clear it, however if you pull the cowling off you can manually actuate the throttle to wide open. By the time you fussed around and done all that any of that excess fuel should have evaporated off.
Someone may have mentioned this but just in case... The water pump impeller. There were missing parts and with this and a few other engines it is vital that you find the broken and missing impeller pieces. With this engine there is a small area at the bottom of the power head where water psi probably pushed the broken pieces up, into the tube and then into the area under the power-head. These pieces are in a small area that needs cleared because it can clog water passages and then you overheat because water flow is stopped or severely restricted in vital areas. I learned in my shops long ago that engines die from this. When people have this issue and sell the engine, the new mechanic checks impeller and all the pieces are new since it is a new impeller. They then fail to understand the overheat issues and never again has a good running machine. So anyways, even if u have to strip the engine down, find those parts
@@yesnothanksplease It depends on what happened. I actually have two of these here at my place at the moment lol (along with 27 other outboards ranging from 7 to 300 hp.) Both of mine had similar issues, Impeller fins broken off. First thing you can do is feed a still fire up the water tube with a small hook end and see if you can catch the pieces, ... IF they were stuck in the tube you may get lucky. The big thing is to make sure you get all of them. If this does not work, you have to pull the powerhead off the midsection. IT is easy with this engine, just a few nuts n bolts and it is up. There is a passage area under the powerhead where the pieces should be located. You can look down the tube from the mid section to make sure the water feed tube is clear, 90 percent of the time I find the fins here, on the rare occasion I do not, I pull the water jackets and thermostats out to make sure they are not lodged in the thermostats and continue until I have cleared all the water passages from intake to exhaust. There are times small enough pieces may work all the way through but that is rare.... Just be careful. You will know if you missed them if the engine runs with hot spots. Best to you and sorry I did not know you had asked a question.;
Great video. I picked up a small boat with one of these motors on it. It ran for us up until the fifth outing and the motor just died, down river from the boat launch of course, lesson learned. Went through most of what you did. However, the area where the water pump is had a white milky oil/water foam in it. I am not sure how that go in there. The lower unit where the grease is was fine and not contaminated with water. I determined it was getting fuel into the combustion chamber. Cleaned the carb and replaced the fuel screen and the gaskets under that. Checked float and needle valve and reassembled. Replaced the spark plugs. Initially it would not start, noticed I had a spark plug wire off and tried again and it started. I really like the detail you put into this video. I still don't know the oil got into the water pump area and mixed with any water in there. But that is the limit of my knowledge of outboards so far. It's and old motor, 1972, and like you commented in the video, how much do you put into these older motors unless you are very sentimental.
Sounds like maybe the driveshaft seal below the water pump has failed causing your oil problem. It is tough with these older outboards as the cost of repair can very quickly exceed their value which is why most professional mechanics won't touch them.
In the 60s and most of the 70s, Mercury used to add the extra Zero to their HP rating. So the engine was actually an 11, but merc said it had 9.8hp so as to skirt several regulations regarding Licencing and HP restrictions.
I have a game Fisher 9.8 it’s the same motor as the mercury the timing is set by arrow marks and the plastic gets old and stretches a little bit making it hard to start so every year I check it before the season. A good form to check out is called tin boats they have manuals you can download pdf. I hope it helps you and thanks for helping others stay on the water.
Thanks again Stu,Had to separate an old merc 6 hp gearbox and i couldnt do it.Decided to give it a harder hit after watching this (succeeded)and sure enough that gearbox egg spline was rusted stuck. I was contemplating throwing the motor away prior..Cheers
Hi Stu, A friend had a 4 stroke lawn mower with a no start condition, so I said I’d take a look at it. I had fuel, air, and spark, but not so much of even a hint that it was trying to fire up. There was a bit of corrosion on the stacks of steel plates that make up the ignition coil, nothing uncommon, and everything gaped proper. The ohm test of the coil was on the high side of normal parameters. A new coil was in stock at the local toro dealer. It was affordable, and a new design that had a module built into it. So i figured why not give it a shot. I really haven’t found anything wrong, other than a bit high on the ohm spec for the coil. Installed and gaped the coil, and it fired up the third pull. I mowed my lawn with it and had a total run time of two hours. Ran beautiful. Loaded it the pick up truck, brought it back to her, and said your good to go. That weekend she called me and said it was mowing great and half way through her yard, it just stalled, and no start. I thought she was joking. A weird thing to be running great and just stop. I picked it back up, and found nothing wrong. Strong spark, good fuel, everything checking out. It wasn’t a vacuum issue from the fuel cap. So for a lack of what else it could be i decided to pull the flywheel. I found nothing wrong. No cracks, no corrosion, everything reasonably clean and within adjustment. I was stumped. With nothing more to check, I put the fly wheel back on, re gaped the coil, hooked all the wires and plug lead back up. My wife said “is it fixed?” And i said “nope, i cant find anything wrong.” She said “well give it a try and see if it starts.” (It was getting late in the evening) I just made a gimmace face and said “ok”. Started first pull and hasn’t stoped mowing her lawn in two years since. So I don’t know what i did, or why it stoped running. But for some reason taking the flywheel off, and putting back on was just what that engine needed. Keep up the good work Stu, -Kris Ps- your website for ordering t-shirts is down today. I gotta get a couple of them. One for working in, and for on the town!😬
Hey Kris, yep, it certainly goes that way sometimes. Even though it is working it is frustrating to not know what was wrong as you don't trust that it won't happen again. Thanks for reminding me of the problem with the shirt site, all fixed up now. :)
My favorite part was " use a non impact socket so people will have something to complain and talk about " love your humor , another great video though keep em coming
Love your videos. I hit my lower unit with mallet and broke off a small peice. My lower unit was being held up by the copper pipe stuck in the fitting.
Good video mate I've been rebuilding my 1987 yamaha 60 autolube for the past 3 weekends everything that could go wrong did snapped gearbox bolts snapped water pump bolts snapped most bolts lol but it's nearly back together and should be out on our boat next weekend but your videos have helped A lot pal.
Dangar Marine I've just commented on another video Stu about the gear selector rod, It came out of the lower unit when taking it off and I didn't realise is wasn't ment to at the time now as you know I can't get the rod back into the dog clutch to get it out of forward do you know any way to do it other than taking the lower casing to absolute bits? Thanks for any help dude
Ha! For once I actually wasn't joking! That screwdriver has a shaft that goes all the way through the handle to a metal plate at the end so it can be hammered without the handle shattering. :)
Well what a result. Great to see. My experience with Mercury outboards of that size has been they sound like guys in the factory threw in nuts and bolts before they sent them out. That actually sounds sweet . That said I'm a Yammy & Honda man myself . Thanks for posting
It did sounds rather sweet (surprisingly!) once it started running. I am more into Japanese motors too, but this one sounds like it does have a bit of life left in it.
Great video Stu!! Very cool to see you work on an older Mercury. That is either a 1976, or a 1977 model...those were the only two years that Mercury used that decal scheme. I happen to have it's "little brother" a 1976 7.5 hp model. Put many enjoyable hours on Her in the 1970's on a Lake in Northern Wisconsin Here in the States, and she still looks almost new :)
Glad to be of help on the age :) Growing up in Wisconsin in the states, I am somewhat of a vintage Mercury buff, and they used that striping for only 1976 and 1977. I had a 1977 85hp Merc (that was a Brute) with the same coloring. The little 7.5 in my opinion always seem to "punch above its weight" it seemed in power output. Back then, on identical cottage lake boats, it would out run our neighbors 9.9 Evinrude..he was not pleased :) Again Stu, thanks so much for posting this one!
Gday mate this is the first engine i ever had as a project to work on got it to run reasonably well by the end put new parts on it ect ect and sold it for 10 dollars my loss but got some experience i think it was the earlier version old blue band motor didnt have the 110 on it , good video and smart move call it a win and give it back .
I think having one of the those projects that loses you money is a great way to learn. I would recommend anyone to find an old outboard they can experiment on if they are interested in getting their skills up.
Stu it was that squirt of " Start Ya Bastard" that done the trick....its great stuff i love it...oh the the attention of coarse.....great job mate.....Brett
ALL 2 stroke Mercury's are hard starting. I've had two now, and sold them both, I hunt Waterfowl in Upstate NY, and the colder it gets, the harder they start. Have since switched to Evenrudes.
if you have a spare spanner of the slightly too small size, you can grind it lightly with a grinder and thin wheel or file, just something I have done in the past.
Hi Stu, you said you where going to do a merc video but was surprised you had a 110 9.8hp like my son's that I did a few videos on this past summer. cool little engine. I too was surprised being a old American outboard I had to use standard sockets and wrenches on. lucky too to get the parts online for it. The carb was weird with fuel coming out the carb choke screen bolt hole. I fixed that when I put the bolt back in with a small oring. didn't have one but put it in anyway. it stopped the leak. Anyway after that installed new lower unit seals/orings and impeller housing it worked great for them the rest of the summer. if you have time watch my 110 9.8hp videos. keep the stick on the ice mate
I have a syringe (no needle) with fuel in it. Great diagnostic tool. Squirt some in the air intake intake, see what happens. If no joy, squirt some in the spark plug holes, and give a few pulls. Tells you quite quickly if you have a fuel, or a spark problem.
I had a 110 Merc when I was a kid but it was a bit older than this on as it still had points. The motor started great when it was cold and only required a three inch pull (100mm) to start once it was warmed up. I wish I still had that little beast as I just picked up a small skiff (tinny) last year that it would have been the perfect motor for.
Small world Stu..i just inherited one of these and searched diagnosing electronics for them and here we are..looking to add it as an auxilliary on my offshore tinny so just researching why its a no sparker..Hope the Gemmy is together and aok now.
I enjoy your videos and sense of humour.👍I would like a quid for every time I fixed something without understanding why.😳Although you did lengthen the starting cord which would effectively warm up the combustion chamber ( albeit it that is grasping at straws) and you resolved the steaming overheating issue with the new impeller. Keep on keeping on.😀
Lol at 12min 45 sec you claim “it’s now early Friday morning” And you have what looks to me a beer in your hand. Brilliant I take my hat off, I thought us Kiwis were the early drinkers. Love your vids mate very good
I love your vids I actually have on of those 110 mercury motors had a bad coil that "leaked" if i put rubber between the coil and the motor it would run fine but once it was properly mounted it would spark over to the motor instead of the plug sparking put new coil on now it runs good . Nice to see how it all comes apart
Ah, that's interesting to hear. I couldn't see any spark leak but it would have been interesting to spray a bit of water over it and see how quickly it started to lose spark. Thanks for the tip!
Realized you were new to Mercury when you were thinking "Head Gasket" & Reed valve at the top of that era motor. The round reed block is always under the carb and the pattern usually is between two cylinders.....twins have one, four cyls have two and the inline 6's have three. (Like 3 twins stacked) ALL those old mercs are "clam shell" where the entire cylinder including the combustion chamber along with the upper half of the crank case are in one casting....one of the reasons they are so rugged, but also harder to modify compression ratio for more torque, the bottom half of the crank case has the carbs......with the intake port to the reed blocks that feed two cylinders. :) Can swap out those reeds with aftermarket reeds for more RPM's if your into that type of thing. So good video, you scared the crap outa me when you started wandering and made me wonder if all the years I have worked on Merc's I was seeing something that wasn't there....or was it? reality challenged...but by the end all was right again. :)
Interesting you call it a 'clam shell' design. When I was in the motor trade (a looooong time ago) I had to rebore a 'blind end' Bugatti six cylinder block one day. That was the same as what you call a 'clam shell'. The head, cylinder block and top half of crankcase were all one casting. Very intricate and amazingly well made.
As were Miller/Offenhausers . I build chainsaws and build "warmer" than stock saws. In that world a clam shell design as with many of the home owner saw is defined as a casting including the combustion chamber, cylinder, and upper half of the main bearing pockets as one side and the lower half of the crank case the other. The reason that's not as desirable in that paradigm is how hard changing compression is. NOT a bad thing in some applications! Typically its easy to either "deck" the base of a cylinder or remove some material from a head to play the compression game. But with a "Clam Shell" design ( Chainsaw world terminology) its very difficult to either deck the cylinder to lower it relative to the pistons or plane a head..it doesn't HAVE one! ( One of the reason I knew this guy wasn't a mercury guy ) About the only way to modify these are things like changing x-sectional area's and reed valves. Port timing...maybe. :) But your stuck with the combustion chamber geometry.....hence all added up. Clam Shell. Very rugged. Most of what I post here is for my community..:)
Yes, most motors around here are either Honda's or Yamahas, and never particularly old as they get used 365 days a year in salt water so generally get replaced by the time they are about 10 years old. It's always interesting having a poke around an unfamiliar motor though to see other ways of doing things. Thanks for the info!
1.ohh man.. you need to take apart the whole thing to take out the reed housing (if you do that ,don't worry about that you won't find sealing in that reed housing, it's designed that way) 2.don't worry about the head gasket either because the cylinders and a head is the same complete block (don't know how you called this type) only the water jacket cover what you can take off, but if not leaking... 3. 115-110psi is perfectly fine because it's a domed cross-flow design with decompressor ports 4. the screw what you are missing from the bottom of the leg is just for the plastic screen filter 5. for cold start issues -> sealings (bottom, top) ; correct carb fuel level; working choke plate
Thanks György, good to hear from someone so familiar with these motors. Yes, I'm not sure what you call that type of block either, but good to know only the water jacket cover has a gasket, one thing we can rule out. I might order than plastic screen then, debris might have been part of why the impeller got chewed up so badly. The choke plate definitely works and I wasn't the one that cleaned the carb so I might go back in and check that float level. Thanks for the information! :)
Dangar Marine Do you remember Stu, when I asked you on the head gasket video, if you ever worked on a "headless" outboard? You're reply was "I can't say I have." Well, now you can say you have!! I told you if I was ever going to rebuild it, I would need to find a knowledgeable machine shop that can bore "blind cylinders". It's cool you now see one😊
My merc 1987 70hp is a 3cyl, with blind cylinders. I had to ship the block halfway across the country (Canada) to a machine shop that could do the bore job. Very specialized, as very few motors use blind cylinders, and even fewer shops can bore them. It was pricey.
haaaa,good one mate!,you knocked the dust off the old Merc,she just needed some love.I have a couple old Mercs.A 1970 4hp and a 1984 4.5hp and i love them.I would sooner work on and own a Merc any day then an old JohnRude.Keep up the videos. If ya ever make it to NS Canada i will buy ya some beers because i owe you for some easy fixes on some of my other motors.
Sometimes just taking them apart and putting them back together fixes something you didn’t understand.. it happened to me with a carb once. An outboard bogging down, try to clean the carbs and they are perfectly clean. Put it all back together, it runs flawlessly.
Ha...Land Rover electrics playing up ? Never !! Good to see Friday morning Coops to celebrate the weekend ride too mate. I have the same outboard in 7.5..probably a detuned 9.8 I'd say. Good vid Stu
You and your channel has been a bundle of info for me! Wondering is there a required set depth on the lower end seals of an eighties 9.9 merc. I mean the ones that have to be pressed in.
Not sure on that model. Often those seals are just pressed in until they are hard up against a lip but unfortunately sometimes there is a custom tool to get the correct depth.
hey stu,all those old small merc's were hard starting bastards in my experience!..its even worse when its cold outside!i knew a guy that actually gave one away because he hated it so bad!
hometownguy71 My dad got rid of one for being so hard starting cold. He was used to his old 9.9 Johnson starting on the second pull regardless of how cold it was outside. He found him a nice 15hp Johnson and lived to be 82 but never wore it out.
Thanks for another informative vid, Stu. Love your deadpan delivery..."It's important to use a non-impact socket..." LOL. I have the same vintage Merc in 7.5hp form and they can indeed be finicky. They are famous for cooking the ancillary ignition wiring over time. Check that the insulation hasn't gone all crumbly...As for 110 the designation on the side, could be a couple of possibilities...Every once in a while Mercury Marine would make a design change to a horsepower range and rename the engines. They did that with the 40 horse motors and....voila...402 designators began to appear. Also, not sure about Down Under but in Canada and the US, any boat with 10hp and above requires license numbers to be applied for and then displayed on the hull. Manufacturers then got very coy in the seventies about producing engines in the 9.9, 9.8 hp range when they were really fully 10 hp. The 110 might be a wink to that. Anyway, very entertaining as usual. Have a great bike trip!
Not quite correct, any boat with a motor here in California has to get license numbers. But back in New York, the 10 hp was a limit on many lakes, hence the change from 10hp outboards to the 9.5, 9.8, 9.9, etc. Many folks took a 15 and put a 9.9 cover on it... :) I'd never heard of any designation of a Mercury that eneded in other than zero, but accept that you're correct with the 402. But I don't think that was on the cowl, was it? EXCEPT the 110 engines, the numbers were 10 times the hp, so a 75 was 7.5, 1100 was 110hp, etc. It would be interested to see if the motor actually developed 11hp, vs. the "rated" 9.8, which would make the numbering correct. RichE
Interesting about CA.... I stand corrected although here in Ontario you don't (or at least didn't) need a license under 10 hp when these things were new. We had one of the 402 Forties....could have sworn it was on the cowl....but again, that memory is forty plus years old...so many fours!!
Interesting info guys. I had always presumed that 10HP must have been a cutoff point for registration or needing a license somewhere in the world. Here it is 5HP for registration and travelling over 10 knots for a license, no matter what the boat is capable of.
Ten knots...I recall bolting that little Merc onto a wee slip of a homemade boat when I was about 15. Not much more that a 4x8 sheet of plywood. Zero freeboard, no strakes for directional control...I'd sit on the floor with my back against the transom, tiller jutting out beside my left ear....fuel tank between my legs....just screaming down the lake for all it was worth, which was surprisingly quick. Turning was interesting. Without the aforementioned strakes when you pulled the tiller to turn, the boat crabbed....and just kept going straight. Turning circle at speed was about 200 feet. Utter death trap unless it was flat calm and no traffic....and the most fun I've had on the water I can remember. :-)
I had a 1968-70 110 and it was a legend of a motor, always started no matter what abuse. Eventually crumbly wiring and decay made it a bit too chancy for use in remote locations. Newer fuels varnished the carb up readily making for cranky starts. Check the impellor regularly, a bugger to grind the old one off if it gets corroded onto the shaft.
Hi Stu, Happy Friday or probably Saturday for you by now. Good news on my Yamaha kicker motor. It would not start again a couple weeks ago after putting in the new non-ethanol fuel. Checked for spark first and as I thought the carb was plugged up again. Took it out, cleaned it and started right up today. I think after Thanksgiving I'll make a video on how to put the lower shift rod back together on this unit. It's a royal pain for access if you have ever worked on a small 4hp yamaha you'll know what I'm talking about. Tim
when removing the lower unit....I remove that lower nut first above the propeller. the upper nut. I place a thin piece of hardwood or aluminum flat bar between the top of the nut and the surface above it. then I loosen the nut. it acts as a wedge forcing the L/U down. I never tap on the anti-cavitation plate. They are too fragile. I watched your video because I'm gathering parts to replace the corroded wires . I will install new electrical parts under the flywheel. I bought my 110 new in 1977 and after 40 years it's time I'd say ! I replaced the switchbox about 6 years ago. It still ran OK but the side of the block had something like honey on the side of it. I showed it to the president of my antique outboard motor club, a 30 year Mercury dealer. There is a goo like epoxy that seals the integrated circuit board inside the switch box. that stuff melts out. Another guy at the outboard meet looked at my switch box melted too. he worked at Mercury 42 years and told he was head of quality control when Mercury machined 9800 Merc 110 engine blocks in ONE batch process ! Anyway he said it was an epoxy to seal the electronics. Before I got the new switchbox we tried putting a 4 HP Mercury GNAT switchbox on it. It is said it is the best electronic switch box Mercury ever made. The 110 started on the first pull. I put the engine in gear and started to drive the boat away but it only went to a fast idle speed. when I twisted the throttle wide open the engine never sped up. Back at the dock I had it in neutral and would it up wide open and slow it down and it would go - ran-nan-nan-nan-nan just like a dirt bike. It had a real crisp sound. Well the Merc dealer ordered me a new switchbox and we put it on and it runs perfectly. it always take 3 pulls to start. I only use no ethanol gasoline at 89 octane and usually I double up the oil and run 25:1 because that what I use in my Mark 10, Mark 28, and Merc 250 - all of them are automatic transmission outboards 1957-1962. I tried some 100LL aviation gas but I didn't like it. It turned my spark plugs white and I looked at the piston crowns and they were spotlessly clean in a 1958 outboard. I'm a little scared of that stuff because it has some lead in it
Great vid Stu. I was however looking forward to you finding the exact cause. Were you able to bring back the fault? Could the high voltage have been spilling somewhere? Cracked spark leads? Bad caps? I think I read once that cranking in dark conditions may reveal something like that. I am thinking that you may have moved something (maybe just slightly) that made the cause dissappear. Intermittent faults can be annoying.
I was hoping to find the cause too. Taking the pull start off does mean bending the wires for the coils so maybe that is where the fault lies. If you have high voltage leaks you can normally hear it arcing as well, but yes, running in the dark and spraying water on the leads can certainly help find the problem.
Ok. I haven’t tried nor heard of the water spray method, but I know it will help transfer the high voltage to something like my hands if probing for current or simply not being carefull enough :-) On another note - I just got to think of the proces caused by broken screws/bolts and having to drill them out and rethreading, maybe even installing an insert. It must have happened to you a few times as well. Just wondering if you have some preferred methods in the whole proces of being gentle with existing threads. Also on choice of inserts types/brands and choice of material for the insert. Maybe you find it interesting enough for a video. I have found a few things that work for me but I am very happy to harvest on other peoples experience. For me when screw has snapped) (the real # 1 - don’t rush!) #1 - always carefully hammer center point and start of with 3 mm drill bit. # 2 - drill out with cobolt drill bits - they are hard. # 3 - only drill to a depth of max. 8-10 mm to avoid a stuck drillbit then change to a drill bit 0.5 mm larger. Repeat until at the needed hole size then repeat the proces. No one wants a stuck and possibly broken drill bit. # 4 - If trying to salvage existing aluminum threads with a little leftover stainless steel inside the hole, I will be eager to vacuum out every 1-2 turns when tapping the threads (meaning a total removal of tap every time) plus everytime I feel it could remove some SS. On inserts I have only used the non-removable coil type from Helicoil (stainless). They seem to do the job. I am not sure if there is a better choice?
humleridder my 9.8 supposedly “just needed a new exhaust gasket” when purchased. Come to find the exhaust plate was cracked, and 4 bolts were snapped off. I was able to remove one by welding a nut on the end of it and backing it out. One other one came out with an easy out from the 80s, very old bits. The last two were drilled and tapped, but did not work. I took it to a buddy who used time serts which are a million times better than helicoil and will withstand the time. Some new gaskets, a new plate and she was back up in no time.
These motors were and are still very common in my area of the Northeast USA. They must have been the perfect combination of price and power for rowboats for decades. They also last forever, but the impeller is hard enough to fix that lots of them end up in some outbuilding or shed in deep storage. Great Video!
Stu, I have had reed/rotary valves 'glue' to the base because of old/dried out two stroke oil sitting on them. The clean up was a cup of diesel to flush things out - a suggestion by a mates father- and we ended up with three RD250s to ride for a few weeks. Loved the 9/16ths of 2 halves an inch - where did you learn that one? Sounds like an Arn-ism- and I haven't heard that line for 40 years!Hope the ride went well.
Hey Ron, good tip about checking for the reeds being stuck down. They are often inspected for their ability to close and seal but not so much for their ability to open. That measurement is just one I made up, it's always how imperial measurements sound to me, way more complicated than they need to be!
My grandfather used to mumble about imperial measurements all the time and had a comment very similar to yours. But his favourite was always 'four fifths of bugger all'.
Curious? Ive seen other outboards started by means of a portable drill. Can a 110 be started in this manner? It would just be a fun video. All 110 fans would be greatful.
Just bought a 1982 9.8 today. After cleaning out the mud wasp nest in the electrical generation area under the flywheel, she started right up and idled for a few seconds on Starting fluid. Can't do anymore until the linkage that connects to the carb arrives. Only part besides the cover in front of the carb butterfly missing. I appreciate you showing me where the reeds are. Was wondering. Thanks.
Another great video Stu. Checked all your vids but unable to find out whether or not water from tell tale should warm up when flushing motor after 4 or so minutes. Plenty of water pissing out of tell tale. Maybe a cooling system troubleshooting quick vid with this and some other points for us amateurs? Cheers mate!
Thanks mate. This video will show you want is going on with the tell tale ruclips.net/user/edit?o=U&video_id=joEQChcZl2A Often on outboards the tell tale water doesn't actually go through the engine water jackets but it will still get warm from the whole block conducting heat into the exhaust cover.
Love your videos! The 110 is the number of pulls required to start. You, mate, have a gift and I am a fan for sure.
Thanks Kevin. It does sound like these 110s can be tricky to start. Glad it's not just me!
LMAO.. the trick on mine is to open the throttle a bit more then the Start Indicator mark on the first start of the day. The other trick is not to have the tank too low if you're working on them in the garage. The old fuel pumps need frequent maintenance...
Yep those old Merc's had a lot of sticky/plugged fuel pumps or worn/cracked impellers too.
Kevin Wilson lol so true. I had a 7.5 that was good for atleast a few hundred pulls.
HAHA this is so true
I always find your videos entertaining, and informative. Good job on the diagnostic procedures. I have a 7.5 mercury comet, so I really just stopped by to see the similar motor being pulled apart before I get into mine. The video was very helpful, and well worth watching. Thank you.
I have GOT to get me a can of "Start Ya Bastard" ... best product name EVER!
I have had so much of that stuff for everything it’s amazing
I'll use that on the mrs
Great video Stu! That motor just needed a hug and a little attention.
Don't we all! ;)
Even though nothing seemed to be wrong with the Merc, I still learned something about the inside of outboards. It will help me with my 20 HP mercury THANKS FRIEND
Hey Ronald, glad the vid helped you. Good luck with your Merc. :)
i love hearing an outboard start purring like a kitten keep it up please
Great sense of humor, I love your approach to trouble shooting, slow and easy and when in doubt check elsewhere, just because your taking the engine apart for the first time doesn't necessarily mean it was put together properly in the first place, thanks for the video and enjoy your ride : )
Thanks Adrien, and good point about not trusting the way it currently is, who knows who last worked on it.
Just found your channel. You seem like a knowledgeable guy. I myself am 33 and a self employed marine tech. I mostly do a lot of newer fuel injected stuff but see the old carbs from time to time. Anyways I look forward to watching your videos
Thanks Joel, glad to hear you have chosen to join us. Feel free to comment if you ever do anything differently, love to hear new ideas for other techs.
Mate you are a legend this video helped me figure out which old unmarked Mercury motor I've got now going to have a crack at replacing the impeller. Cheers!
I have a little 9.8 that I'm doing maintenance on. I wanted to say thanks. That was a great video.
You're welcome Doug, good luck with your motor. :)
had the same issue with my old little mercury, when i cut some of the wires under flywheel they were filled with corrosion, just replaced wires and been starting like new, thanks for posting!
I think wiring could be a good candidate even though it does seem to have good spark. I might have to make a few test cuts and see what I see.
'It's now early on Friday morning' - holding open bottle of Coopers.
Also, congrats on the sponsorship mate!
Thanks Andrew. ;)
Hi Stu, great video. I had a mate drop around to me to fix (as I am a mechanic ) a Mercury 40 a single cylinder 4hp. What memories this video bought back to me!!
Mercury in their wisdom back in the 70's and early 80's from memory decided to add an extra zero to their hp range.
Thanks for the laugh about using an non impact socket!
P.S.T shirt turned up the other day. Cheers
Thanks David. If in doubt I always say add an extra zero. ;) Thanks for buying a shirt, be sure to send me a photo so I can add you to the cool wall!
I've owned a few of those and the 7.5 hp. I never left the fuel line connected over night or it would take for ever to start. I'd choke it and as soon as it started push it in, it was a bugger to fire up otherwise. The bolts on them snap easily and its lots of fun to put the lower back on. I used to set the power head upside down and strap it to the bench leg, then slide the lower in. If anything is moving about you'll never get it lined up.
Hey Rene, I too had a fair bit of trouble getting that lower unit back in yesterday. It got there in the end but it didn't exactly slide in first time. ;)
They are very easy to flood. One or two pulls maximum with the choke, then a half dozen pulls with the choke off and the throttle in the start position. That's usually enough to clear it, however if you pull the cowling off you can manually actuate the throttle to wide open. By the time you fussed around and done all that any of that excess fuel should have evaporated off.
Someone may have mentioned this but just in case... The water pump impeller. There were missing parts and with this and a few other engines it is vital that you find the broken and missing impeller pieces. With this engine there is a small area at the bottom of the power head where water psi probably pushed the broken pieces up, into the tube and then into the area under the power-head. These pieces are in a small area that needs cleared because it can clog water passages and then you overheat because water flow is stopped or severely restricted in vital areas. I learned in my shops long ago that engines die from this. When people have this issue and sell the engine, the new mechanic checks impeller and all the pieces are new since it is a new impeller. They then fail to understand the overheat issues and never again has a good running machine.
So anyways, even if u have to strip the engine down, find those parts
how do you clear it?
@@yesnothanksplease It depends on what happened. I actually have two of these here at my place at the moment lol (along with 27 other outboards ranging from 7 to 300 hp.)
Both of mine had similar issues, Impeller fins broken off. First thing you can do is feed a still fire up the water tube with a small hook end and see if you can catch the pieces, ... IF they were stuck in the tube you may get lucky. The big thing is to make sure you get all of them.
If this does not work, you have to pull the powerhead off the midsection. IT is easy with this engine, just a few nuts n bolts and it is up. There is a passage area under the powerhead where the pieces should be located. You can look down the tube from the mid section to make sure the water feed tube is clear, 90 percent of the time I find the fins here, on the rare occasion I do not, I pull the water jackets and thermostats out to make sure they are not lodged in the thermostats and continue until I have cleared all the water passages from intake to exhaust. There are times small enough pieces may work all the way through but that is rare.... Just be careful. You will know if you missed them if the engine runs with hot spots. Best to you and sorry I did not know you had asked a question.;
For what it's worth ... I learn a lot from your vids.. just want to thank you for what you do
Thanks mate, it all makes it feel worthwhile it people are learning from them. :)
Another great video Stu. You make it look so easy. My Dad had one of those outboards and it was very difficult to start too.
I owned one of these for many years. I was lucky to get a one pull wonder. Wish I still had it with my bad shoulder now.
Great video. I picked up a small boat with one of these motors on it. It ran for us up until the fifth outing and the motor just died, down river from the boat launch of course, lesson learned.
Went through most of what you did. However, the area where the water pump is had a white milky oil/water foam in it. I am not sure how that go in there. The lower unit where the grease is was fine and not contaminated with water.
I determined it was getting fuel into the combustion chamber. Cleaned the carb and replaced the fuel screen and the gaskets under that. Checked float and needle valve and reassembled. Replaced the spark plugs.
Initially it would not start, noticed I had a spark plug wire off and tried again and it started. I really like the detail you put into this video. I still don't know the oil got into the water pump area and mixed with any water in there. But that is the limit of my knowledge of outboards so far.
It's and old motor, 1972, and like you commented in the video, how much do you put into these older motors unless you are very sentimental.
Sounds like maybe the driveshaft seal below the water pump has failed causing your oil problem. It is tough with these older outboards as the cost of repair can very quickly exceed their value which is why most professional mechanics won't touch them.
In the 60s and most of the 70s, Mercury used to add the extra Zero to their HP rating. So the engine was actually an 11, but merc said it had 9.8hp so as to skirt several regulations regarding Licencing and HP restrictions.
Correct! I have a 9.8, as many of the local ponds won't allow 10hp or above to get on their water.
I have a game Fisher 9.8 it’s the same motor as the mercury the timing is set by arrow marks and the plastic gets old and stretches a little bit making it hard to start so every year I check it before the season. A good form to check out is called tin boats they have manuals you can download pdf. I hope it helps you and thanks for helping others stay on the water.
Good to know they have a source of PDF manuals, I'll check it out. :)
...the most valuable videos on the subject on RUclips.... just keep them coming Stu.... Thanks!
Thanks mate! :)
Thanks again Stu,Had to separate an old merc 6 hp gearbox and i couldnt do it.Decided to give it a harder hit after watching this (succeeded)and sure enough that gearbox egg spline was rusted stuck. I was contemplating throwing the motor away prior..Cheers
Glad to hear you got it out. Sometimes your only choice really is to just hit it harder. Corrosion never makes things easy!
Hi Stu,
A friend had a 4 stroke lawn mower with a no start condition, so I said I’d take a look at it. I had fuel, air, and spark, but not so much of even a hint that it was trying to fire up. There was a bit of corrosion on the stacks of steel plates that make up the ignition coil, nothing uncommon, and everything gaped proper. The ohm test of the coil was on the high side of normal parameters. A new coil was in stock at the local toro dealer. It was affordable, and a new design that had a module built into it. So i figured why not give it a shot. I really haven’t found anything wrong, other than a bit high on the ohm spec for the coil.
Installed and gaped the coil, and it fired up the third pull. I mowed my lawn with it and had a total run time of two hours. Ran beautiful. Loaded it the pick up truck, brought it back to her, and said your good to go.
That weekend she called me and said it was mowing great and half way through her yard, it just stalled, and no start. I thought she was joking. A weird thing to be running great and just stop.
I picked it back up, and found nothing wrong. Strong spark, good fuel, everything checking out. It wasn’t a vacuum issue from the fuel cap. So for a lack of what else it could be i decided to pull the flywheel. I found nothing wrong. No cracks, no corrosion, everything reasonably clean and within adjustment. I was stumped.
With nothing more to check, I put the fly wheel back on, re gaped the coil, hooked all the wires and plug lead back up. My wife said “is it fixed?” And i said “nope, i cant find anything wrong.” She said “well give it a try and see if it starts.” (It was getting late in the evening) I just made a gimmace face and said “ok”. Started first pull and hasn’t stoped mowing her lawn in two years since.
So I don’t know what i did, or why it stoped running. But for some reason taking the flywheel off, and putting back on was just what that engine needed.
Keep up the good work Stu,
-Kris
Ps- your website for ordering t-shirts is down today. I gotta get a couple of them. One for working in, and for on the town!😬
Hey Kris, yep, it certainly goes that way sometimes. Even though it is working it is frustrating to not know what was wrong as you don't trust that it won't happen again. Thanks for reminding me of the problem with the shirt site, all fixed up now. :)
My favorite part was " use a non impact socket so people will have something to complain and talk about " love your humor , another great video though keep em coming
Thanks Dan, glad you enjoyed the vid. :)
Yeah you know Friday is going to be a good day when you start sinking a green coopers early!
Love your videos. I hit my lower unit with mallet and broke off a small peice. My lower unit was being held up by the copper pipe stuck in the fitting.
Good video mate I've been rebuilding my 1987 yamaha 60 autolube for the past 3 weekends everything that could go wrong did snapped gearbox bolts snapped water pump bolts snapped most bolts lol but it's nearly back together and should be out on our boat next weekend but your videos have helped A lot pal.
It's always a struggle mate, but good on you for sticking with it. Enjoy your time on the water! :)
Dangar Marine I've just commented on another video Stu about the gear selector rod,
It came out of the lower unit when taking it off and I didn't realise is wasn't ment to at the time now as you know I can't get the rod back into the dog clutch to get it out of forward do you know any way to do it other than taking the lower casing to absolute bits? Thanks for any help dude
"Hammerable Screwdriver". You break me up. I think all my screw drivers have been hammered at some time. Lol
Ha! For once I actually wasn't joking! That screwdriver has a shaft that goes all the way through the handle to a metal plate at the end so it can be hammered without the handle shattering. :)
@@DangarMarine Remember not to grab it when you're grounding a coil.
That a magnet on top.
This video was great. I wish you added setting the timing on the 110. Mines a tick out I think. Small backfarts.
Remember to measure the impeller shaft so you get the right impeller. The mercury 110 9.8 has two different sizes.
Ah, interesting tip. I imagine it would be easy to get caught out with that one.
Well what a result. Great to see. My experience with Mercury outboards of that size has been they sound like guys in the factory threw in nuts and bolts before they sent them out. That actually sounds sweet . That said I'm a Yammy & Honda man myself . Thanks for posting
It did sounds rather sweet (surprisingly!) once it started running. I am more into Japanese motors too, but this one sounds like it does have a bit of life left in it.
Maybe the Mercury guys are failed Ducatti guys???? :-)
Great video Stu!! Very cool to see you work on an older Mercury. That is either a 1976, or a 1977 model...those were the only two years that Mercury used that decal scheme. I happen to have it's "little brother" a 1976 7.5 hp model. Put many enjoyable hours on Her in the 1970's on a Lake in Northern Wisconsin Here in the States, and she still looks almost new :)
Hey David, good to have an idea of its vintage now. I've noticed many people have mentioned having the 7.5, it must have been a very popular motor.
Glad to be of help on the age :) Growing up in Wisconsin in the states, I am somewhat of a vintage Mercury buff, and they used that striping for only 1976 and 1977. I had a 1977 85hp Merc (that was a Brute) with the same coloring. The little 7.5 in my opinion always seem to "punch above its weight" it seemed in power output. Back then, on identical cottage lake boats, it would out run our neighbors 9.9 Evinrude..he was not pleased :) Again Stu, thanks so much for posting this one!
Cheers for the year haha I just got one and started straight away after a clean. just needs a new impeller
have a mercury 200 with a blown piston , love your approch to taking motors apart and fixing them .
Gday mate this is the first engine i ever had as a project to work on got it to run reasonably well by the end put new parts on it ect ect and sold it for 10 dollars my loss but got some experience i think it was the earlier version old blue band motor didnt have the 110 on it , good video and smart move call it a win and give it back .
I think having one of the those projects that loses you money is a great way to learn. I would recommend anyone to find an old outboard they can experiment on if they are interested in getting their skills up.
Stu it was that squirt of " Start Ya Bastard" that done the trick....its great stuff i love it...oh the the attention of coarse.....great job mate.....Brett
I'm not so sure about the squirt as it was being used all the 100s of previous pulls too.
We used to attribute these things to cosmic rays at IBM. Great video. Thanks.
I was definitely thinking cosmic rays too. ;)
ALL 2 stroke Mercury's are hard starting. I've had two now, and sold them both, I hunt Waterfowl in Upstate NY, and the colder it gets, the harder they start. Have since switched to Evenrudes.
I like how you start off your day with a cold one. (beer) two thumbs up. and you end your day with a bike ride. way to go RIDE ON
Beer and bikes make life work living. :)
if you have a spare spanner of the slightly too small size, you can grind it lightly with a grinder and thin wheel or file, just something I have done in the past.
I know i've commented before BUT 12:44 i like how you start your morning with a beer XD
Hi Stu, you said you where going to do a merc video but was surprised you had a 110 9.8hp like my son's that I did a few videos on this past summer. cool little engine. I too was surprised being a old American outboard I had to use standard sockets and wrenches on. lucky too to get the parts online for it. The carb was weird with fuel coming out the carb choke screen bolt hole. I fixed that when I put the bolt back in with a small oring. didn't have one but put it in anyway. it stopped the leak. Anyway after that installed new lower unit seals/orings and impeller housing it worked great for them the rest of the summer. if you have time watch my 110 9.8hp videos. keep the stick on the ice mate
Hey Tim, I'll be sure to check out your vids on this motor. I wish I had known about them before!
I have a syringe (no needle) with fuel in it. Great diagnostic tool. Squirt some in the air intake intake, see what happens.
If no joy, squirt some in the spark plug holes, and give a few pulls.
Tells you quite quickly if you have a fuel, or a spark problem.
"Early Friday morning" and has a beer in hand... Love it :) we all know we work better after a few :)
Indeed we do! :)
Great video I know sometimes we just can't see any reason it will not run.
Thanks mate. It's strange, sometimes you just can't find anything actually wrong with it at all.
Dangar Marine 110 seems like a low compression number. Even if the cylinders were even
I had a 110 Merc when I was a kid but it was a bit older than this on as it still had points. The motor started great when it was cold and only required a three inch pull (100mm) to start once it was warmed up. I wish I still had that little beast as I just picked up a small skiff (tinny) last year that it would have been the perfect motor for.
Small world Stu..i just inherited one of these and searched diagnosing electronics for them and here we are..looking to add it as an auxilliary on my offshore tinny so just researching why its a no sparker..Hope the Gemmy is together and aok now.
Incredibly educational video. I learned a lot. Thanks for sharing
Great vid. You're very patient. Looks tidy for its age. Not many mechanics would bother, just tell you to throw it away.
Yes, more and more your only option is DIY with these older motors.
ALL screwdrivers are "hammerable" (7:58). Some only once though!
I forget who said, "You don't need a parachute to go skydiving. You need a parachute to go skydiving TWICE."
I enjoy your videos and sense of humour.👍I would like a quid for every time I fixed something without understanding why.😳Although you did lengthen the starting cord which would effectively warm up the combustion chamber ( albeit it that is grasping at straws) and you resolved the steaming overheating issue with the new impeller. Keep on keeping on.😀
Thanks Norman. It is true that the longer pull start cord may have made the difference.
9/16 or two halves of an inch
A 14mm wrench works great on a 9/16" nut/bolt and gives a super tight fit.
Lol at 12min 45 sec you claim “it’s now early Friday morning” And you have what looks to me a beer in your hand. Brilliant I take my hat off, I thought us Kiwis were the early drinkers. Love your vids mate very good
Had that exact motor back some 35 years ago. Spent many early mornings cursing "thunderbolt ignition" when trying to get to work.
Yes, I've heard the ignition is a bit of a problem on these motors.
Early Friday morning with a beer in hand, well played Stu. ;)
Had to get the taste of coffee out of my mouth some how! ;)
I love your vids I actually have on of those 110 mercury motors had a bad coil that "leaked" if i put rubber between the coil and the motor it would run fine but once it was properly mounted it would spark over to the motor instead of the plug sparking put new coil on now it runs good . Nice to see how it all comes apart
Ah, that's interesting to hear. I couldn't see any spark leak but it would have been interesting to spray a bit of water over it and see how quickly it started to lose spark. Thanks for the tip!
I had to start it in the dark then i could see it sparking it ran but very poorly
Realized you were new to Mercury when you were thinking "Head Gasket" & Reed valve at the top of that era motor. The round reed block is always under the carb and the pattern usually is between two cylinders.....twins have one, four cyls have two and the inline 6's have three. (Like 3 twins stacked) ALL those old mercs are "clam shell" where the entire cylinder including the combustion chamber along with the upper half of the crank case are in one casting....one of the reasons they are so rugged, but also harder to modify compression ratio for more torque, the bottom half of the crank case has the carbs......with the intake port to the reed blocks that feed two cylinders. :) Can swap out those reeds with aftermarket reeds for more RPM's if your into that type of thing.
So good video, you scared the crap outa me when you started wandering and made me wonder if all the years I have worked on Merc's I was seeing something that wasn't there....or was it? reality challenged...but by the end all was right again. :)
Interesting you call it a 'clam shell' design. When I was in the motor trade (a looooong time ago) I had to rebore a 'blind end' Bugatti six cylinder block one day. That was the same as what you call a 'clam shell'. The head, cylinder block and top half of crankcase were all one casting. Very intricate and amazingly well made.
As were Miller/Offenhausers . I build chainsaws and build "warmer" than stock saws. In that world a clam shell design as with many of the home owner saw is defined as a casting including the combustion chamber, cylinder, and upper half of the main bearing pockets as one side and the lower half of the crank case the other. The reason that's not as desirable in that paradigm is how hard changing compression is. NOT a bad thing in some applications! Typically its easy to either "deck" the base of a cylinder or remove some material from a head to play the compression game. But with a "Clam Shell" design ( Chainsaw world terminology) its very difficult to either deck the cylinder to lower it relative to the pistons or plane a head..it doesn't HAVE one! ( One of the reason I knew this guy wasn't a mercury guy ) About the only way to modify these are things like changing x-sectional area's and reed valves. Port timing...maybe. :) But your stuck with the combustion chamber geometry.....hence all added up. Clam Shell. Very rugged. Most of what I post here is for my community..:)
Yes, most motors around here are either Honda's or Yamahas, and never particularly old as they get used 365 days a year in salt water so generally get replaced by the time they are about 10 years old. It's always interesting having a poke around an unfamiliar motor though to see other ways of doing things. Thanks for the info!
1.ohh man.. you need to take apart the whole thing to take out the reed housing (if you do that ,don't worry about that you won't find sealing in that reed housing, it's designed that way)
2.don't worry about the head gasket either because the cylinders and a head is the same complete block (don't know how you called this type) only the water jacket cover what you can take off, but if not leaking...
3. 115-110psi is perfectly fine because it's a domed cross-flow design with decompressor ports
4. the screw what you are missing from the bottom of the leg is just for the plastic screen filter
5. for cold start issues -> sealings (bottom, top) ; correct carb fuel level; working choke plate
Thanks György, good to hear from someone so familiar with these motors. Yes, I'm not sure what you call that type of block either, but good to know only the water jacket cover has a gasket, one thing we can rule out. I might order than plastic screen then, debris might have been part of why the impeller got chewed up so badly. The choke plate definitely works and I wasn't the one that cleaned the carb so I might go back in and check that float level. Thanks for the information! :)
A one-piece head/block casting is usually referred to as a 'mono-block'.
Dangar Marine Do you remember Stu, when I asked you on the head gasket video, if you ever worked on a "headless" outboard? You're reply was "I can't say I have." Well, now you can say you have!! I told you if I was ever going to rebuild it, I would need to find a knowledgeable machine shop that can bore "blind cylinders". It's cool you now see one😊
Ron Volmershausen: .. also known as blind clyinders.
My merc 1987 70hp is a 3cyl, with blind cylinders. I had to ship the block halfway across the country (Canada) to a machine shop that could do the bore job. Very specialized, as very few motors use blind cylinders, and even fewer shops can bore them. It was pricey.
haaaa,good one mate!,you knocked the dust off the old Merc,she just needed some love.I have a couple old Mercs.A 1970 4hp and a 1984 4.5hp and i love them.I would sooner work on and own a Merc any day then an old JohnRude.Keep up the videos. If ya ever make it to NS Canada i will buy ya some beers because i owe you for some easy fixes on some of my other motors.
Thanks Dan, looking forward to those beers one day! :)
a few light taps with a mallet fades in wacking it like crazy.
Thanks for all your teaching and tips Chris from the snowbelt of ohio 🇺🇸
Sometimes just taking them apart and putting them back together fixes something you didn’t understand.. it happened to me with a carb once. An outboard bogging down, try to clean the carbs and they are perfectly clean. Put it all back together, it runs flawlessly.
Yes, can be a stuck float pivot or needle and seat. You never really find out what was wrong.
Ha...Land Rover electrics playing up ? Never !! Good to see Friday morning Coops to celebrate the weekend ride too mate. I have the same outboard in 7.5..probably a detuned 9.8 I'd say. Good vid Stu
No, Land Rover electrics never go wrong! ;)
For future reference you use the top but to separate the lower unit from the midsection. Just keep turning it up and it acts like a puller.
You and your channel has been a bundle of info for me! Wondering is there a required set depth on the lower end seals of an eighties 9.9 merc. I mean the ones that have to be pressed in.
Not sure on that model. Often those seals are just pressed in until they are hard up against a lip but unfortunately sometimes there is a custom tool to get the correct depth.
Awesome video! Thank you for your time and showing us!
You're welcome Rakiura. :)
Those are great motors. Great video Stu.
Thanks Will, they do seem pretty solid. :)
Love your channel hear. And love your sense of humor 🤣
Glad you enjoy it!
hey stu,all those old small merc's were hard starting bastards in my experience!..its even worse when its cold outside!i knew a guy that actually gave one away because he hated it so bad!
I'm glad it's not mine! I think I must be getting old, but I can't handle pull start motors these days until they start first pull. ;)
hometownguy71 My dad got rid of one for being so hard starting cold. He was used to his old 9.9 Johnson starting on the second pull regardless of how cold it was outside. He found him a nice 15hp Johnson and lived to be 82 but never wore it out.
Good video, those old mercs go forever.
Thanks George.
Love your videos mate always got a bottle of beer in the background man after my own heart 👍
You indeed are a plethora of information so far great video content
I have a couple of those old motors . They do have the splins for the shift linkage
Cool, thanks.
Haha it’s early Friday morning and your standing there with a beer. I’m coming to work with you 👌🏼👌🏼
It was Friday after all. ;)
Thanks for another informative vid, Stu. Love your deadpan delivery..."It's important to use a non-impact socket..." LOL. I have the same vintage Merc in 7.5hp form and they can indeed be finicky. They are famous for cooking the ancillary ignition wiring over time. Check that the insulation hasn't gone all crumbly...As for 110 the designation on the side, could be a couple of possibilities...Every once in a while Mercury Marine would make a design change to a horsepower range and rename the engines. They did that with the 40 horse motors and....voila...402 designators began to appear. Also, not sure about Down Under but in Canada and the US, any boat with 10hp and above requires license numbers to be applied for and then displayed on the hull. Manufacturers then got very coy in the seventies about producing engines in the 9.9, 9.8 hp range when they were really fully 10 hp. The 110 might be a wink to that. Anyway, very entertaining as usual. Have a great bike trip!
Not quite correct, any boat with a motor here in California has to get license numbers. But back in New York, the 10 hp was a limit on many lakes, hence the change from 10hp outboards to the 9.5, 9.8, 9.9, etc. Many folks took a 15 and put a 9.9 cover on it... :)
I'd never heard of any designation of a Mercury that eneded in other than zero, but accept that you're correct with the 402. But I don't think that was on the cowl, was it? EXCEPT the 110 engines, the numbers were 10 times the hp, so a 75 was 7.5, 1100 was 110hp, etc. It would be interested to see if the motor actually developed 11hp, vs. the "rated" 9.8, which would make the numbering correct.
RichE
Interesting about CA.... I stand corrected although here in Ontario you don't (or at least didn't) need a license under 10 hp when these things were new. We had one of the 402 Forties....could have sworn it was on the cowl....but again, that memory is forty plus years old...so many fours!!
Interesting info guys. I had always presumed that 10HP must have been a cutoff point for registration or needing a license somewhere in the world. Here it is 5HP for registration and travelling over 10 knots for a license, no matter what the boat is capable of.
Ten knots...I recall bolting that little Merc onto a wee slip of a homemade boat when I was about 15. Not much more that a 4x8 sheet of plywood. Zero freeboard, no strakes for directional control...I'd sit on the floor with my back against the transom, tiller jutting out beside my left ear....fuel tank between my legs....just screaming down the lake for all it was worth, which was surprisingly quick. Turning was interesting. Without the aforementioned strakes when you pulled the tiller to turn, the boat crabbed....and just kept going straight. Turning circle at speed was about 200 feet. Utter death trap unless it was flat calm and no traffic....and the most fun I've had on the water I can remember. :-)
I had a 1968-70 110 and it was a legend of a motor, always started no matter what abuse. Eventually crumbly wiring and decay made it a bit too chancy for use in remote locations. Newer fuels varnished the carb up readily making for cranky starts. Check the impellor regularly, a bugger to grind the old one off if it gets corroded onto the shaft.
Hi Stu, Happy Friday or probably Saturday for you by now. Good news on my Yamaha kicker motor. It would not start again a couple weeks ago after putting in the new non-ethanol fuel. Checked for spark first and as I thought the carb was plugged up again. Took it out, cleaned it and started right up today. I think after Thanksgiving I'll make a video on how to put the lower shift rod back together on this unit. It's a royal pain for access if you have ever worked on a small 4hp yamaha you'll know what I'm talking about. Tim
Great to hear it's up and running again. You're not wrong about some linkages being very tricky from an access point of view!
Cool little outboard - another interesting video
They are pretty cool little outboards. :)
I own one of these and this video was very informative. Thanks mate.
You're welcome Kevin. :)
Brilliant vid. Love the comment about giving something for people to whinge about.
Thanks mate!
when removing the lower unit....I remove that lower nut first above the propeller. the upper nut. I place a thin piece of hardwood or aluminum flat bar between the top of the nut and the surface above it. then I loosen the nut. it acts as a wedge forcing the L/U down. I never tap on the anti-cavitation plate. They are too fragile. I watched your video because I'm gathering parts to replace the corroded wires . I will install new electrical parts under the flywheel. I bought my 110 new in 1977 and after 40 years it's time I'd say ! I replaced the switchbox about 6 years ago. It still ran OK but the side of the block had something like honey on the side of it. I showed it to the president of my antique outboard motor club, a 30 year Mercury dealer. There is a goo like epoxy that seals the integrated circuit board inside the switch box. that stuff melts out. Another guy at the outboard meet looked at my switch box melted too. he worked at Mercury 42 years and told he was head of quality control when Mercury machined 9800 Merc 110 engine blocks in ONE batch process ! Anyway he said it was an epoxy to seal the electronics. Before I got the new switchbox we tried putting a 4 HP Mercury GNAT switchbox on it. It is said it is the best electronic switch box Mercury ever made. The 110 started on the first pull. I put the engine in gear and started to drive the boat away but it only went to a fast idle speed. when I twisted the throttle wide open the engine never sped up. Back at the dock I had it in neutral and would it up wide open and slow it down and it would go - ran-nan-nan-nan-nan just like a dirt bike. It had a real crisp sound. Well the Merc dealer ordered me a new switchbox and we put it on and it runs perfectly. it always take 3 pulls to start. I only use no ethanol gasoline at 89 octane and usually I double up the oil and run 25:1 because that what I use in my Mark 10, Mark 28, and Merc 250 - all of them are automatic transmission outboards 1957-1962. I tried some 100LL aviation gas but I didn't like it. It turned my spark plugs white and I looked at the piston crowns and they were spotlessly clean in a 1958 outboard. I'm a little scared of that stuff because it has some lead in it
Great vid Stu.
I was however looking forward to you finding the exact cause.
Were you able to bring back the fault? Could the high voltage have been spilling somewhere? Cracked spark leads? Bad caps?
I think I read once that cranking in dark conditions may reveal something like that.
I am thinking that you may have moved something (maybe just slightly) that made the cause dissappear. Intermittent faults can be annoying.
I was hoping to find the cause too. Taking the pull start off does mean bending the wires for the coils so maybe that is where the fault lies. If you have high voltage leaks you can normally hear it arcing as well, but yes, running in the dark and spraying water on the leads can certainly help find the problem.
Ok. I haven’t tried nor heard of the water spray method, but I know it will help transfer the high voltage to something like my hands if probing for current or simply not being carefull enough :-)
On another note - I just got to think of the proces caused by broken screws/bolts and having to drill them out and rethreading, maybe even installing an insert. It must have happened to you a few times as well. Just wondering if you have some preferred methods in the whole proces of being gentle with existing threads. Also on choice of inserts types/brands and choice of material for the insert. Maybe you find it interesting enough for a video.
I have found a few things that work for me but I am very happy to harvest on other peoples experience.
For me when screw has snapped)
(the real # 1 - don’t rush!)
#1 - always carefully hammer center point and start of with 3 mm drill bit.
# 2 - drill out with cobolt drill bits - they are hard.
# 3 - only drill to a depth of max. 8-10 mm to avoid a stuck drillbit then change to a drill bit 0.5 mm larger. Repeat until at the needed hole size then repeat the proces.
No one wants a stuck and possibly broken drill bit.
# 4 - If trying to salvage existing aluminum threads with a little leftover stainless steel inside the hole, I will be eager to vacuum out every 1-2 turns when tapping the threads (meaning a total removal of tap every time) plus everytime I feel it could remove some SS.
On inserts I have only used the non-removable coil type from Helicoil (stainless). They seem to do the job. I am not sure if there is a better choice?
humleridder my 9.8 supposedly “just needed a new exhaust gasket” when purchased. Come to find the exhaust plate was cracked, and 4 bolts were snapped off. I was able to remove one by welding a nut on the end of it and backing it out. One other one came out with an easy out from the 80s, very old bits. The last two were drilled and tapped, but did not work. I took it to a buddy who used time serts which are a million times better than helicoil and will withstand the time. Some new gaskets, a new plate and she was back up in no time.
A W E S O M E it saw Stu coming 💪🏻
Your comment to tro"lls and great skills / good humor / pleasant beeing made another subb. First day I saw your films
Thanks mate, glad you enjoy the channel! :)
Love it. I was waiting for the 'ahah!' moment for the fault...
I was waiting for that too, I'll let you know if something ever shows up!
Early fri morning drinkng a beer this is my guy I subscribed
These motors were and are still very common in my area of the Northeast USA. They must have been the perfect combination of price and power for rowboats for decades. They also last forever, but the impeller is hard enough to fix that lots of them end up in some outbuilding or shed in deep storage. Great Video!
Interesting that so many of them were sold. It's a shame that they end up out of action because a simple impeller though.
Love all of the experts
You can't have enough experts!
Very informative. Great to watch and learn.
Thanks Gary. :)
Love the video mate! And appreciate the diagnosing steps really helpful
Thanks mate, glad you liked it. :)
"its important to use a non-impact socket so people have something to criticize and comment about" awesome!
Stu, I have had reed/rotary valves 'glue' to the base because of old/dried out two stroke oil sitting on them. The clean up was a cup of diesel to flush things out - a suggestion by a mates father- and we ended up with three RD250s to ride for a few weeks. Loved the 9/16ths of 2 halves an inch - where did you learn that one? Sounds like an Arn-ism- and I haven't heard that line for 40 years!Hope the ride went well.
Hey Ron, good tip about checking for the reeds being stuck down. They are often inspected for their ability to close and seal but not so much for their ability to open. That measurement is just one I made up, it's always how imperial measurements sound to me, way more complicated than they need to be!
My grandfather used to mumble about imperial measurements all the time and had a comment very similar to yours. But his favourite was always 'four fifths of bugger all'.
My pull cord keeps comming out can you do a video on how to replace the pull cord on one of these so I can see what I'm doing wrong. Thanks
Curious? Ive seen other outboards started by means of a portable drill. Can a 110 be started in this manner? It would just be a fun video. All 110 fans would be greatful.
I'm sure it would be possible with a big enough drill. Unfortunately I don't have a 110 to film at the moment.
Just bought a 1982 9.8 today. After cleaning out the mud wasp nest in the electrical generation area under the flywheel, she started right up and idled for a few seconds on Starting fluid. Can't do anymore until the linkage that connects to the carb arrives. Only part besides the cover in front of the carb butterfly missing. I appreciate you showing me where the reeds are. Was wondering. Thanks.
Very high quality video. Thank you
Glad you liked it!
Another great video Stu. Checked all your vids but unable to find out whether or not water from tell tale should warm up when flushing motor after 4 or so minutes. Plenty of water pissing out of tell tale. Maybe a cooling system troubleshooting quick vid with this and some other points for us amateurs? Cheers mate!
Thanks mate. This video will show you want is going on with the tell tale ruclips.net/user/edit?o=U&video_id=joEQChcZl2A Often on outboards the tell tale water doesn't actually go through the engine water jackets but it will still get warm from the whole block conducting heat into the exhaust cover.
Phew i was getting worried about the beer scenario until 12:44 then everything was ok again. Still waiting for those Dangar Marine stubby holders ;-)
Ah yes, I must work on those!
Love your humour, mate. "Early Friday morning" ... with a beer in your hand :-) That's awesome.
That wasn't a joke! ;)
Even better, then ;-)
Who knew reed valves would be in the crankcase id still be scratching my head lol
"alright its friday morning"
>Has a stubbie in his hand.
Hahaha love it, good channel mate great source of info! Keep it up cobba
Thanks, will do!