Holding the throttle open and pulling it over must clear the excess gas out. It works on my old sled, in fact that’s what the owners manual says to do. Like you said now I know exactly how to start it so it’s never an issue but if your stuck out on the trail it’s a life saver. Nice video Dave 👍🏻
Hi David. Love the show. One you missed here that is a mystery to many....if a fuel pump has a pinhole in the diaphragm, gas will run down the impulse line. Happens a lot in the old Mach 1, Mach z, Formula...etc. Happy Sledding! Len
03 rmk 800. Bogged down and died under heavy throttle, idled poorly afterwards until things settled into place after. Solution - drained fuel mostly, added half a tube of Lucas injector/carb cleaner, which is like 2x recommended concentrate on a full tank, ran it dry, the added 5 gallons, and poured in the other half. I hate taking apart carbs, so I just hit them with enough cleaner to kill it, just about
Great info Dave! The older vintage sleds were quite a pain because of fouling plugs from improper starting (excessive primer) and because of richer oil mixtures. Todays sleds are much easier to start but I like your take on why they flood. A good trick I learned from an older gentleman is, when you're in a flooded situation pull your plugs and pull it over (like you showed) and before putting the plugs back in, give each plug a shot of starting fluid, that will dry up the wet plug and make it more prone to fire. It's worked for me many times.
Hi Dave , New to sledding and running into the flooding problem. This just started with my sled. I'm running a 500 bored 30 over and this is a rotax engine i have installed in a 93 Polaris Indy. i synced the carbs and adjusted the air fuel mixture to the best of my knowledge. This thing hauls ass. I have maybe 60 miles on the new engine but now at start up its flooding its self out. once I do get it running and warmed up runs great. After watching your video that is the first thing I'm going to check. Thanks for the info.
If you think that thing is hard to pull over try a mach 1 670! The mxz 670 for that year were extremely easy to pull over due to the great big recoil. The mach1, had the smaller recoils from a lot of smaller motor ski doos. Also, I would rather just hold it wide open and pull the thing then blow gas all over my sled. You did a good job explaining how fuel mixtures can be rich or lean, I think pretty much anyone would understand it with how you said it
LOL @ "Extremely easy to pull over" ...Not sure if you noticed the big '97 MXZ 670 in some of my videos, but in case you didn't, well...I have one....and they're not. :)
Honestly I love the primer bulb over the choke lever I always found it more reliable but they are easy too flood. I've also flooded it but when it gets flooded I hold throttle wide open to get it to start. Now I have a fuel injected machine. I never found the 670cc engine hard to pull over one handed but to each their own. Happy trails
I really enjoy the comedic inserts and bloopers. Just pulled my carbs out thinking they may have sucked up something a mouse may have left behind to find a backfire blew out both my slides. Hmm no wonder it wouldn't start lol
I'm new to sledding this year and I come across all the odd stuff. One cylinder one lean turned out to be a needle and seat. A new gas line sucking in air. and now I'm fighting it bogging in till wot kicks in. I did rebuild the carb synced the carbs put it to factory specs and all that. I'm sure its fun once you get the hang of the carb stuff. Your video made me thing I should start the checklist over again though. Thank you.
If it’s super flooded you can always use a butane torch down the cylinders, just make sure to turn the fuel off and pull it over quickly if it catches fire lol. Has saved me tons of time on an old 80s Yamaha rather than pulling with plugs out, especially if the crankcase is full of fuel. Also, glad to see you’re making more videos these last few months, was missing your vids for awhile there!
Oh my. I really appreciate you watching and commenting, but I can’t express how much I don’t recommend doing that. (How would you use a butane torch down the cylinders without pulling plugs anyway) There are so many reasons that’s a bad idea, fire risk damage to your engine… please just don’t
@@MyOldSled haha fair, I expected a reply like that. Grandpa showed me this trick back in the mid 90s. Yes pull the plugs, then using a little Coleman gas tank and nozzle, quickly pass it down the cylinder. May give a bang like a .22 rifle, may smoke, may catch fire for a sec. In any case pull cord. Gets rid of gas fast, have had some sleds where I’ve pulled for an hour with plugs out and fuel off, but due to fuel in the crank it wouldn’t start. The torch was the only way. Plus, if you get stuck on a lake in -20, it’s a helluva lot quicker than waiting for it to dry naturally. Maybe a bit risky I guess but been doing it for years and never had a problem. Torch is nice to have on trails for drying plugs too
lol glad I didn’t disappoint. I don’t like to disagree with comments but I believe in responding when people take the time to comment. But I also have to reply honestly and I believe that is a terrible approach. All due respect to grandpa! Glad you haven’t damaged anything or hurt yourself..yet. Seriously I appreciate you commenting anyway. (Kids, don’t listen :)
Just bought a 97 MXZ 583, started great. Spent 3 or 4 days working on it replacing just about every idler bearing as they were seized or close too. One pull and away we went off to the gas station. Filled up and couldn't start it again. Flooded! The carb needle wasn't closing and I'm guessing with the tank full, the added pressure allowed fuel to flow way too easily. Cleaned and rebuilt carbs and immediately saw fuel coming out the overflow on the pto side. Took the carb out and cleaned it all out and rebuilt again. This time it held but still couldn't get it started and noticed fuel coming out the air hole on the top of the pump. I'm new to snowmobiles and was told fuel pump diaphragm must be bad now that the carb is building pressure in the gas line. Installed new pump. After 3 pulls I could see fuel coming out of the new pump in the same spot. Everyone was stumped other than to say my new pump must be bad. I ripped apart the old pump to find the diaphragm was fine and that there was no way fuel went through it. The crank case was full of fuel and was back feeding into the top of the pump :( Disconnected pulse line to fuel pump, pulled it over till no more fuel came out, put it all back together and it started first pull! Yay! Lol after a week I now a lot more about how it all works, your video is a little late, but definitely would have been helpful too. Keep up the posts!
Yes that hole,is a vent to allow the diaphragm to move. The pulse line pumps fuel because of the alternating differential pressure in the crank case. I haven’t pulled mine apart, but There are check valves that allow the fuel to flow through it one way, so you may have corrected the problem with the new pump, but had to clear the crank case of fuel?
@@MyOldSled , there's no check valve, the pulse line connects to the port at the top of the diaphragm which as you said drives the pump. The problem was just how much fuel got into the crank case from the faulty carb allowing fuel to flow into the cylinder. The fuel was pushing from the crank case onto the top of the diagram. If anyone ever asks about fuel spitting out of the hole in the centre of the fuel pump, that's why.
Sorry. Understand re pulse line. Some fuel pumps have a flapper valve on the inlet and outlet for the fuel pump.Doesn’t matter, I understand what you mean. Glad you worked it out
David another great episode love your you tube show great information love it keep up . Watch every episode never miss any of them . Always look forward to it cheer's.
I have a carborator sled 2005 mxz ski-doo 380 fan cooled . And a Polaris 2016 indy fuel infected liquid cool . Had a problem getting the ski-doo to run right last year its was bogging when you would put it into Reverse no power . It wouldn't idle very well when stopped it would slowly quit after sitting there after 30 second or more . Finally took it in to a repair center to get it setup right . This year was idling to high over 25 hundred to 3 grand so I backed it off a little. Marked the idle screws with a marker just to make sure they were even across and not offset idle screw were the same on both . And for my information when setting them .
on my 17 cat i have a problem with a rich mixture/hesitation/bog/plug foul when i pin it and it hasnt had a chance to warm up for high rpm overfueling problems exhaust valves are often the culprit. learning to rebuild a carb is one of the first things worth doing when you buy a new sled and it get you farmiliar with that new sled and its components!
I'm not sure about 2 strokes but i know 4 strokes will usually make more power and run better between 11.5 to 13:1. At full throttle. 14.7:1 is usually just at a cruising rpm which you'll only get with EFI since you can't tune for fuel economy and power/throttle response on a carburetor. Very informative video David!
There really isn’t a perfect ratio as it’s effected by several factors. The ideal ratio that provides maximum fuel efficiency at all speeds and conditions, the normally accepted ideal average is 14.7 to 1. Too much to get into in a video about flooding.
Hi Guillaume, curious where you got this info, 11.5 to 1 would be 8% or over the flammability point for gasoline. Are u talking about compression maybe?
@@MyOldSled i'm still speaking about air/fuel ratio. There is alot of factors for a/f ratio like you said. It is still not desirable to run an engine that lean under heavy load. And most engine will not make peak power at 14.7:1 and are usually on the edge of being to lean and most engine will have poor throttle response and have dangerously high exhaust gas temperatures which can melt pistons. And like i said in my last comment. 14.7:1 is a target a/f ratio for fuel economy and light load like driving on the highway at a steady pace. 11.5:1 is to rich for cruising around but some engines can make more power and last longer if the target a/f ratio is a little bit richer.
Got it. Interesting discussion. Thanks for sharing. Like I said 14-1 is textbook “ideal average , across all speeds and conditions, not accounting for incomplete combustion etc. Too much to dig into for this video. 11.5 still seems way rich but I’m certainly not an expert in tuning. To explain rich/lean I think 14.7 to 1 is still a good ratio to use. Keep commenting, or msg on my Facebook page any time!
Hi, I just got this one rev that sat for awhile and I was trying to get it running good today. Cleaned the carbs, fuel pump, new sparks. it bogs down when you give it throttle and tries to die but it idles perfect. Sounds like one piston isn’t working well or something when it’s going. Going to check those floaters tomorrow, if not that what could it be? Did a lot of troubleshooting today but can’t seem to figure it out
2002 summit 800 all new gaskets n rings. Cleaned carbs boots are soft and tight. Fuel mixture screws are set to 1 and 1/2 turns. Fuel lines are clean plugs are mint. It idles just fine but doesnt wanna run or accelerate without half choke. Ideas?
I dont think 1.5 is your air setting. Check it with your dealer but i think thats too lean. Everyone assumes thats where they should be but it varies. Don’t take my word for it though - check. Your machine is running lean if you need choke. Other reasons are dirty fuel lines, blocked filters…
Hey David awesome video it was right on the money as far as what's going on with my 94 Grand Touring might I mentioned it only has 1400 miles anyways it's exactly what's going on with my sled it's a 580 XTC severe flooding runs great and then what started as soon as i shut it off starts putting gas all over the barn floor and since that started I can't get it restarted due to the flooding I obviously now the after washing your video I'm thinking the floats must be stuck or something as to maybe that's causing the gas to pour out of the bottom pan anyways Hopefully this wasn't too confusing but I'm trying to explain the best I can other than that it's a great running sled I use it on my trap line and but now I'm having this problem and like I said it's floodi ng so bad I can't get it restarted and that's even after pulling the plugs and clearing the cylinders
Enjoy your videos. Bought an old Touring SLE 500. You have given lots of good advice. Have you done a video on how to store the machine at the end of season? If not might be a good one?
01 mxz 700 new top end ,bottom 4k . first 3 heat cycles were fine, sat a few weeks and started again, all hell broke lose. Rough idle, no acceleration just bogs down but maintains idle. Dumping gas for sure. Carbs were rebuilt..I'm thinking fuel pump or a recheck on the float needles. Air screw set at 1.5 .. Any ideas, very frustrating.
I have a1996 ski-doo formula sls. I have to open the left or belt side slider screw 3 turns out to get it to idle. 6000k starts first pull cyl psi 120 both. The other carb is at 1.5 out. What do you think 🤔
Hey Dave I had an issue with my 1996 mxz583 and it was my float bowls were actually cracked so the floats would never move up to shut the flow of fuel. Took me a while to figure it out but once I did the sled ran like new after.
Thank you for posting these videos Dave; they are awesome and really appreciated. I am a bit of a novice mechanically, so I'd really appreciate some advice. I have a single cylinder 2008 RF300 Tundra Ski-doo and bought it second hand back in 2012. It's given me problems ever since and I'm beginning to think it's a lemon. Basically, it is incredibly difficult to start (pull start only) and I am never confident that I'll be able to start it. At the end of 2022 winter, I decided to drain the gas tank entirely. I did this with a pump, then ran the carburetor dry. This season, it won't start. I've just spent the last 3 days trying to start it and it won't start. I pulled the plug (after 100's of pulls) and it's bone dry, so clearly, it's not flooding. Can you offer any advice. Thanks in advance, Dave (with a sore arm in the Okanagan).
Hmmm.. well, I'm no expert... I'm just stubborn and I like to figure things out. Have you pulled the drain screw to see if fuel is getting to the carb? If not...then just check from the tank forward...theres a filter in the tank...sometimes I think that can end up above the fuel level, or get plugged...does that sled have a fuel shutoff? If fuel is getting to the end of the line going to the carb, but the bowl is dry, then it would be the needle stuck in the closed position. There is a pulse line from the crank case to the fuel pump that provides pressure. If the fuel pump is bad it's a simple rebuild, it's basically just a diaphragm inside. Or...is it getting fuel, but has no spark? Message me on Facebook and we can chat about it.
My sled a ski doo formula mach 1 xtc Ran great then started to bog down and a while after that stopped working on the left cylinder. Now I have done a compression test and the result was excellent on both. (Exactly the same 10 to 1) Disassembled the rave system (both of them) cleaned and found the O-rings ok (not brittle) Assembled everything and started it up (started straight away) but still no change. Checked spark plugs and if there's a spark on both of them (it is) Can't wrap my head around the problem. It might be sensible to mention the high fuel consumption (very high) A couple of people have said that it could be the reed valve in conjunction with the fuel pump (if the membrane in the pump are damaged in any way) Do you have any idea what the problem can be?
Would it be beneficial to tie the primer pump to the carb fuel inlet instead of the throat? Then prime until the seat seals and you get the resistance in the pump and the fuel system is then charged for startup/ like a boat primer bulb essentially.
Hi Mikey. I would say no, because that isn’t really what the primer is for. It enriches the mixture by introducing fuel into the airstream. The bulb on your outboard is there to draw fuel a fair distance to get it to the carburetor, which generally has a choke. (Unless if is fuel injected) Thanks for taking the time to comment!
The tip about watching the fuel line while priming helps. Lately it seems like I have to press the throttle to help it along. Is that wrong? Or should I just pump the primer more? Our temps have been up to -28 at night. I have the '97 Grand Touring with 583 rotax, electric start. I'm worried I might run my battery down. Once it starts, I'm good for the rest of the day.
I did watch your video about how to start a 2 stroke when cold but I have those few additional questions. I saw that you were giving it gas and then had to prime a couple more times, too. I just don't know if holding the primer up is helping or hurting. It seems like it helps.
I have found that with most Skidoo models feeling for 2 full primer squirts and leaving the primer up helps. Re-hitting the primer when it starts I have also found helps. And not touching the primer for the rest of the day, unless you stop for a very long period of time. I have also in the past set the parking brake and inserted a quarter in the thumb throttle to prop it open. Happy riding!
My 86 indy when not in use i have to shut the gas off or it floods .. picked up carb kits and when it get nice will rebuild .. but im thinking needle and seat
I have a 97 mxz 670 and it starts fine cold but when you shut it off when its warmed up it does not lie to start back up unless you hold the throttle slightly open to let air in, the sled runs perfectly otherwise this is just a rather annoying thing to deal with
@@MyOldSled air screw is set 1/4 turn in on both carbs from stock adjustments just did a complete rebuild of the motor and re did the carbs, everything is at factory specs
I have a 2006 gsx 550f, when I am at higher speeds and start to really get up on the rpms. The sled feels like its getting to much fuel or not enough. It then starts to die and I theb have to let off the throttle so it won't die.
Well my Skidoo flood so much it pours gas out of the exhaust. Clean the carburetors more times than I can count and it continues to flood and does not want to start. Everything inside the carburetor is new. Now discouraged to the point where I don't even want to own a Ski-Doo anymore new or old.
I feel for you that kind of think is frustrating but if the fuel pump is ok, then its needle and seat or o-ring, float sticking or float arm bent up too much.
The air/fuel screw. If I am running rich and want to lean it out, do I screw in it further? Or screw it out further than the 1-1/2 turns that is standard? Sorry if I missed it.
Counter clockwise increases air. Remember this is just at idle. Also, running too rich is a pain, running too lean melts pistons so I would find out the right settings. Also check the spark plugs and monitor for lean condition.
Hi love the video i got a problem with my sled it starts and then it dies and then when i pull out the spark plugs they r wet and i hand it up to that i could reve it up but it just wont idle and the piston compression is just little bit over 90 psi and i cant figures it of but i think that it could be the compression on it but not sure and it is fuel injection on a plairas rmk 900.
Thats right you did say that sorry. There are a couple of sensor issues that can cause a lean condition, but so will low compression as the charge in the cylinder wont burn properly. Really hard to diagnose without seeing it.
Yeah I took the head off and I could wigal the piston so Yeah and it was losing compression when I hand a compression tester on it I could see it going down so I think I got it figured out. Thanks
Not sure if you will see this but let my neighbors borrow my 96 Polaris xlt600 triple and they broke the choke cable. If I disconnect the cables completely will this help because I think it is the reason why my sled is so flooded, might just buy new carbs too and choke cable but for the time being will this work?
@@MyOldSled just really old carbs already rebuilt them twice and the choke lever broke new one is coming but was wondering if it's okay to just disconnect them from now
Try it. Its an enrichment valve that enriches mixture by decreasing airflow through the pilot. I think theres a spring that holds it open but i cant recall. I don’t have a choke.
My sled it’s a Polaris Star 250, it’s my sons .. It won’t start it smells like gas and I see gas coming out of the exshust , I cleaned the carbs looks great but still same issue.. any help I hope you answer Before the snow is gone 😭
If you pull pulse line off pump and fuel comes out of the pump, the diaphragm is leaking fuel into crank case….or its a worn or dirty needle and seat. Maybe get a rebuild kit and replace the seals etc.?
Hey Dave , I just put new plugs in my 2006 Gtx. It’s fuel injected. The sled fired up nice today 2nd push to be honest. On my b bday jan.28 I went to get some wood on the trail. The sled bogged and would not reach full speed even when I opened her up. I changed the plugs the sled fired up like I mentioned above. The wife an I went for a rip today, I park it. Went back out to fire it up again and it’s just back to foul plugs again. Feb 3 What’s your opinion on the issue?
Well, hard to diagnose via email, but…assuming you have the right plugs, and when you say bog down, the tether is connected properly, your oil pump might be sticking. If your tether is dirty or not connected, it will run on one cylinder…then the plugs get fouled…
@@MyOldSled when I say bog, I mean like the engine will almost turn off an pick back up again. I have the right plugs yes. What’s a tether? Could you please explain that. Thank you so much for the info. I’m gonna get new plugs tomorrow try again.
just bought a 98 formula z 670 in great shape for the year only has 3300 miles my problem is that when i take it out for a ride it will go good for a bit then boggg out and idle high at like 4 grand once i pull over and sit there for a min or two it will go down to regular idle at about 1.5 grand to1.8 ive drained the gas tank put new fuel filter cause it dont have shut off valve fresh gas and cleaned carbs twice its not leaking gas out of over flow lines but you can smell it for sure just took it for a 170 mile ride two weeks ago thats when the problem started im assuming its needle and seats just looking for some help any input would be appreciated
@@MyOldSled we checked that yesterday while cleaning carbs for the second time they where dirty for sure i took it for a ride and it didn't happen until 10 miles in and instead of it happing just on bottom end it happened on top end like 70 mph i was thinking maybe needle and seats its most defiantly getting to much fuel for sure was thinking maybe the Orings are bad did sit for three years
Thanks, its a 98 skandic 500. I've only had the sled for a couple years and haven't cleaned the carb. I was told that since it runs so well once started, which it does, the carbs don't need cleaning. I did get it started last night, 10 pulls with less choke. I ran it for about an hour to get it good and warm.After it cooled I pulled the plugs. They were nice and dry and the cardboard colour. The plugs were new.
Does anybody have any ideas about my skidoo 2005 550f I got it started and it ran good for a couple days but one day I shut it off of and it would not start(there was a loose spark plug)after I did start it it was boggy and it kept dieing now it won’t start at all. My only thought could be stuck float(carbs were cleaned ten months ago) My pride won’t let me bring it to a shop, any ideas?
We’ll the fuel pump and carbs are the entire equation so assuming you used the correct parts, and have the right mixture settings for your sled, that leaves over choking/priming. Oh is the air box clean. Restricted airflow will cause a rich condition
@@MyOldSled I don’t have an air box on my sled and yes we did use the right parts for the carbs and fuel pump we literally fixed everything that causes flooding and it still floods
Rotax type 343 with Mikuni impossible to fix, 340 engine .all new gasket & seal, 145 PSI compression on both cylinder .vacuum test done, I took a good working Mikuni VM30-91 from a running engine & installed it on this engine & it flooding at idle .tried another carburetor from another good 340 engine & keeps flooding I am clueless...What do I do wrong?
You pulled it off the same engine? It didn’t flood in that one? Are you running it with the air-box on? If the air box is blocked it would run rich and flood.
And this happened to me?? The primer was defective?? There are one way valves in the primer and if they get screwed up or leak??,,fuel can syphon into the carbs and cause problems..? If this happens,,pinch the tube supplying the carb!
@MyOldSled I ended up figuring it out, I think the o ring on the float needle was bad and the fuel would just keep flowing past it, thanks for the reply good sir
There a lot I didn’t say. This video is about why snowmobiles flood, not carb tuning. Only so much I can fit in one video. I’ll be doing more carb videos,
Holding the throttle open and pulling it over must clear the excess gas out. It works on my old sled, in fact that’s what the owners manual says to do. Like you said now I know exactly how to start it so it’s never an issue but if your stuck out on the trail it’s a life saver. Nice video Dave 👍🏻
Too much work :) thanks for watching
You totally sound like my old high school small engines teacher. He was a great teacher. Good job
Thank you Jace. Glad you enjoyed it. All the best for the new year.
Hi David. Love the show. One you missed here that is a mystery to many....if a fuel pump has a pinhole in the diaphragm, gas will run down the impulse line. Happens a lot in the old Mach 1, Mach z, Formula...etc. Happy Sledding! Len
Hi Len thanks. Yeah I realized that would be good to include, right after I posted :)
Excellent explanation
03 rmk 800.
Bogged down and died under heavy throttle, idled poorly afterwards until things settled into place after.
Solution - drained fuel mostly, added half a tube of Lucas injector/carb cleaner, which is like 2x recommended concentrate on a full tank, ran it dry, the added 5 gallons, and poured in the other half.
I hate taking apart carbs, so I just hit them with enough cleaner to kill it, just about
Great info Dave! The older vintage sleds were quite a pain because of fouling plugs from improper starting (excessive primer) and because of richer oil mixtures. Todays sleds are much easier to start but I like your take on why they flood. A good trick I learned from an older gentleman is, when you're in a flooded situation pull your plugs and pull it over (like you showed) and before putting the plugs back in, give each plug a shot of starting fluid, that will dry up the wet plug and make it more prone to fire. It's worked for me many times.
Thanks SK.
Hi Dave , New to sledding and running into the flooding problem. This just started with my sled. I'm running a 500 bored 30 over and this is a rotax engine i have installed in a 93 Polaris Indy. i synced the carbs and adjusted the air fuel mixture to the best of my knowledge. This thing hauls ass. I have maybe 60 miles on the new engine but now at start up its flooding its self out. once I do get it running and warmed up runs great. After watching your video that is the first thing I'm going to check. Thanks for the info.
Yeah when your talking Frankensleds I don’t even know what to suggest. Good luck, thanks for watching
If you think that thing is hard to pull over try a mach 1 670! The mxz 670 for that year were extremely easy to pull over due to the great big recoil. The mach1, had the smaller recoils from a lot of smaller motor ski doos.
Also, I would rather just hold it wide open and pull the thing then blow gas all over my sled.
You did a good job explaining how fuel mixtures can be rich or lean, I think pretty much anyone would understand it with how you said it
LOL @ "Extremely easy to pull over" ...Not sure if you noticed the big '97 MXZ 670 in some of my videos, but in case you didn't, well...I have one....and they're not. :)
Oh… also a huge difference when it’s cold. Warmed up it’s easy
lol
Honestly I love the primer bulb over the choke lever I always found it more reliable but they are easy too flood. I've also flooded it but when it gets flooded I hold throttle wide open to get it to start. Now I have a fuel injected machine. I never found the 670cc engine hard to pull over one handed but to each their own. Happy trails
Once its warm, and running right it’s easy. When its cold and flooded, you wont pull it over easy with your left hand.
@@MyOldSled cold is a different story if it's cold flooded I pull the plugs clear the cylinders and dry plugs
😆
I really enjoy the comedic inserts and bloopers. Just pulled my carbs out thinking they may have sucked up something a mouse may have left behind to find a backfire blew out both my slides. Hmm no wonder it wouldn't start lol
That’ll do it
I'm new to sledding this year and I come across all the odd stuff. One cylinder one lean turned out to be a needle and seat. A new gas line sucking in air. and now I'm fighting it bogging in till wot kicks in. I did rebuild the carb synced the carbs put it to factory specs and all that. I'm sure its fun once you get the hang of the carb stuff. Your video made me thing I should start the checklist over again though. Thank you.
I would order a carb kit and then you know you have all stock jets o-rings and gaskets
@@MyOldSled Thats the rebuild I mentioned I did. Jest, seals, needles ect and ultrasonic cleaned the carb. Maybe some dirt got in there again?
What sled is it again, sorry?
@@MyOldSled its a 96 polaris 440
Msg me via facebook if you want to bat some ideas around.
If it’s super flooded you can always use a butane torch down the cylinders, just make sure to turn the fuel off and pull it over quickly if it catches fire lol. Has saved me tons of time on an old 80s Yamaha rather than pulling with plugs out, especially if the crankcase is full of fuel. Also, glad to see you’re making more videos these last few months, was missing your vids for awhile there!
Oh my. I really appreciate you watching and commenting, but I can’t express how much I don’t recommend doing that. (How would you use a butane torch down the cylinders without pulling plugs anyway) There are so many reasons that’s a bad idea, fire risk damage to your engine… please just don’t
@@MyOldSled haha fair, I expected a reply like that. Grandpa showed me this trick back in the mid 90s. Yes pull the plugs, then using a little Coleman gas tank and nozzle, quickly pass it down the cylinder. May give a bang like a .22 rifle, may smoke, may catch fire for a sec. In any case pull cord. Gets rid of gas fast, have had some sleds where I’ve pulled for an hour with plugs out and fuel off, but due to fuel in the crank it wouldn’t start. The torch was the only way. Plus, if you get stuck on a lake in -20, it’s a helluva lot quicker than waiting for it to dry naturally. Maybe a bit risky I guess but been doing it for years and never had a problem. Torch is nice to have on trails for drying plugs too
lol glad I didn’t disappoint. I don’t like to disagree with comments but I believe in responding when people take the time to comment. But I also have to reply honestly and I believe that is a terrible approach. All due respect to grandpa! Glad you haven’t damaged anything or hurt yourself..yet. Seriously I appreciate you commenting anyway. (Kids, don’t listen :)
I think if my crank case was that full of gas, id pull the pulse line and pull it over a few times as opposed to building a pipe bomb. ;)
Flooded a 96 mxz 440 my son had. Pulled hard enough to begin with, dam near gave a heart attack trying to start it flooded. Thx for the info.
Yep a lot of sleds are hard to pull over. So I use that method, but again be careful. Thanks for watching.
Just bought a 97 MXZ 583, started great. Spent 3 or 4 days working on it replacing just about every idler bearing as they were seized or close too. One pull and away we went off to the gas station. Filled up and couldn't start it again.
Flooded! The carb needle wasn't closing and I'm guessing with the tank full, the added pressure allowed fuel to flow way too easily. Cleaned and rebuilt carbs and immediately saw fuel coming out the overflow on the pto side. Took the carb out and cleaned it all out and rebuilt again. This time it held but still couldn't get it started and noticed fuel coming out the air hole on the top of the pump. I'm new to snowmobiles and was told fuel pump diaphragm must be bad now that the carb is building pressure in the gas line. Installed new pump. After 3 pulls I could see fuel coming out of the new pump in the same spot. Everyone was stumped other than to say my new pump must be bad. I ripped apart the old pump to find the diaphragm was fine and that there was no way fuel went through it. The crank case was full of fuel and was back feeding into the top of the pump :( Disconnected pulse line to fuel pump, pulled it over till no more fuel came out, put it all back together and it started first pull! Yay! Lol after a week I now a lot more about how it all works, your video is a little late, but definitely would have been helpful too. Keep up the posts!
Yes that hole,is a vent to allow the diaphragm to move. The pulse line pumps fuel because of the alternating differential pressure in the crank case. I haven’t pulled mine apart, but There are check valves that allow the fuel to flow through it one way, so you may have corrected the problem with the new pump, but had to clear the crank case of fuel?
@@MyOldSled , there's no check valve, the pulse line connects to the port at the top of the diaphragm which as you said drives the pump. The problem was just how much fuel got into the crank case from the faulty carb allowing fuel to flow into the cylinder. The fuel was pushing from the crank case onto the top of the diagram. If anyone ever asks about fuel spitting out of the hole in the centre of the fuel pump, that's why.
Sorry. Understand re pulse line. Some fuel pumps have a flapper valve on the inlet and outlet for the fuel pump.Doesn’t matter, I understand what you mean. Glad you worked it out
Ignore me, that wouldn’t make a difference anyway it’s on the other side of the diaphragm
Ryan, I appreciated your comment about knowing a lot more after you figured it out. Great way to learn.
David another great episode love your you tube show great information love it keep up . Watch every episode never miss any of them . Always look forward to it cheer's.
Thanks so much Scott. Glad you enjoy them.
I have a carborator sled 2005 mxz ski-doo 380 fan cooled . And a Polaris 2016 indy fuel infected liquid cool . Had a problem getting the ski-doo to run right last year its was bogging when you would put it into Reverse no power . It wouldn't idle very well when stopped it would slowly quit after sitting there after 30 second or more . Finally took it in to a repair center to get it setup right . This year was idling to high over 25 hundred to 3 grand so I backed it off a little. Marked the idle screws with a marker just to make sure they were even across and not offset idle screw were the same on both . And for my information when setting them .
Reverse is common when its not running right. So are you ok now?
on my 17 cat i have a problem with a rich mixture/hesitation/bog/plug foul when i pin it and it hasnt had a chance to warm up for high rpm overfueling problems exhaust valves are often the culprit. learning to rebuild a carb is one of the first things worth doing when you buy a new sled and it get you farmiliar with that new sled and its components!
Exhaust valve problems will have an effect on fuel consumption, but it won’t effect the mixture. Never pin it without letting it warm up.
I'm not sure about 2 strokes but i know 4 strokes will usually make more power and run better between 11.5 to 13:1. At full throttle. 14.7:1 is usually just at a cruising rpm which you'll only get with EFI since you can't tune for fuel economy and power/throttle response on a carburetor. Very informative video David!
There really isn’t a perfect ratio as it’s effected by several factors. The ideal ratio that provides maximum fuel efficiency at all speeds and conditions, the normally accepted ideal average is 14.7 to 1. Too much to get into in a video about flooding.
Hi Guillaume, curious where you got this info, 11.5 to 1 would be 8% or over the flammability point for gasoline. Are u talking about compression maybe?
@@MyOldSled i'm still speaking about air/fuel ratio. There is alot of factors for a/f ratio like you said. It is still not desirable to run an engine that lean under heavy load. And most engine will not make peak power at 14.7:1 and are usually on the edge of being to lean and most engine will have poor throttle response and have dangerously high exhaust gas temperatures which can melt pistons. And like i said in my last comment. 14.7:1 is a target a/f ratio for fuel economy and light load like driving on the highway at a steady pace. 11.5:1 is to rich for cruising around but some engines can make more power and last longer if the target a/f ratio is a little bit richer.
Got it. Interesting discussion. Thanks for sharing. Like I said 14-1 is textbook “ideal average , across all speeds and conditions, not accounting for incomplete combustion etc. Too much to dig into for this video. 11.5 still seems way rich but I’m certainly not an expert in tuning. To explain rich/lean I think 14.7 to 1 is still a good ratio to use. Keep commenting, or msg on my Facebook page any time!
Great video once again. Thank you for the info.
Thanks for watching Duane.
Hi, I just got this one rev that sat for awhile and I was trying to get it running good today. Cleaned the carbs, fuel pump, new sparks. it bogs down when you give it throttle and tries to die but it idles perfect. Sounds like one piston isn’t working well or something when it’s going. Going to check those floaters tomorrow, if not that what could it be? Did a lot of troubleshooting today but can’t seem to figure it out
2002 summit 800 all new gaskets n rings. Cleaned carbs boots are soft and tight. Fuel mixture screws are set to 1 and 1/2 turns. Fuel lines are clean plugs are mint. It idles just fine but doesnt wanna run or accelerate without half choke. Ideas?
I dont think 1.5 is your air setting. Check it with your dealer but i think thats too lean. Everyone assumes thats where they should be but it varies. Don’t take my word for it though - check. Your machine is running lean if you need choke. Other reasons are dirty fuel lines, blocked filters…
When he’s talking about the atv having and says it doesn’t have a real choke. He is correct. It is acually an enrichment device
Enrichment valve, correct.
Hey David awesome video it was right on the money as far as what's going on with my 94 Grand Touring might I mentioned it only has 1400 miles anyways it's exactly what's going on with my sled it's a 580 XTC severe flooding runs great and then what started as soon as i shut it off starts putting gas all over the barn floor and since that started I can't get it restarted due to the flooding I obviously now the after washing your video I'm thinking the floats must be stuck or something as to maybe that's causing the gas to pour out of the bottom pan anyways Hopefully this wasn't too confusing but I'm trying to explain the best I can other than that it's a great running sled I use it on my trap line and but now I'm having this problem and like I said it's floodi ng so bad I can't get it restarted and that's even after pulling the plugs and clearing the cylinders
Good luck! Hope you get it figured out.
Enjoy your videos. Bought an old Touring SLE 500. You have given lots of good advice.
Have you done a video on how to store the machine at the end of season? If not might be a good one?
Absolutely. Great suggestion.
01 mxz 700 new top end ,bottom 4k . first 3 heat cycles were fine, sat a few weeks and started again, all hell broke lose. Rough idle, no acceleration just bogs down but maintains idle. Dumping gas for sure. Carbs were rebuilt..I'm thinking fuel pump or a recheck on the float needles. Air screw set at 1.5 .. Any ideas, very frustrating.
I had that same exact problem on my 99 Polaris 500 Indy and I replaced the carb floats, problem solved 👍🏻🇺🇸
Thanks for watching Shane. Glad you solved it.
Thank you I’m new to snowmobiling and I have found your channel to be very informative and helpful so thank man happy sledding 👍🏻
I have a1996 ski-doo formula sls. I have to open the left or belt side slider screw 3 turns out to get it to idle. 6000k starts first pull cyl psi 120 both. The other carb is at 1.5 out. What do you think 🤔
I’ll look later and see if I can find it but I think it’s 1.75 each side.
Hey Dave I had an issue with my 1996 mxz583 and it was my float bowls were actually cracked so the floats would never move up to shut the flow of fuel. Took me a while to figure it out but once I did the sled ran like new after.
Thank you for posting these videos Dave; they are awesome and really appreciated. I am a bit of a novice mechanically, so I'd really appreciate some advice. I have a single cylinder 2008 RF300 Tundra Ski-doo and bought it second hand back in 2012. It's given me problems ever since and I'm beginning to think it's a lemon. Basically, it is incredibly difficult to start (pull start only) and I am never confident that I'll be able to start it. At the end of 2022 winter, I decided to drain the gas tank entirely. I did this with a pump, then ran the carburetor dry. This season, it won't start. I've just spent the last 3 days trying to start it and it won't start. I pulled the plug (after 100's of pulls) and it's bone dry, so clearly, it's not flooding. Can you offer any advice. Thanks in advance,
Dave (with a sore arm in the Okanagan).
Hmmm.. well, I'm no expert... I'm just stubborn and I like to figure things out. Have you pulled the drain screw to see if fuel is getting to the carb? If not...then just check from the tank forward...theres a filter in the tank...sometimes I think that can end up above the fuel level, or get plugged...does that sled have a fuel shutoff? If fuel is getting to the end of the line going to the carb, but the bowl is dry, then it would be the needle stuck in the closed position. There is a pulse line from the crank case to the fuel pump that provides pressure. If the fuel pump is bad it's a simple rebuild, it's basically just a diaphragm inside. Or...is it getting fuel, but has no spark? Message me on Facebook and we can chat about it.
When I drive my skidoo 500 sometimes it bogs down and then comes back up to rpm’s but now I have a fixed
I’d start with a good carb cleaning, try and get the specs for your air screw. Put good plugs in it. Start from there.
My sled a ski doo formula mach 1 xtc
Ran great then started to bog down and a while after that stopped working on the left cylinder.
Now I have done a compression test and the result was excellent on both. (Exactly the same 10 to 1)
Disassembled the rave system (both of them) cleaned and found the O-rings ok (not brittle)
Assembled everything and started it up (started straight away) but still no change.
Checked spark plugs and if there's a spark on both of them (it is)
Can't wrap my head around the problem.
It might be sensible to mention the high fuel consumption (very high)
A couple of people have said that it could be the reed valve in conjunction with the fuel pump (if the membrane in the pump are damaged in any way)
Do you have any idea what the problem can be?
Have you cleaned carbs and made sure they are set to spec?
@@MyOldSled not yet, will do that
Would it be beneficial to tie the primer pump to the carb fuel inlet instead of the throat? Then prime until the seat seals and you get the resistance in the pump and the fuel system is then charged for startup/ like a boat primer bulb essentially.
Hi Mikey. I would say no, because that isn’t really what the primer is for. It enriches the mixture by introducing fuel into the airstream. The bulb on your outboard is there to draw fuel a fair distance to get it to the carburetor, which generally has a choke. (Unless if is fuel injected) Thanks for taking the time to comment!
The tip about watching the fuel line while priming helps. Lately it seems like I have to press the throttle to help it along. Is that wrong? Or should I just pump the primer more? Our temps have been up to -28 at night. I have the '97 Grand Touring with 583 rotax, electric start. I'm worried I might run my battery down. Once it starts, I'm good for the rest of the day.
I did watch your video about how to start a 2 stroke when cold but I have those few additional questions. I saw that you were giving it gas and then had to prime a couple more times, too. I just don't know if holding the primer up is helping or hurting. It seems like it helps.
I generally keep them primer out and give it another shot or two when it hesitates until it warms up enough that it doesnt need a richer mixture
I have found that with most Skidoo models feeling for 2 full primer squirts and leaving the primer up helps. Re-hitting the primer when it starts I have also found helps. And not touching the primer for the rest of the day, unless you stop for a very long period of time. I have also in the past set the parking brake and inserted a quarter in the thumb throttle to prop it open. Happy riding!
My 86 indy when not in use i have to shut the gas off or it floods .. picked up carb kits and when it get nice will rebuild .. but im thinking needle and seat
Sounds right
I have a 97 mxz 670 and it starts fine cold but when you shut it off when its warmed up it does not lie to start back up unless you hold the throttle slightly open to let air in, the sled runs perfectly otherwise this is just a rather annoying thing to deal with
Could slightly adjust idle up a bit, or if it’s a little rich it would be richer when it warmed up. Do you know where the air screw is set?
@@MyOldSled air screw is set 1/4 turn in on both carbs from stock adjustments just did a complete rebuild of the motor and re did the carbs, everything is at factory specs
I have a 2006 gsx 550f, when I am at higher speeds and start to really get up on the rpms. The sled feels like its getting to much fuel or not enough. It then starts to die and I theb have to let off the throttle so it won't die.
Clean carbs, check boots for splits.
Well my Skidoo flood so much it pours gas out of the exhaust. Clean the carburetors more times than I can count and it continues to flood and does not want to start. Everything inside the carburetor is new. Now discouraged to the point where I don't even want to own a Ski-Doo anymore new or old.
Diaphram in the fuel pump maybe, gas flowing through the pulse line to the crank case?
@@MyOldSled nope diaphragm in fuel pump gas lines are all brand new. There's no reason for it not to start and run besides to Ski-Doo being cursed.
No, if it was that my two wouldn’t start. To clarify, what did you replace inside the carbs?
@@MyOldSled everything including floats that cost $58 for one
I feel for you that kind of think is frustrating but if the fuel pump is ok, then its needle and seat or o-ring, float sticking or float arm bent up too much.
The air/fuel screw. If I am running rich and want to lean it out, do I screw in it further? Or screw it out further than the 1-1/2 turns that is standard? Sorry if I missed it.
Counter clockwise increases air. Remember this is just at idle. Also, running too rich is a pain, running too lean melts pistons so I would find out the right settings. Also check the spark plugs and monitor for lean condition.
@@MyOldSled Good deal, thanks. I changed my needle position and that seemed to make a big difference.
Thank you
Hi love the video i got a problem with my sled it starts and then it dies and then when i pull out the spark plugs they r wet and i hand it up to that i could reve it up but it just wont idle and the piston compression is just little bit over 90 psi and i cant figures it of but i think that it could be the compression on it but not sure and it is fuel injection on a plairas rmk 900.
Have you cleaned the carbs? Compression is on the low side as well.
Yeah thats what I thought to and it is fuel injection
Thats right you did say that sorry. There are a couple of sensor issues that can cause a lean condition, but so will low compression as the charge in the cylinder wont burn properly. Really hard to diagnose without seeing it.
Yeah I took the head off and I could wigal the piston so Yeah and it was losing compression when I hand a compression tester on it I could see it going down so I think I got it figured out. Thanks
Not sure if you will see this but let my neighbors borrow my 96 Polaris xlt600 triple and they broke the choke cable. If I disconnect the cables completely will this help because I think it is the reason why my sled is so flooded, might just buy new carbs too and choke cable but for the time being will this work?
Why would you buy new carbs? Did the cable break or the choke lever? It’s plastic and prone to break. They sell a kit for like $25 Easy fix.
@@MyOldSled just really old carbs already rebuilt them twice and the choke lever broke new one is coming but was wondering if it's okay to just disconnect them from now
Try it. Its an enrichment valve that enriches mixture by decreasing airflow through the pilot. I think theres a spring that holds it open but i cant recall. I don’t have a choke.
My sled it’s a Polaris Star 250, it’s my sons ..
It won’t start it smells like gas and I see gas coming out of the exshust , I cleaned the carbs looks great but still same issue.. any help I hope you answer Before the snow is gone 😭
If you pull pulse line off pump and fuel comes out of the pump, the diaphragm is leaking fuel into crank case….or its a worn or dirty needle and seat. Maybe get a rebuild kit and replace the seals etc.?
Hey Dave ,
I just put new plugs in my 2006 Gtx.
It’s fuel injected.
The sled fired up nice today 2nd push to be honest.
On my b bday jan.28 I went to get some wood on the trail.
The sled bogged and would not reach full speed even when I opened her up.
I changed the plugs the sled fired up like I mentioned above.
The wife an I went for a rip today, I park it. Went back out to fire it up again and it’s just back to foul plugs again. Feb 3
What’s your opinion on the issue?
Well, hard to diagnose via email, but…assuming you have the right plugs, and when you say bog down, the tether is connected properly, your oil pump might be sticking. If your tether is dirty or not connected, it will run on one cylinder…then the plugs get fouled…
@@MyOldSled when I say bog, I mean like the engine will almost turn off an pick back up again. I have the right plugs yes. What’s a tether? Could you please explain that.
Thank you so much for the info.
I’m gonna get new plugs tomorrow try again.
You can wipe the plugs clean while you figure it out. The tether is the springy safety cord that clips onto the sled
What spark plugs are you running?
just bought a 98 formula z 670 in great shape for the year only has 3300 miles my problem is that when i take it out for a ride it will go good for a bit then boggg out and idle high at like 4 grand once i pull over and sit there for a min or two it will go down to regular idle at about 1.5 grand to1.8 ive drained the gas tank put new fuel filter cause it dont have shut off valve fresh gas and cleaned carbs twice its not leaking gas out of over flow lines but you can smell it for sure just took it for a 170 mile ride two weeks ago thats when the problem started im assuming its needle and seats just looking for some help any input would be appreciated
Slides sticking?
@@MyOldSled we checked that yesterday while cleaning carbs for the second time they where dirty for sure i took it for a ride and it didn't happen until 10 miles in and instead of it happing just on bottom end it happened on top end like 70 mph i was thinking maybe needle and seats its most defiantly getting to much fuel for sure was thinking maybe the Orings are bad did sit for three years
If it sat for three years I’d probably get a carb rebuild kit.
@@MyOldSled im on it will let you know what it was just as soon as i fix thanks for the in put happy riding
@@robertbrisk5112 Good luck Robert!
My sled floods without priming and when cold with full choke, it has a 2 stage choke. Too much choke? Even when cold?
I guess it depends how cold. Try it with less choke. What sled? When did you clean carbs last?
Thanks, its a 98 skandic 500. I've only had the sled for a couple years and haven't cleaned the carb. I was told that since it runs so well once started, which it does, the carbs don't need cleaning. I did get it started last night, 10 pulls with less choke. I ran it for about an hour to get it good and warm.After it cooled I pulled the plugs. They were nice and dry and the cardboard colour. The plugs were new.
Thanks
Does anybody have any ideas about my skidoo 2005 550f
I got it started and it ran good for a couple days but one day I shut it off of and it would not start(there was a loose spark plug)after I did start it it was boggy and it kept dieing now it won’t start at all. My only thought could be stuck float(carbs were cleaned ten months ago) My pride won’t let me bring it to a shop, any ideas?
What do the spark plugs look like?
I just had just put fresh ones in and got it started the first time
And after it won’t start what do they look like.
If you like, message me on my facebook page we can chat.
I have a few thoughts, easier to chat. facebook.com/MyOldSled
My sled keeps flooding we cleaned the carbs changed the gaskets and we even put in new carbs and we changed the fuel pump to it keeps flooding
We’ll the fuel pump and carbs are the entire equation so assuming you used the correct parts, and have the right mixture settings for your sled, that leaves over choking/priming. Oh is the air box clean. Restricted airflow will cause a rich condition
@@MyOldSled I don’t have an air box on my sled and yes we did use the right parts for the carbs and fuel pump we literally fixed everything that causes flooding and it still floods
Rotax type 343 with Mikuni impossible to fix, 340 engine .all new gasket & seal, 145 PSI compression on both cylinder .vacuum test done, I took a good working Mikuni VM30-91 from a running engine & installed it on this engine & it flooding at idle .tried another carburetor from another good 340 engine & keeps flooding I am clueless...What do I do wrong?
You pulled it off the same engine? It didn’t flood in that one? Are you running it with the air-box on? If the air box is blocked it would run rich and flood.
Thats an odd one if you tried two carbs from the same engine, and the weren’t flooding on those engines, id say air-box or fuel pump?
No air box, Yes I replaced the fuel pump, same result ,flooding at idle @@MyOldSled.I even cancel the primer in case ,same result flooding at idle
@@MyOldSled Problem solved, intake gaskets leaks
Thats very strange. That should make it run lean
My 91 super jag is really touchy, the carb floods so easily it probably could be considered an antitheft device.
That’s probably what they had in mind ;)
My sled fooled it self after I turned it off and the crankcase is full of gas it won't start it's a old 98 summit 670
If it’s fooling itself, might be needle and seat.
I have another video Idea 4 stroke vs 2 stroke
Thanks Carson. Thats a good one.
My sleds rich because of all the money ive dumped into it!
lol. Maybe it’ll lend you enough for a new sled
And this happened to me?? The primer was defective?? There are one way valves in the primer and if they get screwed up or leak??,,fuel can syphon into the carbs and cause problems..? If this happens,,pinch the tube supplying the carb!
My sled has a fuel shut off. Normally if the primer leaks it won’t pull gas up properly and you know its time to replace it.
Where did you go?????
Three weeks of covid and then I recently my brother. :( I will be back
My sled seems to flood itself after its running and I ride for 2 minutes
What have you done to problem solve so far
@MyOldSled I ended up figuring it out, I think the o ring on the float needle was bad and the fuel would just keep flowing past it, thanks for the reply good sir
My carb is clean
Glad to hear it. Mine isn't.
You didnt tell us How put them back on and set them up even
There a lot I didn’t say. This video is about why snowmobiles flood, not carb tuning. Only so much I can fit in one video. I’ll be doing more carb videos,
Keeps flooding one clyinder and lose of power than it does.
What kind of sled and what have you tried so far?
…and whats the compression