Hi Kaleb, I saw your commetn 2 days ago and I started to reply but then stopped because I felt it deserved a proper response and I have been crazy busy over the last couple days. I do have some suggestions. First of all, if you have a 93 GTX, I would recommend taking the entire thing apart and learning all the systems. These skis are great because - with the exception of a few little aspect of the MPEM system - these skis are incredibly simple. They were designed well and are easy to repair. You can have the entire ski apart in a matter of hours, not difficult at all, fuel system, drive train, etc etc. Take it all apart and learn what every single part does and how it functions, that way you can be sure that when you put it all back together, you'll be confident on the water that you wont have a breakdown, no suprises. The fuel system is a big concern if you have an old ski. Take the fuel tank out and clean it, make sure that there is no debris in the tank and you will probably find a small magnet in there that is from the sending unit which is supposed to be glued to your fuel float and it always falls off, which is why no vintage sea-doo fuel gauges work ! Stick that magnet back on and youll have a working fuel guage ! There are just all kinds of silly little issues with the fuel system that will prevent it from running properly. Take everything apart, clean it, replace the parts that are old and crusty, like fuel lines etc etc. If you have the original grey fuel lines that came with this sea-doo, get rid of those, they rot out and can clog up your carb. replace all the lines, take the carbs apart (video on my channel) clean the carbs and potantially replace any parts that may be worn out, take the tank out and inspect the sending unit to make sure the little magnet is there. I will make a video today about the fuel system for Sea-Doo for you so you can know how the entire thing works, best of luck with your rebuild.
So Scotty here is my dilemma. I have taken this ski out and the fuel system performed well. All new fuel lines and the carburetors have been rebuilt. After the last trip out the engine stalled and would not restart. Low compression on the Mag side cylinder. This is why I reached out, clearly the ski is in need of a complete rebuild.
@@kalebpaterson1747 Ah I see. Have you verified that you have good spark on both plugs ? Engine stalling can be due to problems with your MPEM and other electrical components, and they do tend to be problematic on the vintage skis. I have 2 skies in my shop right now with fried MPEM's, but other than that they are mechanically sound. I will be making more videos on this very soon. How low is your compression on the mag side cylinder ?
So just recently i blew up my 95 seadoo, one of the piston skirts went kaboom, and i cleaned out all the material i ended replacing the rotary valve and the plate because they were a little dented qnd scatched up as long as a brand new rebuild kit on the top end, when i went to start it it started right up no issues smoked like youde think it would after a rebuild and not to mention it was boggy ass heck, and eventually it just started to bog down and die and would have alot of trouble starting again, and when i was dowj at the rotary valve the plate didnt go on right because that gear was out a bit far so i ended uo hittinf it in farther, is there any chance that missing that c clip is my issue?
@@matthewbraun-l4t your issue is likely bad crankcase seals. My guess is that they were likely damaged with the original incident. The symptoms you are describing are born from the fact that as soon as the machine is in the water under load, the crankshaft flexes a bit and then crankcase start bogging, suckin air and sometimes water if there is water in the hull. It will also burn a tonne of oil in that scenario too
@@UOttawaScotty I had messed up the timing somehow while rebuilding it, I'm gonna take it out on the water tomorrow and fully set in the rebuild I already had it warmup a few times
@@UOttawaScotty well I took it out just a bit ago, and at first it wasn't going up in rpms in the water and backfiring a bit when I left off the gas, but eventually it kicked itself out of it and sounded almost like a 4 stroke and then eventually it kicked into some higher rpms and before I knew it the machine started bogging down and then it started clicking metal sounds and locked up
Gonna take a look at it tomorrow and see what happens, and when I hit the start button sometimes it clicks and sometimes it'll spin something I'm not sure what but it doesn't spin it fast and it'll grind a bit
@@gregschille1388 yes, shavings will get into the crankcase. I have known guys to just leave all that in there without retriving it, and had no issues...but I would try and get as much of that out as humanly possible !
Hey Scotty, I have a 1996 SeaDoo SPI and I was riding it today and all of the sudden there was a high pitched noise and I lost all power. I tried to crank it immediately and it turned over just fine. I got it home and when I turn it over there is a loud grinding noise. I think my brass rotary valve drive gear is stripped. Would that make sense? Compression is ~150 both cylinders. I will be pulling off the rotary valve cover tomorrow to inspect but does that sound plausible and if so do you have a link to get one from Amazon? Thank You.. And to add, as soon as I heard the high pitch screech and lost power the motor turned over just fine but it will not start anymore and when I got it home it will not run but turns over like always but has a loud grinding noise coming from lower center of the engine.
Yes, this sounds like a rotary valve gear problem to me. Your engine will turn over just fine, but because the rotary valve is not turning anymore, it is impossible for the engine to start. The question is why the rotary valve gear failed, that will have to be determined, perhaps the bearing on the gear failed.
Let me know when you determine if it was the rotary valve gear or not, I will interested to know. BTW, you will have to make a tool to get the rotary valve gear out. You can get it out by using an end piece of PVC piping with a small threaded bolt to pull it out.
@@UOttawaScotty I can tell you my theory on why I think it may have failed. I bought this ski off of Facebook. The ad said great shape 96 SPI for sale. Will not stay running because of no fuel delivery. So, I went up and looked at it. The ski is in excellent condition. Looks almost new. New wear ring. Fresh top end rebuild. I have all the receipts. When he was showing it to me he said I don't know where this hose goes. Me working on computerized fuel injection automotive, small engines as well for over 30 years I was not worried. So I bought it for 1000 dollars, nice trailer too! One thing he did tell me was that he had removed the oil injection and he even gave me the SBT oil injection pump block off kit. I got home and realized the hose was the "pulse line'. There was also a one way check valve in the line, huh? Lol. I removed that too and fuel problem solved. I didn't ride it though because i wanted to put on the oil injection pump block off kit. While I was in there I noticed the 2 large lines going into the center of the block and found out they lubed the rotary valve gear. I called him and asked if he had the oil tank and I went and picked it up. I had to press him to see if he had run the ski with those lines empty and he said he didn't think so. Well I think he did because when I bought it he had a primer bulb in the fuel system and said it would run fine on the lake as long as he pumped the primer bulb. So that is why I think the rotary valve gear failed. Sorry so long. Thanks so much for your response!
@@UOttawaScotty i feel like mine ran into a similar issue. Either the rotary valve or needle bearings feell out of the rod. It was running fine and all of the sudden lost power and heard like a springy rattling noise almost like rings failed but compression is still very strong in my spin by hand tests. I paddled back to shore so didnt want to risk damaging anything further. it was acting on water like it lost all fuel, it was also running very rough like struggling before it turned off completely. Im glad at least it spins by hand before I tear apart the head and start checking for failed rings or bearings
@@1234mikelopez4321 I saw it on another vid. He threaded a bolt into the end of it, with a washer and a 1 inch tubular spacer. Then just tightened up the bolt. In some cases, simply threading the bolt in, giving you something to pull on, will be enough to pull it out by hand.
@@UOttawaScotty thank you elso most time when brass gear goes bad is brass residue in the oil i already try get most i can , but is impossible get all with out taking motor all apart ,is that ok if install new one like that
Do you have a video on the removal of the shaft?
Thank you. This helps.
when u convert to premix you need to loop these lines together or keep them hooked to the bottle to make sure this brass gear gets oil
The lines under the rotary??
Hey Scotty, I am in a very similar place with my 93 GtX 657. Just wondering if you have any suggestions for restoring/rebuilding these skis.
Hi Kaleb, I saw your commetn 2 days ago and I started to reply but then stopped because I felt it deserved a proper response and I have been crazy busy over the last couple days. I do have some suggestions. First of all, if you have a 93 GTX, I would recommend taking the entire thing apart and learning all the systems. These skis are great because - with the exception of a few little aspect of the MPEM system - these skis are incredibly simple. They were designed well and are easy to repair. You can have the entire ski apart in a matter of hours, not difficult at all, fuel system, drive train, etc etc. Take it all apart and learn what every single part does and how it functions, that way you can be sure that when you put it all back together, you'll be confident on the water that you wont have a breakdown, no suprises. The fuel system is a big concern if you have an old ski. Take the fuel tank out and clean it, make sure that there is no debris in the tank and you will probably find a small magnet in there that is from the sending unit which is supposed to be glued to your fuel float and it always falls off, which is why no vintage sea-doo fuel gauges work ! Stick that magnet back on and youll have a working fuel guage ! There are just all kinds of silly little issues with the fuel system that will prevent it from running properly. Take everything apart, clean it, replace the parts that are old and crusty, like fuel lines etc etc. If you have the original grey fuel lines that came with this sea-doo, get rid of those, they rot out and can clog up your carb. replace all the lines, take the carbs apart (video on my channel) clean the carbs and potantially replace any parts that may be worn out, take the tank out and inspect the sending unit to make sure the little magnet is there. I will make a video today about the fuel system for Sea-Doo for you so you can know how the entire thing works, best of luck with your rebuild.
So Scotty here is my dilemma. I have taken this ski out and the fuel system performed well. All new fuel lines and the carburetors have been rebuilt. After the last trip out the engine stalled and would not restart. Low compression on the Mag side cylinder. This is why I reached out, clearly the ski is in need of a complete rebuild.
@@kalebpaterson1747 Ah I see. Have you verified that you have good spark on both plugs ? Engine stalling can be due to problems with your MPEM and other electrical components, and they do tend to be problematic on the vintage skis. I have 2 skies in my shop right now with fried MPEM's, but other than that they are mechanically sound. I will be making more videos on this very soon. How low is your compression on the mag side cylinder ?
The compression on my mag side is down at 105 and on the PTO side it’s at 125. There is spark at both plugs
Sir I have a problem about this rotary valve shaft her in the Philippines , sir my question is if there is an timing of this rotary valve,
@@PragadosRaymondjohn-m3b yes, you need to time the rotary gear properly with a rotary wheel timing gauge, not hard, pretty straight forward.
So just recently i blew up my 95 seadoo, one of the piston skirts went kaboom, and i cleaned out all the material i ended replacing the rotary valve and the plate because they were a little dented qnd scatched up as long as a brand new rebuild kit on the top end, when i went to start it it started right up no issues smoked like youde think it would after a rebuild and not to mention it was boggy ass heck, and eventually it just started to bog down and die and would have alot of trouble starting again, and when i was dowj at the rotary valve the plate didnt go on right because that gear was out a bit far so i ended uo hittinf it in farther, is there any chance that missing that c clip is my issue?
@@matthewbraun-l4t your issue is likely bad crankcase seals. My guess is that they were likely damaged with the original incident. The symptoms you are describing are born from the fact that as soon as the machine is in the water under load, the crankshaft flexes a bit and then crankcase start bogging, suckin air and sometimes water if there is water in the hull. It will also burn a tonne of oil in that scenario too
@@UOttawaScotty I had messed up the timing somehow while rebuilding it, I'm gonna take it out on the water tomorrow and fully set in the rebuild I already had it warmup a few times
@@matthewbraun-l4t let me know how she runs tomorrow, Ill be interested to hear
@@UOttawaScotty well I took it out just a bit ago, and at first it wasn't going up in rpms in the water and backfiring a bit when I left off the gas, but eventually it kicked itself out of it and sounded almost like a 4 stroke and then eventually it kicked into some higher rpms and before I knew it the machine started bogging down and then it started clicking metal sounds and locked up
Gonna take a look at it tomorrow and see what happens, and when I hit the start button sometimes it clicks and sometimes it'll spin something I'm not sure what but it doesn't spin it fast and it'll grind a bit
hi, is there a video on removing the shaft
If the rotary gear shears off will it send shavings all inside motor and contaminate the oil in the motor
@@gregschille1388 yes, shavings will get into the crankcase. I have known guys to just leave all that in there without retriving it, and had no issues...but I would try and get as much of that out as humanly possible !
@@UOttawaScotty thanks
@@UOttawaScottyin which part of the crankcase? Just where the rotary valve is or in the combustion chambers?
Hey Scotty, I have a 1996 SeaDoo SPI and I was riding it today and all of the sudden there was a high pitched noise and I lost all power. I tried to crank it immediately and it turned over just fine. I got it home and when I turn it over there is a loud grinding noise. I think my brass rotary valve drive gear is stripped. Would that make sense? Compression is ~150 both cylinders. I will be pulling off the rotary valve cover tomorrow to inspect but does that sound plausible and if so do you have a link to get one from Amazon? Thank You.. And to add, as soon as I heard the high pitch screech and lost power the motor turned over just fine but it will not start anymore and when I got it home it will not run but turns over like always but has a loud grinding noise coming from lower center of the engine.
Yes, this sounds like a rotary valve gear problem to me. Your engine will turn over just fine, but because the rotary valve is not turning anymore, it is impossible for the engine to start. The question is why the rotary valve gear failed, that will have to be determined, perhaps the bearing on the gear failed.
Let me know when you determine if it was the rotary valve gear or not, I will interested to know. BTW, you will have to make a tool to get the rotary valve gear out. You can get it out by using an end piece of PVC piping with a small threaded bolt to pull it out.
@@UOttawaScotty I can tell you my theory on why I think it may have failed. I bought this ski off of Facebook. The ad said great shape 96 SPI for sale. Will not stay running because of no fuel delivery. So, I went up and looked at it. The ski is in excellent condition. Looks almost new. New wear ring. Fresh top end rebuild. I have all the receipts. When he was showing it to me he said I don't know where this hose goes. Me working on computerized fuel injection automotive, small engines as well for over 30 years I was not worried. So I bought it for 1000 dollars, nice trailer too! One thing he did tell me was that he had removed the oil injection and he even gave me the SBT oil injection pump block off kit.
I got home and realized the hose was the "pulse line'. There was also a one way check valve in the line, huh? Lol. I removed that too and fuel problem solved. I didn't ride it though because i wanted to put on the oil injection pump block off kit. While I was in there I noticed the 2 large lines going into the center of the block and found out they lubed the rotary valve gear.
I called him and asked if he had the oil tank and I went and picked it up. I had to press him to see if he had run the ski with those lines empty and he said he didn't think so. Well I think he did because when I bought it he had a primer bulb in the fuel system and said it would run fine on the lake as long as he pumped the primer bulb. So that is why I think the rotary valve gear failed. Sorry so long. Thanks so much for your response!
@@UOttawaScotty I sure will and thanks about the tip about making a removal tool!
@@UOttawaScotty i feel like mine ran into a similar issue. Either the rotary valve or needle bearings feell out of the rod. It was running fine and all of the sudden lost power and heard like a springy rattling noise almost like rings failed but compression is still very strong in my spin by hand tests. I paddled back to shore so didnt want to risk damaging anything further.
it was acting on water like it lost all fuel, it was also running very rough like struggling before it turned off completely.
Im glad at least it spins by hand before I tear apart the head and start checking for failed rings or bearings
how does the rotaary valve oil move?
There is an oil pump attached to the valve body
@@UOttawaScotty I have a problem where the oil get mixed with water in the rotary valve oil tank
How can I resolve this?
Well you never did do a video on that. So tell me, how did you pop that shaft out of there??
For real!!
@@1234mikelopez4321 I saw it on another vid. He threaded a bolt into the end of it, with a washer and a 1 inch tubular spacer. Then just tightened up the bolt. In some cases, simply threading the bolt in, giving you something to pull on, will be enough to pull it out by hand.
@@thediplomasta5891 Need to remove the C clip first
can i replaced it without taking motor a part ?
You have to take the rotary valve off, no way around that. I have seen this repair done while the engine is still in the hull but its very difficult.
@@UOttawaScotty thank you elso most time when brass gear goes bad is brass residue in the oil i already try get most i can , but is impossible get all with out taking motor all apart ,is that ok if install new one like that