Tracker Seadoo Jet Jon Build

[brianb2247]

if the key is sheared it will throw off the timing to run rough or not at all

 

[Ranchero50]

Ditto. Mine washed out the keyway slot and took some ingenuity to repair. I used a cut off wheel the cut a straight key way slot. The shaft is tapered so it looks funny in the second pic but lasted until I got the rebuilt one.

 

[bdeemo]

I cheated. I replaced spark plug wires, tried cutting bridges off of a couple of new spark plugs, tested spark some more, and I can't help but think it's the carburetors. The engine is turning over great so I don't think it's the key. I went out last night and drove an hour to buy another 1995 seadoo xp. I was able to pick one up running great for $900 so I can swap parts and troubleshoot. Reason being I have a fishing tournament I want to make it to next weekend and I'm cutting it real close. First thing I'll swap over is carbs, next thing is cdi box if that doesn't work. Finally I'll swap over engine if that doesn't work, and then I'll repair my engine when I have time and try to sell the jetski in running condition.

Ah it sucks to have to cheat but I didn't have time! I'll work on it tomorrow morning before work, and after work.

 

[bdeemo]

Boy oh boy is this thing being a PITA!!!

First off, I bought another donor ski, which didn't seem to run well. Then I pulled the carbs on that and cleaned the jets and it ran good.

When I pulled the carbs off of the ski, I noticed that there is NO oil in the crank. Odd, I thought, because my boat had a ton of oil spewing out of the carb holes under the cylinders. Turns out that it was a bunch of leftover oil from when I broke the seized engine free before my top end. I filled the cylinders with marvel mystery oil, which I later realized was ******** as it probably just needed a little of the oil. Someone on one of these forums suggested that to another guy and I did it. I thought I had blown all of that out, but when I realized this donor ski didn't have any I knew it wasn't supposed to be there.

To get the oil out I put a vaccuum on the PTO carb hole with the carbs out, and plugged the other hole with a rag. I turned over the engine with the spark plugs in. Then I poured gas down the spark plug holes and repeated process about 5 times. Then I put spark plug boots on, and burnt the excess gas up while still vacuuming. Surprisingly it started like running off of the gas in the cylinders, and I thought, oh wow, fixed!

Anyhow I got it all out, and then I put the GOOD carbs from the donor ski on the boat, and still can't get it to run. I'm getting fuel but it barely wants to fire. I'm not sure where to go from here, it's really weird that it was running with the vacuum on the one side.

Not gonna make that fishing tournament with my boat so I'm helping get my brothers boat ready for it.

 

[Ranchero50]

What's the whole story on the engine? Your thread is jumping around a lot and (honestly) is confusing me.

Engine was stuck or? Oil running out? Flushing gas through a 2 stroke? Did you check and make sure the intake wheel was timed correctly and had the correct clearances?

 

[amk]

When my key sheered it would turn over just fine too. Did you try spraying starter fluid in it if it won't start with that then something is wrong internally and not a carb issue

 

[bdeemo]

Sorry I realize I'm jumpy. Heres the history of the motor in chronological order(in a nut shell)
Bought a used 95 seadoo xp for $250 in July last year
Took it to the lake, and it ran GREAT, probably over 50mph
Work ensued, and I let the engine sit until like April of this year

Got all the electrical and fuel lines hooked up, and it started up after a bunch of starter fluid, but seemed to be running flawlessly. Didn't have enough power to get on plane, which I suspect was impeller pitch and boat weight.
Took it around for a little while(2 mins) trying to adjust weight to get it on plane, and it died. I figured it died because it was lugging around and carbs got clogged, but it wouldn't turn over. Then I took plugs out, STILL wouldn't turn over. I don't know whether there was cylinder buildup or it got overheated, but the engine was slightly seized.

Took it home, FILLED cylinders with marvel mystery oil(Mistake, should have just used a little) and broke it loose with the starter and plugs out.

I then blew out all of the oil(or so I thought from the cylinders, and still couldnt get it to start, so I figured it was time for a top end

Took it apart and to my surprise the cylinders and rings were stock and looked really good. I honed cylinders anyway, did new gaskets, and threw in new rings.

Put it back together and it started effortlessly. So I hooked up water to it and let it idle for a bit in the driveway. Then I went and tried to blip the throttle, and it died with the water running. I quickly tried to shut the water off. blew the water out of cylinders and I haven't gotten it to run right since.

Decided I would rebuild carbs to check another thing off the list..

Still wouldn't run.

Then I got this other jetski, and took carbs I KNEW were working, and put them on the boat, still wouldn't really fire, This was at the point that I realized there was still marvel mystery oil in the crankcase. I siphoned that out with gas to dilute it. and yes I premixed the gas... and you know the rest.

 

[bdeemo]

When my key sheered it would turn over just fine too. Did you try spraying starter fluid in it if it won't start with that then something is wrong internally and not a carb issue

Yes that's exactly what happens. Maybe I should check the key.

 

[Ranchero50]

If you filled the cylinders with water you may have sheared it. Old troubleshooting theory is 'last thing first'. What's the last thing that happened to it before it ran like poop?

 

[CedarRiverScooter]

Your gutsy, vacuuming up gas . . .

 

[bdeemo]

If you filled the cylinders with water you may have sheared it. Old troubleshooting theory is 'last thing first'. What's the last thing that happened to it before it ran like poop?

Last thing that happened to it before it ran like crap was when I blipped the throttle with the hose running and it died. I took the hose off asap, and took plugs out to spray all the water out. good theory.

Yeahhhh my pooor poor shop vacc. haha

 

[bdeemo]

I guess I will have to check the woodruff key next week, after this fishing tournament I'm preparing for. Is the PTO easy to take off? I assume I have to take off the jet pump first-hand right?

 

[Ranchero50]

Mag is under the front cover. Pretty simple to access and remove if you made allowances on your build to get there. Mine has the engine electrical box sitting front of it. Remove the cover, block the flywheel and remove the nut. Pop the mag flywheel off and inspect the key etc.

 

[bdeemo]

Aw man my build won't be very friendly for that. Got about 6" of room in front of the mag until I hit my firewall.

 

[Ranchero50]

Oh well, looks like it's a great time to add a maintenance hatch.

 

[bdeemo]

PSG, I've read somewhere where you recommend egg crate foam for noise reduction. I'm sure that works well, but are you worried of it being flammable at all?

 

[PSG-1]

Not if you use the right type:

 

[bdeemo]

Chased down another loose end... the woodruff key looks great. Maybe it could be the coil? One spark looks stronger than the other, though both are bright blue.

Heres the key.

 

[bdeemo]

 

[bdeemo]

What is this plate and why is it covering one of my cylinder holes. I assume it's normal but it doesn't open when i turn it over