Please help to diagnose the engine problems with LS2000

[Cobra Jet Steering LLC]

Actually being within 5 psi is normal if the cylinders are good but it's way TOO LOW , they need 80 to even run. Thus the test is not good. black and wet plugs could be caused by a number of things. Another big thing to learn about on the 2 strokes is the oil lines falling off and blowing your engines. VERY BIG ISSUE.

 

[Cobra Jet Steering LLC]

Haaa for all the old board people, I'm starting to sound like steve45, he would have sent you all the links for all the known issues on the 2 stroke boats right off the bat, not that it's a bad thing but just brings back memories.

 

[Gmmastertech1]

Steve, is that you? Lol Kidding Jeff. I was thinking the same thing! To the OP, curious to see what your 2nd compression readings are.

 

[malashev11]

just ran the test and they're all 90. all 6. so now i was wierded out that they were the same again. its hard tp imagine that out of 6 cylinders all 6 are broken the exact same way. they were exactly 90. I checked battery charge and both batteries are bellow 20% and i know low bat can cause low pressure readings so i am charging them. at least 1 at 100% would give me a more accurate reading. also if they're the same broken then why is one acting so much worse than the other.

could anyone thorize why it would stall out in the water but if it sits on the trailer run just fine, after a few attempts if it was in the water very recently. and shaken up theory doesnt work here because it just got driven through some pretty crappy dirt road. trailer bottomed out a few times. i'm just having hard time coming up with ideas other than engine doesnt have enough power to turn the impeller in the water vs dry.
i also know that intermediate bearings are leaking, i was planning to replace them at the end of the season when its too cold to play in the water but not cold enough to play in the snow, could that cause this behavior. I am assuming it could cause the extra shaking at idle just like any bearing could.

all this help is very much appreciated. if it wasnt for you guys i would f had 2 engines ordered already and possibly 3k out

 

[Cobra Jet Steering LLC]

Possibly the rear hatch switches are out of adjustment killing the ignition, another common problem. your compression is probably going to be around 100 to 110 with a good battery.

 

[malashev11]

is there a wirte up on how to convert ot pre mixed fuel? do i need a different fuel pump, diff fuel filters, carb parts? does the oil pump system needs to be removed or could i leave it on?

 

[malashev11]

so the rear hatches cant be out of adjustment since i think the right engine hatch is bypassed. i could unplug it completely and it starts and runs

 

[Cobra Jet Steering LLC]

I am sure someone has written up what you need to do but for now locate your primary problem adjust the rear hatch switches also check your engine grounds and the lanyard switches.

 

[malashev11]

i'm not sure where and how it is done, i just know it doesnt need to be there at all for the right engine to run.

 

[malashev11]

how to adjust them?

 

[malashev11]

someone recommended a quarter. is that a valid option still?
also what other things could it be. I'd like to do as many things as i can before going to the lake since i can only do this once a week and the problem doesnt exist on the trailer.

 

[malashev11]

i checked all grounds i could find, and safety thing, all good.
but i think you guys might have been right again about electrical part. One of the batteries is charged to 65% and it idles waaayyyy smoother. I mean virtually no vibration. could that be the cause? dead batteries. i've seen some dying batteries cause some weird stuff on cars before, like cutting power at high throttle.

 

[Yamatuf]

Eliminate each step one by one to find the root problem. I'm a big 2 stroke fan, they are easy to work on and I do most of all my work besides boring out new sleeves.

I use Island Racing block off kits. If you have to remove the engines it would be a good time to install. I completely removed my oiler tank and lines. Just finishing up dual battery install, tower and sound system. Rebuilt carbs and pumps, new plug wires n coils. If you remove the engines, PM me. There are a few water veines you will want to check. I believe it was 4x15mph did a great job on posting his findings to clean put water veines. I just removed my motors to clean and both were clogged not allowing any cooling at at the exhaust lower port(item 6) Some of my isues could have been the thermo sensor kicking in. I have pictures if needed when you get there. Start with compression first, root to all evil.

 

[Ronald Dillow]

I have good compression, but half way through summer my boat started doing the same thing. I was told to replace the CDI unit.

 

[4x15mph]

@Ronald Dillow , post a new thread if you need help with walking through your problem. I couldn't tell if you have a problem or if you were just posting that a new CDI could be a fix to this posters problem.

Cooling system (holes/veins) is definitely something that everyone should do with these 1999/2000 boats. I would also add strainers as a preventative measure.

 

[Ronald Dillow]

I took both exhaust completely apart after our final outing and I did have blockage, however the blockage was in the good engine. The exhaust were completely rebuilt with new gaskets and are so clean you could eat off of them.
I'll start a new thread.

 

[Felix hinojosa]

Does anyone know if malashev11 ever find out what problem was with his engines turning off while in water idling.

 

[Speedling]

Don't know if he did or not. Just saw this for the first time!
I know my exciter hated idling out and would put too much oil in the mix. I used the pump WITH UPGRADED LINES.
Never stalled out like that but didn't like it much.

If it were my boat, i would pull the engine to inspect everything anyways. Tearing the motor apart is just barely harder than pulling apart the pump.
This way you know what damage you may have. Also a good time to rebuild or get new carburetors.
Had my buddy help me pull engines out and then we had fun putting jet ski go fast parts back in. I wouldn't doubt it was more like an exciter 300 when we were done, lol!

 

[M@__]

Both of my 135hp motors shake like crazy. I really avoid 2000rpm but they both run great. The ski guys talk about how shaky they are too.

Speedling, what do you think the biggest improvement you made was?

 

[Speedling]

Mill the heads and my buddy tuning the carbs.
I also had all cylinders bored out .60 i believe it was.
Had performance cranks as well from "hot rod" i think it was?
Ports were all cleaned up and gasket matched too.

I had bought the boat that looked great but engines were blown. Found used performance waverunner parts for most everything as everyone was going to the supervharged stuff.

Once the garag is done there may be room for a project again...