01 GTX stutter and white smoke

[Smanos22]

Went to go start the Jetski today for the first time all year with a brand new battery and at first it was just cranking and wouldn't turn over. Added a thing of sea foam and mixed some new gas in there and then it fired right up.

Out of the water it seemed to run fine at first but then when I would give it a little gas the rpms wouldn't drop right back down after letting off. It would take about a minute to slowly return to idle (1800-1900rpm).

Has brand new plugs in it by the way too and the gas that was in there was a year old before mixing in new gas and sea foam.

When I dropped it in the water to test it out, it would stutter and not rev over 2800-3000ish rpms(maybe misfiring?). I also noticed a lot of real white smoke coming out from the back. This is the best description that I can give but I'm lost at what it could be.

When it's out of the water it seems to reach higher rpms then when in. And the white smoke wasn't abnormal when it was on the trailer only in the water with load.

I plan on draining all the fuel and putting new gas in there but I believe it acted this way last year the last time i drove it.

I just replaced the wear ring, full jet pump rebuild and carbon seal. Not sure if that has anything to do with it but just adding that info.


I've had this ski for 4 years and never had any issues with it at all and only had to change batteries. Any help would be great so I know where to start to diagnosis this problem because I would love to get it up and running.

Thanks guys

-Steve

 

[Smanos22]

Today's update:

Just ran a compression test on it today, got 90 on both cylinders. Has no problem starting up or anything. I rented the compression tester from auto zone so I'm hoping that it's calibrated right.

When I pulled out the plugs (brand new) I noticed they had oil on them, and even the end of the compression tester

Any ideas on what the issue could be? Do I need a new top end? If the compression readings are right I understand that's deff the issue. I'm just confused as to why both cylinders are pretty much the same reading.

Also I noticed that some of my fuel lines are still the grey tempo lines. They look to be pretty gunky where it goes into the carb

Another thing I noticed is that the band clamp on the exhaust looks to be slide over a little. Could this of caused an issue that lead up to this?

And lastly, when It was hooked up to the hose today I noticed water coming out of the exhaust hole in the back, is that normal? I'm fairly new to working on skis and just want to make sure, thanks.

 

[Coastiejoe]

At 90 psi, at a minimum your top end needs rebuilt. 200 or less hours the crank should be ok. If near 300 hours, time for total rebuild. This is assuming the rented gauge is reading accurately.

Water should come out the exhaust when on the hose. Make sure you do it in this order. Engine on, water on, water off, engine off.

Grey Tempo fuel lines are engine killers. Replace them all and double check the carb filters since you just rebuilt them.

Did you use an OEM kit? Did you replace the pop off springs by chance?

 

[Smanos22]

I didn't touch/replace the carbs sense I've had it because I've never had any issues up until now. Maybe you saw "carbon ring" and just misread it. Thanks for the advice tho. Ski has 270 hours on it and I believe it was rebuilt once before by previous owner, not sure though. I bought it with 230 hours on it 4 years ago.

 

[mikidymac]

You have to get rid of the tempo fuel lines and rebuild the carbs immediately.
What plugs are you running? They don't look like BR8ES's.

 

[Smanos22]

I always ran those ngks but I grabbed these plugs because that's all the local store had for me to fire it up. They said they were compatible

I do plan on changing out all the fuel lines and rebuilding the carbs too

 

[mikidymac]

Get those plugs out too. There is no way they can be comparable with 3 different heat ranges.

You also need to try a different compression gauge because if you do actually have 90 pis carb kits aren't going to do anything but waste money.

 

[Smanos22]

I planned on using another compression tester just to be sure. But if I had to rebuild the top end I would do the carbs while everything is apart is what I'm saying. Do have any ideas what you think it is based of the symptoms I listed? Does that sound like something that would happened with a bad top end?

 

[mikidymac]

The symptoms you are describing are exactly dirty carbs and/or fuel system.
Unfortunately the results of running it that way are ruined top end and thus low compression.

 

[Smanos22]

Okay thanks, I will keep you updated on what I find out

 

[CTSeaDoo]

You will get 90 PSI if you run the test with the throttle closed... It must be fully open when you crank...

 

[Smanos22]

Thanks I didn't know that. Hopefully I can get some better numbers out of her now