1996 seadoo GTX fouling plug in front cylinder

[JetSkiSeeker]

Hey guys,
Last time i posted a question on hear the response was fabulous! thought i would give it another shot. Took out my ski this weekend after changing my impellar for a cavitaion issue. Now it looks like i am fouling the front cylinder plug after a short amout of time on the water. I guess my question is where to start on this? is this a simple carb adjustment or a more serious issue? any help would be appreciated.

Thanks

J

 

[kustomkarl]

First off what is the compression of the engine? It should be ideally 150 PSI per cylinder. If the compression is good it might just be a carburetor adjustment. Did you try to just replace the fouled plug and get another reading?

Karl

 

[JetSkiSeeker]

Havn't checked the compression yet due to the fact that it seems to run really good up to the point of fouling a plug,What will compression tell me about this situation? for future referance. i did replace the plugs and again after a twenty min ride or so that it fouled again (very black) where the other plug remains white. I did however notice that the last time it did this that the back plug was loose (my bad didnt tighten it down all the way) and was unable to try again due to bad battery (on its last leg). Thats the run down on my experience. Will i cause more damage by just changing plugs and running it till it fowls again?


P.S.
Thanks again Karl to the fast response your response was AWSOME on the cavitation issue i was having.

 

[JetSkiSeeker]

One more quick question, i lost the manual would anyone know what the gap is supposed to be on these machines they are new to me i have been a kawasaki guy up till last year?

 

[kustomkarl]

I would either replace the battery or be sure it is in good charging condition. Have it Load tested to be sure it is a good battery. Make sure the carbs are tight and no air leaks anyplace. Your plugs in the 96GSX are I think NGK BR8ES, so the gap is 0.5-0.6mm or .020-.024in. If the compression is low in one cylinder it could cause a fouled condition that means other problems, like a worn set of rings for instance.

Karl

 

[JetSkiSeeker]

I said it once and i'll say it again Karl is da man! Thank you sir. looks like i have a little homework to do.

 

[kustomkarl]

If you need advice on doing a proper compression check give me a shout...I'll help you out.

 

[JetSkiSeeker]

Awsome would you mind giving me the run down just to make sure i do it right the first time? And one more question on the spark plug gap, Would having to big a gap cause a plug to foul faster then a spark plug with the right gap? After reading are conversation i defanatly have been gaping them to much.

Thanks Karl,

J

 

[kustomkarl]

Gap them both the same ... don't just guess. It changes the heat of the spark.

You'll need a compression tester. Go to Auto Zone. I think they sell for like $25.00. The compression gage, will screw in the cylinder head in place of the spark plugs. To test compression, remove both spark plugs. Place spark plug caps on the plug cap studs near the cylinder head to ground the empty caps. This completes the circuit of the ignition electrical system and prevents any electrical problems from the caps being un grounded. Using the correct adapter for the threaded end of the tester,( same length of the spark plug threads length)Screw in the tester in one plug hole. Hold the throttle wide open. Push the start button. Watch the compression gauge, when it peaks out at the most compression, let go the start button. Read the psi number. I would do it 3 times to be sure it is accurate. Check both cylinders the same way. The ideal compression is 150 psi per cylinder. If it is less, it's not a problem as long as they are close to being the same. If the psi is less than 90 it might need be time for a tear down and a rebuild. If the psi in 1 cylinder is say 140 psi and the other is 80 psi you need to tear down and repair. This difference is a lot and there is a problem. I hope this helps you.

Karl

 

[BCSwider]

96 challenger water in cylinder

I bought a 96 challenger that hadn't run for a year. The rotary valve was seized but the engine looked good so I had it broken down, cleaned, and put back together. The boat ran fine for an hour then the o ring on the cylinder head split dumping water into the rear chamber. A new o ring fixed it for another hour untill that one went, and there was water in the chamber again. I replaced it and it ran fine for 1 minute until at full throttle i was only getting 3000 rpms. Pulled the plug, no water. Cleaned and replaced it, 1 minute of running perfect then the same thing happened. The boat is loosing the rear cylinder after a minute of running fine, no matter how many plugs I change. No one knows what is happening and my boat is sitting in the driveway. I cleaned the fuel filter, the carbs were cleaned a week ago, there is spark in both cylinders, no more water is getting in through the head, and I have 180 psi in both cylinders with an r&d head. I need serious help or this thing is going to drive me crazy.