1996 GTX problem

[driftedoffroad]

OK sorry in advance for long post but I think its important to get the whole story.

Picked up 96 GTX from a friend this year. It would idle but crap out and die when gassing it. Ended up being the fuel selector. Cleaned that out and it would randomly not reach top speed (6800rpms) When out riding one time it dropped down and wouldnt go above 5000rpms then eventually 3500rpms so I babied it back in. I think this is where the damage was caused, I'll explain more later. Ended up replacing the old gray fuel line. Rode around a few time and still had the same problem of randomly reaching full speed 6800rpms; otherwise was about 6400 doesnt seem like much but significantly slower. Then out one day and realized that runs the best on reserve. It did not bog when landing from wave and goes to 6800 no problem. Best it has ever ran then boom and it was down to one cylinder.
Compression is 130 and 16. Take motor out and piston and rings are shot but cylinder is ok. Did a top end rebuild, carb rebuild, and new rave valves. Also emptied gas tank of all old gas.
Ok so I was told to run premix on the first tank for break in and leave oil injection connected. Would not run like this my guess was too much oil. So I pulled the pump cable off of the carb. Takes a while but starts up. Runs right up to 3k.
Next morning go outside to start and click...click. Battery is good, but there is a puddle of gas at the bottom of ski. Take plugs out and cylinders are full of gas. Takes an hour and a half to get it started after this. But finally get it started. Decide to get it out on the water to test it. It revved up to 5000rmps fine (was told to stay under 5000rpms for break in.) The only thing is it bogs from 3500rpms to 4500rpms if accelerating slowly. Also the longer it idles the harder it is to get going again. Seems like when idling it is flooding or something and it has to overcome that. Then I remembered it was doing that right before it lost compression. I am totally out of ideas with this thing. Sorry for the huuuge post but I wanted all the info to be at hand because no one else can seem to help me with this thing.
Thanks in Advance,
Anthony

 

[kustomkarl]

Anthony, if you removed the injector pump cable chances are the pump doesn't have any oil in it to keep it from burning out... if you want to run it with the injector pump not working remove the shaft behind the pump unit. Did you replace the diaphragms and clean the internal carburetor filters? Look for an air leak in and around the intake area. I would do another compression test also.

Karl

 

[driftedoffroad]

I already had the carbs off once this year so I ordered rebuild kits and did that when the motor was out. didnt have time to check for intake leaks yet.

ok so heres the update though. I adjusted my idle to 3k out of water. the weird thing now is it doesnt seem to rev exactly right. if its idling and I snap the throttle it almost revs to 7k but if i try it more than once it wont get all the way up there. any ideas with that?
thanks in advance,
Anthony

 

[kustomkarl]

The seadoo has a rev limiter to keep it from over revving...expecially out of the water. There is no load on teh jet pump so it will rev up pretty quick out of the water.

Karl

 

[driftedoffroad]

ok I guess I never noticed it before. I'll have to wait til it goes in the water again. I'm just so used to having problems with this thing lol. Thanks for the quick reply.
Anthony

 

[kustomkarl]

Keep us posted if you think you still have a problem.

Karl

 

[driftedoffroad]

So I tried going for a water test yesterday but I couldnt get it started before my battery was dead. It again had too much gas in the cylinders and by the time it was all out it wouldnt start.

Charged the battery overnight and went out today to see how it was. (had left the gas off this time) took a minute but started chugged a little with no response from the throttle. Then it ran ok but idle is now back around 1200-1500. Also it will now not rev past 5500. I dont know where else to go or what to do. Any suggestions?
Anthony

 

[kustomkarl]

Is the engine broke in yet? When you replaced the RAVE valves did you leave them set as there were? What is the pre mix your using now? 40:1 is about best if you pre-mixing. Check to be sure the carbs are in sync, and getting full throttle when you advance the throttle when it isn't running. Look in the carb throat and see if it is going to full throttle. Let me know what you find and how you make out.

Karl

 

[driftedoffroad]

ok yet another update lol. to answer your questions:
I went through one tank of 40:1 premix.
I replaced the valves and set them to be flush.
Then I sucked it up and went through checking things again.
I pulled off the rave valves thinking maybe the premix had restricted them from the buildup. They were oily but ok. I wiped them off and moved on.
I pulled off the aire box and flame arrestor. Then adjusted the idle screw according to another thread (just touching then two turns). Carbs are good and in sync. Started it up just bare carbs and it ran perfectly right up to 3k then will blast right through the revs no problem.
So then I figured maybe the flame arrestor was restricting airflow. cleaned and blew it out and started re-assembling and then starting one component at a time. Good up until the airbox lid. When the lid is on it doesnt rev as high and doesnt sound as good as when its off. It runs the best without anything on it though. Is it ok to run with the lid off?
Sorry for the long post again but this is the most headway I've made so far.
Thanks in advance,
Anthony

 

[kustomkarl]

The Spark Arrestor and air box must be kept in place for a safety issue...It could back fire and cause an explosion! Never run it without the spark arrestor and air box in place. It could be that the engine is still tight and not broken in just yet. Were you running pre-mix before you had problems...I forget if you were or not. The injector is a variable oil injector pump that delivers oil at a variable rate depending on RPM's of the engine. With pre-mix it is at a constant rate...sometimes it's too much other times it's just right. It will always be 40:1...run it some more and see if it doesn't loosen up and get higher revs in the next tank or 2. Keep an eye on the spark plugs and go have fun.

Karl

 

[JPX]

Try another set of spark plugs. You might have loaded yours up and that may be impeding their ability to fire correctly at the higher revs.