1996 GTX cut to 5500 RPM while riding

[ractrev]

Hello,

I have searched threads here, but have not run across my exact issue:

I bought this machine earlier this year, and with a great deal of help from all of the information here, I went through the entire fuel system and the ski has been running and starting flawlessly.

Yesterday, I was cruising across the lake at about 50 MPH, and all of the sudden the RPM's dropped to 5500. The machine still starts, runs, and accelerates great, but 5500 is the highest RPM it will go (can't go over about 35 MPH). I understand some of the possible causes, but to have it happen while riding in the middle of the lake out of the blue, and still be starting and running well - I am stumped! Any thoughts?

 

[etemplet]

Check the rave valves. I've had one get stuck open and it melted the piston instant power loss for my 1996 GTX. RPMs were affected and 5500RPM is where the valves begin making a big difference. Actually 5000rpm but close enough. Good Luck !

Problem was my fault because I didn't check the movement of the rave after I tightened the screws down. I believe the gasket hindered the valve from moving freely.

 

[ractrev]

Thank you! This is what it feels like to me as well - I know this feeling from my old days of ski doo snowmobiles. I just don't understand during a full throttle pass on the lake, it would just happen all of the sudden, unless maybe the blade(s) actually fell to a closed position while riding (?). Anyway - will look at those first.

 

[ractrev]

Update here because I am still battling this issue:
Rave valves checked, cleaned, and bellows replaced. No change in my symptoms.
This thing can (and has) run all day like this. Just this last Saturday it probably had 3-4 hours put on it running like this. The carbs were done pre-season, as well as all new fuel lines, fuel filter and housing, and selector valve. Compression is 155/158.
Ready to bring it in to a shop to see if they have any ideas - but thought I would reach out here again first.

 

[POPPS]

Try running your in line from the pickup, directly into the carb?

 

[ractrev]

No, I have not tried that. I figured with a new valve, filter & housing, and all new lines delivery would not be my problem. Easy enough to try I guess.

 

[GGuillot]

No, I have not tried that. I figured with a new valve, filter & housing, and all new lines delivery would not be my problem. Easy enough to try I guess.

Just a guess, ck to see if the carbs are opening all the way with the throttle cable. I've heard of the piece in the top of the steering where it connects slipping loose causing this..

 

[Lothsahn]

Check the regulator. I had this exact same problem with my 96 GTX. A bad regulator will cause that.

See my thread:
1996 GTX Surging and won't rev

 

[ractrev]

Regulator the same as rectifier? I did order a new one of those just in case (cheap enough to try)

 

[ractrev]

Just a guess, ck to see if the carbs are opening all the way with the throttle cable. I've heard of the piece in the top of the steering where it connects slipping loose causing this..

Hmm, easy enough to look at that too - thank you

 

[Lothsahn]

Regulator the same as rectifier? I did order a new one of those just in case (cheap enough to try)

Yes, I meant rectifier. It's essentially the voltage regulator in a sea doo, and if you look at my thread, you can see a cheap one that I bought. It has mixed reviews but is working well for me.

It can be easily tested in 2 minutes with a multi-meter, out of water, if you have one. See the linked video.