Lost speed YTY

[sc419795]

1998 GTX Limited. Was hitting 61-62 pretty consistently last year. Now - low 50s. With 2 on it - 48-50. RPMs at 6590 yesterday with just me on it getting 49 MPH. The one thing I noticed is I could hit these RPMs and probably be at 75% of throttle. I would peg it - and see little/no change in RPMs and/or speed increasing.

Looked at the manual and rev limited is 7000 RPMs. Not sure if I should be getting more than 6590 or not. Any ideas on why I would lose power year to year?

 

[JJinSC]

Check and clean the RAVE valves. It sounds like they may not be sliding open.

 

[sc419795]

Would there be a way to add a fuel additive to clean the RAVE values - or should I follow the directions posted elsewhere on this site?

 

[El Toro 33809]

Clean them manually per the instructions found here.

 

[JJinSC]

And make sure you are running the right kind of oil.

 

[sc419795]

I am running the black jug of Quicksilver - full synthetic. I believe I had previously read about that on this forum. Is this the proper oil?

 

[brock1]

Before you switch the oil just clean the rave valves they come apart pretty easily and that will most likely make the biggest difference

 

[El Toro 33809]

Full synthetic is good. If the RAVE valve cleaning doesn't do the trick, check that the carbs are clean.

 

[sc419795]

So either I need to get over my fear of turning a wrench on that machine, or pay big $s to have it corrected. I did read the step by step and I do have a manual. I am not that mechanically inclined. If I took it to a shop to have done (cleaning the raves) what am I looking at in a repair bill?

 

[brock1]

So either I need to get over my fear of turning a wrench on that machine, or pay big $s to have it corrected. I did read the step by step and I do have a manual. I am not that mechanically inclined. If I took it to a shop to have done (cleaning the raves) what am I looking at in a repair bill?

they will tell you that it is a big job and charge you alot i gurantee it. But the best thing for you to do is get overe that fear and try to do it yourself. The worst that can happen is you knock them a little out of adjustment and you have to get back on here and ask our opinion and well help you the best we can to set them right again.

 

[JJinSC]

I am running the black jug of Quicksilver - full synthetic. I believe I had previously read about that on this forum. Is this the proper oil?

Just make sure it is not the TCW-3, but the API-TC low ash.

 

[El Toro 33809]

they will tell you that it is a big job and charge you alot i gurantee it. But the best thing for you to do is get overe that fear and try to do it yourself. The worst that can happen is you knock them a little out of adjustment and you have to get back on here and ask our opinion and well help you the best we can to set them right again.

I agree with Brock. It is a fairly easy job. Perhaps someone from the forum is in your area and could give you assistance.

 

[jhjesse]

I would think that at 6950 rpms and loosing speed would indicate a wear ring or pump cavitation problem...JMO

 

[sc419795]

RPMs are 6,590....not 6,950. Not sure if that clarifies your comments. Also - is there a way to search members for my area?

 

[jhjesse]

Oh...blew that one! Hate it when that happens. I guess I was having a 70's flash back while reading the post.
I would still check the wear ring clearance. My 99GTX with my fat butt on it will get 6750rpm's and 60+ on speed.

 

[sc419795]

We were getting 60+ mph last year. Only mid 50s this year and my fat butt is around 50. :lol:

 

[sc419795]

Guys - going to try and tackle this job myself. I have a few questions based on the shop manual and a number of posts I have seen:

1. Can the rave valves be cleaned without dismantling the entire part - in other words, can I pull the 2 (actually 4) allen screws - pull the entire valve out, and clean the paddle vs. dismantling the entire valve? I know it may be a short cut - but - remember the original post where I am mechanically challenged? :lol:

2. How do I clean the "slots" within the engine where the paddles fit into? Do I need to be careful on how much Carb Cleaner I load up in there?

3. In looking at my engine, I know there is a gasket between the rave valve and the head - it looks like it could be more of a liquid type of gasket vs. a hard one. I assume I should have some gasket material available. Is there anything in particular I should use, not use?

4. In many of the threads, it talks about a very thin coat of oil coating on the paddle once I have cleaned it up. I assume this is the normal PWC oil that I am using - which is the Quicksilver full synthetic in the black jug (make for SeaDoo products).

5. How tight do I put the allen bolts back in? Is there a specific pound I need to tighten to, or just tight with some loktite?

I sure appreciate all of your help/support on this guys. Sorry to be a pain but I just don't want to screw this up. :thumbsup: