Looking to solve a WOT RPM issue...last season had some acceleration and hesitation problems...after a new "used" complete carb rebuild, grey line replacement, replaced fuel filters, and fuel selector...acceleration seemed solved, however, found that WOT RPM only got to 6200 rpm. Now targeting RAVE valves...found one did not even have a spring! ordered and put in. Now the question...when pushing on each of the RAVE valve bellows...each go "in and out"...but one is more "resistant" than the other...should they be the same? Assume they should be cleaned anyway...advise?
99 GTX LTD Rave Question
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SabrToothSqrl
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the 99 GTX LTD has a 951, and should reach 6800-7000 WOT with a stock prop. My solas concord will let it hit 7,200 WOT
check your RAVEs and water regulator.
of course, as engines age, they tend to lose power, how many hours are on it? I chased that last 400 RPM for almost 2 years before selling the ski and buying one with less hours (cheaper than an engine rebuild) lol.
check your RAVEs and water regulator.
of course, as engines age, they tend to lose power, how many hours are on it? I chased that last 400 RPM for almost 2 years before selling the ski and buying one with less hours (cheaper than an engine rebuild) lol.
Thanks for replying. She still has less than 100 hours on her...stock prop...I looked at the water regulator...spring was there in one 1 piece, bellow looks to be intact, moves up and down a little. I'm going to order the RAVE kit (gasket, bellow, o-rings) so I can have at least new gaskets and parts if needed...then do the cleaning.
Some additional history...prior to having a local seadoo dealer do the carbs and fuel system, while she did not accelerate as she should, she would get up to 6800 and 54mph (speedo)...since the carb rebuild and fuel system work...limited WOT RPMs. They checked compression (125 each)...Is it possible "they" messed something up? Or is it just a coincidence and one thing being "fixed" exposed another weakness?
Some additional history...prior to having a local seadoo dealer do the carbs and fuel system, while she did not accelerate as she should, she would get up to 6800 and 54mph (speedo)...since the carb rebuild and fuel system work...limited WOT RPMs. They checked compression (125 each)...Is it possible "they" messed something up? Or is it just a coincidence and one thing being "fixed" exposed another weakness?
SabrToothSqrl
Well-Known Member
Run with the caps off. Which should give you poor low end but max top.
Check the one way valve under the engine and the air lines. They both like to melt. Also check the rave solenoid.
Check the one way valve under the engine and the air lines. They both like to melt. Also check the rave solenoid.
That's a great idea! Curious though...I saw in a different post that someone also found that a spring was missing...is it possible that some shops take one out to "smooth out" the power curve? Loose some on the top and some on the low end but is smoother? I'll also look for the check valve and solenoid.
Still a little cold in the north east...may be a while before I can take her on a test run.
Thanks much for the advise!
Still a little cold in the north east...may be a while before I can take her on a test run.
Thanks much for the advise!
SabrToothSqrl
Well-Known Member
I don't suggest that, as if one piston is making more power at a given point than the other, your crank / engine won't last long...
Dr Honda
Well-Known Member
Nope... if you remove the spring... there is a good chance that you won't break 4500 RPM. You need the valve closed to build torque.
If you want it to run smooth... turn them all the way in. That way, you will have good control, and then they will pop open at the last moment to give you that crisp top end.
If you want it to run smooth... turn them all the way in. That way, you will have good control, and then they will pop open at the last moment to give you that crisp top end.
SabrToothSqrl
Well-Known Member
essentially, yes. It will hit max RPMS, but it will take longer to get there. the idea is to see if they are actually opening all the way by removing the resistance from them opening. I've done this while chasing that last few RPM. It's to see if they are even trying to open.
Did u check the solenoid? air lines? one way valve? Mine had a huge 3" long crack in the air line right off the engine. I also moved my 1 way valve closer to the solenoid so it's easier to inspect.
Did u check the solenoid? air lines? one way valve? Mine had a huge 3" long crack in the air line right off the engine. I also moved my 1 way valve closer to the solenoid so it's easier to inspect.
Update: With the missing spring replaced, took her on the water...still did not get over 6140 RPMs (about 50mph on speedo). With the ski on the hose, took the RAVE caps off and witnessed them going in and out pretty nicely (smoothly as I rev'd throttle)...and hit 7200 RPMS! Why the difference in/out of the water? So, got around to cleaning them...after running on the hose, they were pretty "moist" with oil (as a matter of fact, when I took the air hose off, it leaked oil? Normal?) and definately had a bunch of carbon build up. Cleaned up OK (there are some very small imperfections on the valve) with a plastic putty knife and some break fluid. Ran on the hose again...saw 7200 RPM...not sure if their was much difference in how she ran (engine sounds and feels good/strong)
As far as I could tell, hoses looked and felt intact (since they went in/out smoothly...this implies all that is working...right?).
What else can I check? It appears that it's not the RAVE...right?
As far as I could tell, hoses looked and felt intact (since they went in/out smoothly...this implies all that is working...right?).
What else can I check? It appears that it's not the RAVE...right?
SabrToothSqrl
Well-Known Member
7k out of water means nothing, there's no load on the engine... Jet pump assembly look good? Bearings? Wear ring?
I am questioning myself on what I saw with the RAVEs...on the hose, with the caps off, as the throtle was pressed, they moved inwards. As RPMs increased, they moved in...and I let off the throttle ahen reaching 7200 rpm...but, I don't recall them "popping" out. Is my direction on these mixed up? Is "in" = closed and "out" = open, right? Would normal operation be to see them move in until they hit the 3500-4000 and then "pop" outwards? Perhaps I still have some troubleshooting to do... On the water...I don't experience a "surge" as I pass mid throttle that I can feel.
I just checked again...it must be right. With the connector to the solonoid off...they just stay "out"...and the engine does not rev up as much. With the connector on, at around 3500-4000 they "engage" and move in rapidly...and the engine rev's higher.
I just checked again...it must be right. With the connector to the solonoid off...they just stay "out"...and the engine does not rev up as much. With the connector on, at around 3500-4000 they "engage" and move in rapidly...and the engine rev's higher.
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