newbie help, gtx di will only go 40mph

[scunnyseadoo]

h i have recently purchased my first pwc, a 2002 seadoo gtx di, with only 60hrs on it, in excellent condition, totally faultless, so i thought! on the first outing , the ski only managed to pull 40mph, at around 6750rpm, I was hoping the ski would have better performance than this. I contacted the 'jet shed' and they suggested I have the pump and impeller inspected by them, I took it to them and they repitched the impeller and gave the wear ring the all clear. I refitted the pump, took the ski back out, hoping for increased performance but its still the same, still does 40!! even on gps .... has anyone got any ideas on where to check next?

 

[jhjesse]

JMO
Sounds like cavitation to me. With those RPM's you should have good speed.
Why did they not replace the wear ring?
Did they check the drive shaft and make sure the splines are in good condition and fully engaging?
What kind of impeller did they install and why no new wear ring to go with it?

With a stock impeller and a new wear ring, your ski should jump out of the hole and light it up.

 

[wampaku]

Do you have the learner key? Or the regular key?

 

[LouDoo]

If the wear ring is good and you have no more clearance .004 between the impeller and wear ring. The next thing I would look at would be the carbon ring.

Lou

 

[scunnyseadoo]

The impeller is stock , the wear ring had very little wear (20thou) when you say carbon ring is that the seal between the pump and the hull? How can I tell if it's cavitating
I am using the yellow dess, and the splines on the prop end of the driveshaft are like new

 

[LouDoo]

Cavitation is when the motor is running at normal RPM but the ski is not moving or not moving as it should, over revving. Kinda like in your car when the clutch is slipping. It is usually caused by something in the drive system.

I have replaced the carbon ring through the process of elimination, however I recall Dr. Honda having some method, to tell if it is the carbon ring, he will probably see this post and respond if not PM him, I'm sure the will tell you.

Lou

 

[rotaxrule1]

Cavitation is when the motor is running at normal RPM but the ski is not moving or not moving as it should, over revving. Kinda like in your car when the clutch is slipping. It is usually caused by something in the drive system. I have replaced the carbon ring through the process of elimination, however I recall Dr. Honda having some method, to tell if it is the carbon ring, he will probably see this post and respond if not PM him, I'm sure the will tell you.
Lou

Ya, if I recall correctly, he smears a little waterproof grease around the carbon ring to see if it improves anything. It won't last long but enough to tell you what you need to know. (reason I remember is because I might have to do the same thing)

 

[scunnyseadoo]

I would like to know this method before I spend any more on the ski !

 

[scunnyseadoo]

I have been under the ski today having a look for anything that may cause cavitation, cannot see anything out of place, the carbon ring looks ok and not grooved, some of the silicone around the grate and ride plate is a little shabby but surely that cannot cause any issues, It is fitted with a hull protector, could this cause any issues? its driving me mad

 

[Kozerxp]

To see if the carbon ring is bad you need to smear sone water proof grease on the collar and give it a go if it performs better you will need to replace the carbon collar

 

[scunnyseadoo]

today I have had some success with the ski! I was running out of options, tried the carbon ring/ grease trick, no change, I then started looking at the OPAS paddles, I zip tied them in the up position and took the ski for a spin, it was clocking 45 on the clock , around 53 on the gps, there maybe still some issues with the ski but its certainly quicker than it was! also with the paddles up it turns a lot quicker and is a hell of a lot more fun to ride, a lot easier to spin out and planes off a lot better, I think I am going to buy the OPAS removal kit and also replace the wear ring, I checked the clearance and it was .002 to .003 ,replace plugs and clean out the tank as i noticed a little mid range misfire, so it may may still be causing a loss of power. can anybody tell me where is best to get the opas removal kit from that ships to the UK?

 

[LouDoo]

Whats an OPAS???

Lou

 

[Dennis]

Make sure the reverse gate is all the way up.

 

[scunnyseadoo]

OPAS is off power assisted steering , it gives the ski a bit of steering when your not on the gas, then as you give it some, it relies on watwer pressure out the back of the nozzle to lift up the 2 rudders located on the rear corners of the ski. as for the reverse gate, I was going to remove it temporary just to eliminate it from the problem !

 

[scunnyseadoo]

Further to my existing problems , today the ski began to run rough, misfiring and would not rev up, I took the seats off and discovered the engine compartment half full of water! I drained it out and found the pto rubber boot was badly split, stripping it down I noticed the drive shaft is bent , quite badly!! I ain't certain but I think this could be the cause of the loss in top speed? Has anybody had this problem? There is no signs of recent damage to the shaft so I'm guessing this has been like it a while !

 

[jhjesse]

Further to my existing problems , today the ski began to run rough, misfiring and would not rev up, I took the seats off and discovered the engine compartment half full of water! I drained it out and found the pto rubber boot was badly split, stripping it down I noticed the drive shaft is bent , quite badly!! I ain't certain but I think this could be the cause of the loss in top speed? Has anybody had this problem? There is no signs of recent damage to the shaft so I'm guessing this has been like it a while !

Sounds like you have found the problem. Good luck!!

 

[deepdiver]

Sounds like you will surely need to replace the pto boot, carbon seal and shaft. Hope that's all.
Don't know who you bought it from but he wasn't honest. Hope the price was right.