2000 RX, Low compression, rings?

[CaptKaos36]

Hi everyone,
My friend had his ski sit for a couple of years and asked if I would try to get it going. I checked the spark plugs and dropped some gas in cylinders. Ski fired and ran for a second. I shut it off and figured it was going to be an easy fix. The next morning, backed into the ramp and it wouldn't fire at all. At my shop I tried again and nothing. Added more gas in cylinders and no fire. Checked for spark and was a faint orange. Compression in the cylinders is 50 psi, I am figuring the rings need to be changed. I also tried putting a jump charger on the battery and still no fire. Do you feel it's the rings also? Rave valves? I wanted to ask here, because I am more of a boat mechanic, even though I have rebuild several pwc engines. Upper build kit is $269, Can I do it without pulling engine? Thank you for any answers or advice. So much for easy fix.........

 

[burtshaver2021]

At 50 psi it’s time for a rebuild, are you dropping straight gas in the cylinders or pre mixed? The only way you’re going to know if all it needs is rings, is by measuring, probably going to need a bore but worth measuring. I’ve heard that on these 951’s it’s a no no to do too ends only. Just a few precautions with these, don’t run them out of the water for anymore than 45 seconds even if you have it hooked to hose, don’t run garden hose unless engine is running, don’t boost them from running vehicle or booster pack

 

[CaptKaos36]

I dripped in gas with oil. Can I replace the rings without removing the engine? I figure the more I check, the more I will have to rebuild.
Removing the engine is my main question so for. Ski was running and being used when he put it away.
Thnaks

 

[Grim]

Did you use a good compression guage...50 PSI is way low. We normally rebuild at about 120 PSI. go to auto parts store and rent one for free. Make sure you hold the throttle to wide open when doing the compression check.

 

[burtshaver2021]

I dripped in gas with oil. Can I replace the rings without removing the engine? I figure the more I check, the more I will have to rebuild.
Removing the engine is my main question so for. Ski was running and being used when he put it away.
Thnaks

Yes, you can replace the rings with the engine in the hull

 

[CaptKaos36]

I have a good compression gauge, I thought it was really low also....
I did have the throttle wide open and booster charger on the battery to be certain. Rave valves???

 

[mikidymac]

So as said above never ever jump or boost these or you will fry the computer.
Is this a carbed ski or fuel injected?

If your compression is actually 50 psi then you have mechanical damage to the cylinders and no rings will not fix it. New rings does nothing on these, you have to bore oversized and new oversized pistons and rings. Also if higher than 100 hours you need to rebuild the crank and balancer with the top end on a 951.
Weak spark has nothing to do with your low compression.

 

[tomanycars]

I dripped in gas with oil. Can I replace the rings without removing the engine? I figure the more I check, the more I will have to rebuild.
Removing the engine is my main question so for. Ski was running and being used when he put it away.
Thnaks

My 787 was running but having a ard time staying running and bogging. I thought the same thing but both skis had low compression. pull engine total rebuild. crank shaft was coming apart

 

[lavasioux]

At 50 psi it’s time for a rebuild, are you dropping straight gas in the cylinders or pre mixed? The only way you’re going to know if all it needs is rings, is by measuring, probably going to need a bore but worth measuring. I’ve heard that on these 951’s it’s a no no to do too ends only. Just a few precautions with these, don’t run them out of the water for anymore than 45 seconds even if you have it hooked to hose, don’t run garden hose unless engine is running, don’t boost them from running vehicle or booster pack

Hey Burt is this the same for a 717? Should it only be run with hose connected for less than a minute?

 

[burtshaver2021]

Hey Burt is this the same for a 717? Should it only be run with hose connected for less than a minute?

Hey @lavasioux . Yes, same for the 717’s I would guess it’s more important for seadoo’s with the carbon seal seat up, but it does go for all seadoo’s

 

[lavasioux]

Hey @lavasioux . Yes, same for the 717’s I would guess it’s more important for seadoo’s with the carbon seal seat up, but it does go for all seadoo’s

Thanks Burt!