2000 Seadoo GTX Milenium Edition Low Compresssion

[matthewprenger]

After riding for a little while my seadoo ran real rough and died. I tried to start it again and it just clicked and didn't turn over. Got towed home and checked the battery. Charged it for a while and it still had the same problem. I manually turned the shaft on the back of the engine and at first it was really tough. I wedged a big screwdriver between the bolt heads on the wheel on the back of the engine. After spinning it for a few rotations it got a lot easier. I fired it up and it ran but it ran real rough. It had a clicking sound as it ran. Idled around the back of our cove and it would idle fine if I gave it some gas. Pulled it back on the lift and did a compression test on both cylinders. The front one showed 60 psi and the rear showed 140 psi. What could cause the pressure drop in the front cylinder? Would it be rings or something else?

 

[Dr Honda]

Normally it's the PTO jug that gives out... but it melted down. It could have overheated, been run lean, been run out of oil, or sometimes the rings just wear out.

Until you pull the engine apart... you won't know for sure.

 

[sodadoc]

Low Compression

I had the same problem with my 2001GTX RFI last weekend. I had ticking or light knocking sound from the front cylinder. It ran poorly and then barely ran on one cylinder. We were about fifteen miles down river and ended up towing back to our launch. I pulled the Rave Valve on that cylinder first and found it very oily and the end was chipped which I assume was either the ring from the piston caused or part of the piston. Anyway, I removed the head and found a hole in the piston like someone had put a torch to it and the part of the cam i was able to see was coated with metal that looked like it was baked on. I don't have a cause or any good advise to give other than don't run the engine anymore than you have too. The top end can be rebuilt fairly cheap. It sounds like you may still have a good chance of only repairing the top end. Be sure to find the cause. I'm still unsure of my failure!

Good Luck!

 

[matthewprenger]

well the mechanic took a quick look at it today and the bolts holding the exhaust manifold to the engine were loose and he thinks that water got down in the engine through there and since water doesn't compress it bent a rod as the piston moved up and down.

 

[Dr Honda]

well the mechanic took a quick look at it today and the bolts holding the exhaust manifold to the engine were loose and he thinks that water got down in the engine through there and since water doesn't compress it bent a rod as the piston moved up and down.

Nope. The water would have never gotten into the jug while it was running. But an open exhaust could have made it run lean enough, that it melted the piston edge.