I think I need a new 951

[RadsGSX]

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I have a Sea Doo GSX LTD with the 951 engine. It has 122 hard hour on it. Approximately 6 hours ago, I rebuilt the top end and now it appears seized. I don't know what went wrong! I am considering doing an engine exchange with you this winter, and I have a couple of questions.

How close to factory specifications are your engines rebuilt? Are they rebuilt a little "looser'" for extended engine life and warranty?

Do they come with the factory compression?

What will void the warranty?

Besides the carbs and intake, and the exhaust mainfold and exhaust, what other parts stay with the original engine?

I see you are located in Clearwater. I travel to MacDill with the Air Force. Is there any discount for picking up and dropping off the engine myself? We could arrange a time this winter when your business is slow.

Thanks.

[Bryan Glynn]

Picking up and dropping the core off locally saves you the shipping cost.

We need the cases, crank, cylinders, head, head cover and RAVE valves.

Why did you do a top-end? Why not the bottom as well?

Our engines are built with factory compression - the 951 has at least 150 psi cranking compression. Our piston to cylinder clearance is a bit more than stock, but well within tolerance.

Only disassembling the engine will void the warranty.

[RadsGSX]

I only rebuilt the top end because I wanted to get it back out on the water and becaue the crank looked good. Plus, I had a Rossier head on it and only 143lbs of compression. I hoped to only need a hone but the cylinders were warped so I went one over.

The engine never wanted to rev over 7000 rpms. It was a Rossier stage one kit and IMS modified carbs. I still use the stock pipe and impeller. I used to race Kawasakis and I've rebuilt lots of engines. I took my time rebuilding the 951 but it still seized. The oil injection and TPS are correct. I don't know what went wrong.

[Bryan Glynn]

Why were the cylinders going down, and did you take the crank out and fully inspect it? What about now - what seized?

[Bill O'Neal]

The new motor will sieze if you do not find the cause. First change the oil filter, then disassemble the carbs. If you find nothing wrong with the carbs, put a larger set of main jets into them.

If your rear clyinder is the one siezing, check the rave valve pulseline for a hole between the case fitting and the check valve.

Never operate a 951 at WOT when the fuel selector valve is in the reserve postion and the gas level is low. It will suck air into the fuel lines.

[RadsGSX]

I don't know why I had low compression. I bought the ski used from a friend (40 hours) and it never had high compression and never wanted to rev over 7000, even with a higher compression head.

I was running the exhaust hot to force a few more rpms and I may have run it too hot.

I did not pull the crank when I rebuilt it. When I turned the crank over by hand, it felt smooth and the rods were not discolored. I didn't think the crank was bad.

I have not disassembled anything yet.

The other day I was down on the river and after letting it warm up I did a full power run. After about 12 second, the engine 'dove over' and died. It restarted and I was able to make it back to the launch under my own power. When I got close to the launch, I increased the rpms. This time it died quickly at about 6000 rpms.

So this is my dilemma; do I try it again and rebuild the top end, or do I just bite the bullet and get a fresh engine. I do a lot of riding and a lot of spontaneous racing on the river. The ski is rarely under 6000 rpms. But, I don't beat it. I spend a lot of time tuning and tweaking. However, I don't want to spend a lot of time repairing it!

[RadsGSX]

I found a small clear piece of plastic in the inlet of the first carb. I didn't recognize it and don't know where it came from. The rest of the carbs are clean. They were just rebuilt and redone by IMS Racing. They have 167.5 mains so they are getting enough fuel.

I have never changed the oil filter. Honestly, I don't know where it is.

The rave valves are operating correctly.

Does the cost of a rebuilt 951 ($1099) include shipping?

[Bill O'Neal]

No, two way shipping is extra, usually about $160 to California for a 951 motor.