Rebuilding a carb 787 - problem with RV seals

[Charlie_gtx]

Hello everyone,

I'm rebuilding the engine of my 1997 Seadoo GTX. I've installed a rebuilt crankshaft, as well as the rotary valve shaft and the balance shaft. I sealed the engine block with Loctite 518, following all the instructions in the manual.

The problem is that before installing the cylinders, I tried plugging one of the oil inlets to the rotary valve shaft and blowing air through the other inlet using my lungs and I can hear air escaping through one of the cylinders.

I believe that if I finish assembling the engine and perform a leak test, the result should be ok if the rest of the gaskets are in good condition. However, I think I might have an oil leak from one of the internal crankshaft seals.

Is the test I'm doing correct? Is there anything else I can do apart from opening the engine again?

Thank you and greetings from Spain

 

[mikidymac]

You should not have air escaping the rotary cavity.
Sounds like you are going to have to split the cases again.

 

[Charlie_gtx]

Thanks for getting back so quickly.

I'll keep you informed.

Thank you!

 

[Charlie_gtx]

The problem has been solved. One of the seals didn't seat properly.

Now the engine is fully assembled, and the leak test is okay, but I have an issue with the rotary valve.

I know it should be at 147 and 65 degrees, but the closest I can get is 143.5 and 67.5 degrees.

If I turn the valve, the results get worse.

The manual states a tolerance of ±5 degrees.

Are my current values acceptable?

Also, I have located the TDC (top dead center) using a dial indicator.

Thank you!

 

[mikidymac]

Yes, you are within the 5 degree.