Oil-overflow in new 717 engine

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Hi, had to replace my engine, with an fabric new. Runned it for one hour, this spring took it out, hardly goes round, took out the spark plugs and cascade of oil sprayed out of the engine.

Anyone got a clue of what happened? And how to fix it?
Thanks for your answer. Oups, really? Hope not. Could it be on an new engine? Is there any chance it can be some kind of leak in the part who mix in oil in the fuel? Do you know how it works? I can not the system at all :)
No it's not the new engine and there is only a .000000009% chance it could be the oil pump.

The oil tank feeds the oil pump but also a cavity in the middle of the engine that lubricates the rotary shaft that drives the rotary valve off the crankshaft. This cavity is always full from the oil tank and has 2 crank seals and 1 rotary shaft seal into the intake so that is where 99.99999999% of oil leaks come from that give the symptoms you have.
Pull the rotary valve cover off and see if there is any oil leaking out from the case halves. Leave the cover off for a day or two and see if there is any oil somehow leaking out of the injection lines. The rotary valve shaft seal might be leaking, did it get replaced when the motor was worked on?

Those are the areas that might explain oil in both cylinders.
i picked up two 96' GTI's and starting flushing the fuel tank, lines and such. took out the oil tank, cleaned and added fresh synthetic that meets seadoo specs. Rebuilt the carbs. Put everything back together. Cranked it over and it locked on oil on top of the pistons. took out the plugs, cranked for about 10 seconds on and off about 30 seconds and kept checking the starter to be sure it was not getting hot. after a couple hours and again for a bit the next day it is still flooding with oil. I did notice oil on the butterfly s of the carbs. Makes me thing the rotary shaft oil seal is bad since it just keeps on filling with oil. Anyone know if i can pull the shaft and replace the seal without pulling the engine. These skies are real low hours and have good compression.
ski number two is good, no oil leak to speak of, just blew lots of smoke on the first start. ran for about 15 seconds. will connect the water hose and run more before i hit the lake.
these skis sat for about 2 years on the trailer, with the trailer tilted up at about a 45 degree angle.
You can cheat and put a valve in the oil line that feeds the rotary valve. If the leak isn't horrible bad you shouldn't have any problems.

I found this leak on an engine I had apart. Had a bent rotary valve but this issue is the builder didn't put enough sealant on the partings. I found the leak by pressure testing the rotary valve chamber with about 5 -7 psi. Pinch off one of the hoses and put the gauge/testor on the other. DO NOT OVERPRESSURE. Good Luck.
What lead me to test this was I saw a valve on the oil feed line. That is usually a dead giveaway that oil is getting into the combustion chamber.

RFI Rotary Valve leak.jpg
thanks for the help.
can i pull the rotary valve shaft and replace the seal behind the spline without pulling the engine out of the ski, or does the whole thing have to be disassembled to get the shaft out to replace the rotary shaft seal behind the spline.
I don't know if that is possible or how much of a pain it would be. Some hulls may be easier than others. I have not seen a leaking rotary valve shaft, for me it has been the crank seals which means replacing the crank shaft. Good Luck.
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