2001 gtx 787 RFI Top end rebuild

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I split the case and there was tons of brass and aluminum filings there. I assume a piece of the pto piston broke off and got in there to destroy the rotary valve gear. I ended up vacuuming out the upper and lower halves. Rinsed with gasoline. And put it back together.

I'll reinstall next weekend. Hopefully it will fire right up
Hmmmm.... I don't think the piston can get into the chamber. On the one I repaired the gear failure was a lubrication issue. Good luck with it !!
This SOB kicked my butt for a lot o hours. This is the RFI running with a destroyed brass gear on the rotary valve. It definitely teased me and confused me as it would run like this. Now I know a WHOLE LOT about Sneaky Rotary Valves. LOL :D Don't judge me.... after I opened up the Rotary Valve and reset the timing in the dark I spent a lot of time trying to diagnose this problem. Live and learn. :D :D

So yours was running like that with a bad .rotary valve gear? At least mine would just sputter and die. But it wore me out as well. The only thing I can think of causing the brass gear failing is perhaps If not a piece of piston then it may have been from one the the sleeves that cracked.

I have the engine all back together. I am planning on reinstalling this weekend. Hopefully it will run.
That was about the 15th time I tried to start it and one of the few times it kept running. If ever your engine blows oil back through the intake that's a good place to start. LOL :D
Thanks for the heads up. I hadn't considered that. I'll drain the tank and clean out the lines before I reinstall.

Also you got me wondering about how I thought that a piece of piston could have gotten inside. I went back and looked at the old cylinder sleeve on the PTO side that lost compression. It looks like a piece of the skirt on the sleeve chipped off. Perhaps that caused the whole failure.
Nothing can get inside the rotary gear reservoir. It is sealed from the rest of the engine.