Yes, I agree, John. I enjoy it when I am able to fix another's problem and put the engine back to good use. 6 years ago, I got a used Enya .19-VI TV for a bargain. However, when I received it, had a bent prop shaft. The prop wobbled when mounted. It was also missing the prop nut and washer, found one that fit in my motorcycle salvage parts bin and a fender washer in my hardware bin. Drilled / reamed the washer to proper shaft size. Took my plastic faced beater hammer, gave the prop shaft a couple sharp whacks while rotating the crankshaft, until I had no perceptive runout.
Lo and behold, I was able to straighten it, put a 9x4 prop on it on the test bench, bingo! Ran without a hitch even to full throttle. Engine has like new compression. Be a good engine on my Robin Hood 25.
Chuck, sorry to hear about your Fox .35 Rocket grenading on you. Stuff sometimes happens.
I read recently of a man who cowled his OS Max .30 Wankel on a scale cabin job after successful use on an Ugly Stick. Cowl had insufficient cooling holes. Engine runs hot, OS warns about adequate cooling, cowling should have twice the exit ventilation as entry. Turned an expensive engine into a paper weight after a couple flights. Seriously overheated, it lost compression, no doubt ruined the fine fitting machined rotor. (Has no rotor side seals, only apex tip seals. At least he didn't bite the big one like the R/C turbine engine guys; one Figure-9'd his $30,000 twin engine with a realistic fireball ending.)
Also interesting according to article on Sceptre Flite, Peter Chinn's write up, the earlier versions prior to the PII has a precision ground Meehanite rotor (just like our iron piston steel sleeve engines) and steel chamber parts. Those, it was recommended to run 25% Castor oil fuel and mild nitro (just like our earlier engines, too).
Would love to have a Wankel, but they were close to $500 new. Now on the 'bay, they are commanding ultra ridiculous prices, new close to $1K. My stash of K&B's, Enya's, HB, Fuji, OS, Cox, OK, Thunder Tiger, Magnum, Sanye, Norvel, Fox, Gilbert, Testor's Red, Blue, Black (Series 21) and plain (old man McCoy's pre-Testor) engines didn't cost near that at all.
Speaking of checking an engine's internals prior to running like your Fox .35 Rocket, Chuck, back in the mid 1980's, I bought 2 Fuji .099S-III R/C engines on closeout from Hobby Shack for only $10 each new. I took them home, removed the back plate. They were full of metallic swarf. I further disassembled them, and flushed the crankcase and parts with solvent, before reassembling them. If I ran them as-is, it would have ruined them. Something happened to the Fuji factory in Japan before they folded. Guess they were so pressed on putting out engines, they were just machining and assembling without cleaning.
First time I posted about an engine I rescued 4 years ago, but since I originated the thread and this engine was also a Stallion, thought I'd save some server disk space and continue the thread post Covid.
Also got another Stallion, this time an R/C one. It seems to be a low mileage one also, but missing the exhaust baffle for mufflerless good idle. Next will be to run a bench test of these two I repaired. Also got another Testor .35 Red Head I picked up off the 'bay for under $30 shipping included. Will post about it in another thread. Also picked up a Testor .35 Blue Head R/C during Covid.