Medallion R/C .15 and friend

Bob- I've never put a medallion in the antifreeze/crockpot. I do know they ( plastic carb bodies) tend to change color or turn whiteish
https://www.coxengineforum.com/t9484-carb-body-cleaning-plastic#120581
To disassemble before the AF boil,  try warming it in the oven or with a hair dryer to soften up the old baked on castor. If yore gonna run/fly it, clean it up with old fuel or rubbing alcohol. If you're making a display engine the replacement carb bodies aren't cheep, but they're not outrageously  expensive either.  Congrats on the flea market find!

Thanks, It's pretty beat but I think it will clean up.

I'm just going to run it.  I have a couple of .15 sized models that are just begging for power.  I think I have a couple of .15 sized wrenches left over from previous engines.  Gonna need the spanner to remove the prop drive assembly.  

The strap-on module is huge, to bad I don't have anything to use it on.  It's cracked any way and a little out of plumb.  I love those little .20 sized OS's, it won't be difficult to find a use for it.  

Bob

I cleaned up the flea stuff this morning. Found a nice little Williams tank in the module.



Removed the needle on the .15, everything else is stuck solid.



Throwing caution to the wind I dumped the whole thing in the pot. But I did not bring it to a boil, I cut it off when a little steam occurred. About three hours.





I got the cylinder off but the back plate would not budge, had to apply the old heat wrench to remove it.



Then the throttle sleeve would not come off and the heat gun was no help. I put it back in the pot this time bringing it to a boil and it slid right off. Everything cleaned up with a little 0000 steel wool and a soft tooth brush on the plastic and aluminum parts.



Got it back together and lookin’ good.



But......this is strange, the cylinder to case gasket expanded, or the engine shrunk. Now the gasket is to large to use, it hangs out over the edge and it’s metal....But there is tons of compression in this engine. Also I forgot to note how the piston came out. The COX print on the con rod faces out right?

Bob, I'm a fan of the piston pin vs the ball socket. Yes, the words face out on the con rod. In addition, the base gasket was probably used due to the piston coming too close to the landing of the glow plug. I have used head gaskets from different engines to jack the cylinder up if needed. Cox would suggest to cut a paper clip the same width of the landing and lay it across the cylinder. Turn the engine over and see if the piston pushes the paper clip wire up and off the landing. If so, shim the cylinder as needed. Neat engines, very loud in the control line version, they don't make a lot of power as some would claim. They're just a decent light little engine.

Thanks Ken, I will try that paper clip trick.

But I think I will tape that case gasket down to a piece of wood and use a dremel cutoff disc to cut out a small portion then pinch it with my fingers and screw on the cylinder. May work. I have no idea how it expanded, it seemed to fit correctly when I removed it.

BTW, the case pressure nipple was never drilled through and the glow plug is good.

Bob

All the base gaskets I have for these protrude slightly and are not tight fits.

Looking at the "before" pictures I think that the gasket size was masked by the goo.

Another nice engine clean up.