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Post  balogh on Mon Feb 03, 2020 7:36 am

Some of you may have applied this method, I just improvised it on an old reedy, and I hope others will make use of it.

My older 049 reedies do not have flats machined in their top cylinder fins for the wrench, so unless you are lucky to remove the cylinder by heating, drenching the engine in fuel, or applying a leather belt removal tool etc., the last resort is to push the wrench fork into the exhaust ports and twist it, that I try to avoid as much as possible for fears of cylinder damage.

But if you are still wound up with a stuck cylinder, and if the piston needs e.g. ball-joint setting,  you cannot remove it from the crankcase together with the cylinder.

I noted though, that thanks to the engine dimensions, if you strip the engine of its back plate and glow head, then the piston can be removed with the cylinder staying in place, through the steps below:

1. Remove engine tank or back-plate and glow head, together with head shims.
2. Turn crankshaft to push piston up to top-dead-center
3. With a forceps, unhook the rod end from the crank-pin.
4. Push piston out from cylinder through its top. Put e.g. a blunt wooden or plastic stick into the rod lower end then push piston up through the cylinder. Avoid using any metal rods for this in order not to accidentally scratch the cylinder wall.
5. Set the piston ball-joint end-play as required...do  not tap it too tight, some very small ball-joint play is needed not just to allow the varnish build-up in the ball-joint cup, but to allow the slipping of the rod-end back on the crank-pin too
6. Do the steps above in a reverse order 4 through 1  to assemble the engine again

Unless you have a tapered bore No 4 or No 5 cylinder- that comes mainly with old 049/051 Tee Dee-s and maybe the Venom -, the process enables the removal of the piston without the  forced removal of a cylinder stuck in the crankcase.

Tapered bore cylinder/piston combos on engines having less than hundreds of hours on their clock, though,  will not release the piston by pushing it through the cylinder.

Good luck applying the process.
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Post  fredvon4 on Mon Feb 03, 2020 8:53 am

Dang I keep carping about this!!!

The Cox wrench DOES NOT EVER EVER EVER GET INSERTED INTO THE EXHAUST PORTS....EVER!

Sorry Balogh...I know I am yelling and being rude....I was an Army instructor.....a pure OCD certifiable basket case loud profane out of control when I see; 1- wrong tool used, and/or 2- correct tool used improperly


The Cox wrench end fork opening fits ACROSS THE EXHAUST PORTS...fitted ACROSS -----the wrench is twisting on the OUTSIDE of the front and rear port opening

it can not deform the port inside raising the burr everybody seems to need to remove
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Post  balogh on Mon Feb 03, 2020 8:58 am

Thanks Fred, I of course did not mean to tuck the fork into the exhaust ports, (and I do hope nobody would have reasonably thought my intention was such)  but to slip the 2 forks over the ports as originally intended...but I avoid using the wrench even in this correct, intended way as it burrs the external edge of the ports..sorry for my Hunglish Very Happy

You do not have to apologize about you having been an army instructor...back in the army where I was just an enlisted nerd, once an officer asked me what the standard items in a military side-bag - carrying the gas mask and others - included, and i said: a white flag...needless to say it was not the right answer expected and that real OCD really exploded in curses...
Otherwise what is your opinion about the core idea in my post?
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