I have a new in box 049 Tee Dee that will not come apart for inspection! I mean the glow plug, cylinder and back plate are so tight I can't move any of them!
 The engine has very good compression but I have not started the engine yet. I am using the wrench that came with it.
 I am not sure if using a little heat would help or not so I am wondering if there is a better way!

Thanks for your help, Richard K.

I've owned allot of new Cox TD's and I can say with all certainty you'd be better off leaving it together and just break it in using the instruction sheet from Cox. Especially if it's an earlier version without the wrench flats on the upper cylinder.


MM

Do you have the wrenches that come with engine?   If it is brand new and never been run, put it on a test stand or plane and start it.  Make sure it is at a rich setting.  May have to leave glow clip hooked up to keep it running if rich enough.  The plug should last through several runs.  after several runs start turning the needle in until it will run with out a battery.  Remember to keep it on the rich side.  Now to get the glow head off you will need the two wrenches.  One fits in the exhaust stack and the other for the head.  Make sure the one in the exhaust is inserted all the way.  Now put the muscle to it and the head should come loose.  Yes the head sometimes locks up and you will unscrew the cylinder if you don't have the right wrench for the cylinder.   If the exhaust wrench slips you may make a small burr in the exhaust opening.   Remove it before attempting to run the engine.  Wish you were close so I could do it for you.  Medallions are the same way.  I'm converting them over to the MECOA adapters on mine.

I have a new in box 049 Tee Dee that will not come apart for inspection! I mean the glow plug, cylinder and back plate are so tight I can't move any of them!
 The engine has very good compression but I have not started the engine yet. I am using the wrench that came with it.
 I am not sure if using a little heat would help or not so I am wondering if there is a better way!

Thanks for your help, Richard K.

    Why are you taking it apart? Just run it, that's what Cox engines were famous for, perfect out of the box and a remarkably high standard of quality.

     Brett

try to put some valve grinding compound on you phillips tip.....works really well to hold on

I have a TeeDee .049 that has not been apart since I got it in 1963, except to add a Galbraith head and Nelson plug around 1998. All else is original. Used in FF so not many total hours on it, but point is it runs and lasts a long time. I am in the "break it in and fly it" camp.

Reset tools are still available from Cox International. coxengines.ca

              The plumbers throw these out at work all the time. I disregarded them initially and one day it dawned on me. I have never had a cylinder I couldn't unscrew using it. I wrap the strap around the cylinder and pinch the excess in my handle hand to prevent it from slipping and off it comes. Here's a picture of the wrench https://www.grainger.com/product/SLOAN-Strap-Wrench-3EPX8 . As for the backplate, use the old Cox wrench which goes entirely around the glow plug. The others which are black that have the two spanner hooks are crap. You can lay the old wrench on it's side and it fits into the slots better than anything I have used.