I collect and work on old small engines. Mostly cast iron block engines. Most of these small engines use 5/16 x 18 bolts to fasten the cylinder head to the block. Sometimes these engines will have broken head bolts that always seem to break flush with the block surface so no grabbing them with Vice Grips to remove them. Taking the block tp have a machine shop to remove them is too costly. Years ago our good friend and mentor Okie Custer had a full set of drill guide bushing just for doing this kind of work. Our friend passed away in 2000 and all his stuff has hauled to the dump by his ^*#@& kid. The bushing I need has to have a outside diameter 21/64th and a inside diameter of appox 1/8 inch but that can very a little. I have search the web with no luck. The height should be at least a inch long, but a little longer would be ok. Our friends set had about 30 different size bushings. Somebody must still make them. I belong to 4 different small antique engine collector sites and other members need them also.
EvilDr235