Hitchcocks Forum

I pulled the timing cover off a 1A Inter today to replace the gasket and I am a little concerned about the quill bolt bobbin, I can't remember but I thought they were a reasonably snug fit in the crank but this one didn't feel as tight as I would have expected. Anybody know how tight it should be and would it be a better idea to go back to a quill bolt?

I do know folk who've returned to the original quill bolt, not being happy with the fit of the new "dog bone" type. The original is maybe a bit more tolerant of poor concentricity between the crank and the outer cover. REgards, Mark

From my recollection, when I had a Constellation many years ago, the received wisdom was that the self-aligning properties of the 'dog's bone' quill made up for non-concentricity of the crank with the quill hole in the timing cover. I read somewhere (probably at Hitchcock's) that the sides of the original quill would wear if not concentric with the crank and thereby reduce oil pressure. It certainly persuaded me to buy a 'dog's bone' at the time!

In principal the dog bone bobbin is a good idea but in this case I'm not happy with how loose it is in the worm drive

Norm,is it possible to measure any movement in the worm,it may be spinning off centre and
therefore causing wear to occur.As has been said the bobbin will take care of a non
concentric situation but won't handle any up and down movement for long
cheers
colin

Bit late Colin, Charles has taken it back home but I'm going to have to get him to bring it back, I should be able to check it with the dial indicator