Hitchcocks Forum

Hello All

Pre-unit 250 Clipper 1954. I’m rebuilding the engine. Crank & mains ok so that’s back together ok. Just fitted the timing cover, still ok, but when I fit and tighten the crank oil feed bolt into the new neoprene plug, it effectively ‘brakes’ the crank and prevents it turning. All was fine with the (very worn) cork seal before engine strip. If I back off the feed bolt by half a turn or so, the crank turns freely again.

Is this normal when fitting a new neoprene seal? I don’t remember the same problem when I rebuilt my Bullet a few years ago...

I’m tempted to fit a second sealing washer under the end of the bolt but I’m worried about that closing off the oil feed...

...or should I slice 1/2mm off the length of the neoprene seal? (It sticks out proud of the worm nut by about 3mm...)
Any thoughts?

Thanks

Stephen

The first neoprene seals supplied back in the mid/late ‘90s always seemed to be a cut to fit item.
I used to trim mine until there was enough seal protruding for the quill bolt to leave a polished concave finish across its width.

PS this was on a 500 Indian bullet, not a Clipper.

Have had similar with iron barrel, timing cover gasket was too thin gaskets vary in thickness dont take much to jam crank.

Thanks Ric, I took the timing cover off again this afternoon, trimmed about 1/2mm off the end of the neoprene seal and refitted the cover and quill bolt. Problem solved!

Thanks Scotty too, but the gasket was fine - the engine turned over with the timing cover on but stopped moving when I fitted the quill bolt so the gasket was not the problem.

Stephen