Hitchcocks Forum

So I changed the oil and filter on the Bullet today and, after checking that I had a spare gasket, thought I'd check the oil pump worm. Everything was fine so I reassembled with the new gasket only to find the engine was locked. After a bit of a think I realised the culprit must be the new gasket. The new one was 0.5mm thick. On checking the remains of the old one I find it was 0.8mm thick. That 0.3mm was enough to bind something in the timing chest as when I eased the screws a tad the engine turned over fine.
Order in for new gaskets - hope Mr H is as quick as usual.

Just noticed there are shims on camshafts and should be added "as required"
However, I only have one 0.005 shim on each camshaft so I don't want to remove that as I suspect it acts as a thrust washer.
Must measure the replacement gasket carefully to get back to where I was.

Nothing new about that problem pETER

New to me Norm, I must just have been lucky before.
Anyway, new gasket of correct thickness fitted (v. fast delivery from Mr H as usual) and all is well.
I suppose I should really add .005 shims until it binds up again then remove one.

Interesting Pete thanks for posting, will check more carefully in future as well..

Often wondered about the gearbox inner gasket as well but maybe not as critical..

Can you remember where the 0.5mm gasket came from or are they all like it from Mr H now?

Just trying to understand did you order two gaskets at 0.5mm or your second purchase was the correct 0.8mm

I suppose regarding the shims any undue noise due to sloppiness would have to be addressed with shims but a little tight would be worse... Cheers gwilly.

The timing gears are straight cut so there is no thrust to worry about. You can add and remove shims with relative impunity.

Buckets of sprag shims kicking around out there, that is all I use

Gwilly,The thin gasket was one I had in a box of stuff someone gave me. Certainly the right pattern so I never thought of the thickness. The new one was 1.0mm, as was the one I took off. They squash down to 0.8mm in use.

Reassuring pete thanks.

Just don't get caught using an Electra gasket, only way to tell in one oil hole is moved slightly but you really have to check