Newbie question on engine differences throughout production

[Chancer]

Gearbox first motion shaft passes through the clutch centre plate and is then supported by the clutch spigot bearing AKA pilot bearing which is a transition fit in the rear of the crankshaft so the flywheel doesnt come into the equation.

I have come across many running vehicles that didnt have the spigot bearing fitted, some even came from the factory like that, without it the clutch centre plate can run eccentric and the input shaft bearing will quickly fail as the shaft should be supported by a bearing at each end.

Sometimes when doing a clutch change and the gearbox goes back in far too easily I ask myself did I actually check to see that a spigot bearing was present, if I cant recall out it comes again to check.

[rgh0]

The nose of the input shaft fits into the bearing mounted in the rear of the crank for the 4 speed boxes. The Lotus five speed box had the bearing mounted in a carrier fitted into the centre of the flywheel. I would normally replace the oilite bearing with a needle roller and make up a bush if needed to fit it to an early crank.

cheers
Rohan

[RogerFrench]

Re: Cylinder heads. There were Weber heads, Stromberg heads and Big Valve heads. There were Stromberg Big Valve heads too, but for US Federal cars. These heads are not high compression like the Weber / Dellorto Big Valve heads.