Technical Crankshaft Pilot bush

[jolly500]

Hi.

How 'tight' should the nose of the shaft be in the pilot bush? should it be snug or should there be some wriggle room?

Thanks
Steve

 

[the hobbler]

Personally, I think that there should be a small amount of 'wriggle' between the spigot shaft and the bush. If it is too 'snug', when the engine heats up and everything expands a bit, the spigot shaft risks being stuck in the bush. I always give it a liberall amount of lubricant and have it so that it is a smooth slde in-out, with no 'grabbing'.

 

[Toshi 975]

I had the engine out one day and decided that the spigot bush was a little worn. I needed the car back on the road ASAP so I removed the bush and refitted it the other way around and it was fine.

 

[Bleeding Knuckles]

Hi.

How 'tight' should the nose of the shaft be in the pilot bush? should it be snug or should there be some wriggle room?

Thanks
Steve

Hi Steve, During my last engine build I was advised by a 'Professional' engineer that if there is any wear in the bush it should be replaced, mainly due to the possibility of wear and tear issues down the input shaft
Ian.

 

[jolly500]

Thanks guys