Engine Stripdown

[Swiss Tony]

I managed to strip the block down with the exception of the water pump and Jackshaft(?)

The pistons at each end have what appears to be little gouges where the valves have hit.  In cylinders 1 and 8 there are 2 dents, in cylinders 3 and 6 there is just one, and the others are clear.

Having been frustrated by the engine that came out which was just a solid lump of rubbish, I was heartened with the progress I made,

[Swiss Tony]

2 more pictures

[Richard B]

Thats a MkI head, the MkII is blended out by the inlet valve.

Are you sure that the valves have hit the pistons, as usuall they are bent. MarkDeTriumph post some years back when his chains cut loose.

IIRC some pistons have machined marks to give clearance to the valves (possibly when they are closed)?

[JohnD]

The two marked pistons look to have different marks, so porb not machined to clear the valves.
Do you know what had bene done to the engine?   Skimmed to raise CR?  Certain of cam timing?  Hi-lift cam?

There is a cheap way to relieve the valves.
Cut notches on the edge of an old valve, fit it into head and head to block.
With piston at TDC
Engage valve stem in drill chuck, spin valve and lower until it contacts the piston.
How far you push down on it is up to you!

John

[Richard B]

Take the cam off and see the way the valves protrude below the head face.

If the head has been skimmed then the valves would touch the pistons even when they are closed. With the valves at an angle it's a close run thing.

Thats why you can get thicker head gaskets from Paddocks / Rimmers etc and why Tony Hart sells "Head saver" steel gasket shims form Stag heads.


I would say take your heads to Tony Hart as he runs a reconditioning service (via eBay) or another Stag specialist such as EJ Ward.