Finding TDC

[Bobbie Martin]

Is there a way to locate TDC without removing a cyl head? I was thinking of some sort of piston stop through the injector or glow plug hole, but with precup heads I'm not sure.

[britannic]

You're thinking along the right lines, it may be harder to go through the glowplug port because of the angle to access the pre-cup outlet - removing an injector may be easier.

You'll need to determine when #1 piston is actually on the compression stroke; for this you can use the same trick as on the gassers, compress a rag into the #1 injector port, disable the engine from starting (disconnect the inj. pump pink wire) and bump the engine until the rag blows out.

Once you have the stop arranged so that it should contact the piston near the top of the bore, bar the engine over until the piston stops, mark the balancer (using a fixed point like a piece of piano wire fixed to a bolt or even the new timing pointer) and then reverse direction until it stops again and mark the balancer using the same fixed pointer as a reference. Divide the distance between the two marks and mark the balancer at that opint and you should have TDC or very close.