Top Dead Centre

[Michael L.]

Good Morning Everyone:

I have a '41 Continental with a V-12 engine and I was wondering if anyone has devised a fool proof method of locating top dead centre without pulling the head. My reason for asking is that I want to put an index on the front balancer so I can time the engine accurately without using a distributor machine. I don't know why Henry didn't do that.

Anyone have any thoughts on the subject?

Thanks,

Mike L.

[peecher]

Mike, Using the front damper for an index is probably not a good Idea as the outer "halves" of the damper can actually move/rotate about the pulley mount. The fan however is mounted directly. If done carefully Henry's "manual" method of setting the timing can be pretty acurate. Excess wear on the drive key can make a small difference on the initial timing tho.

[hchris]

Have you considered using a vacuum guage to set timing rather than a timing light; the reason I ask is that I consider this a far more effective way of tuning the engine. The relevance of timing marks has been lost somewhat due to the burn characteristics of modern fuels, in addition as engines age so do the distributor/valve drive mechanisms which introduce variations in timing.

Most standard engines will perform best with a steady idle vac reading of 18 - 20 inches; you only need a fitting plugged into the inlet manifold to hook up a vac guage and then move the distrubutor around until you get a smooth steady idle at these numbers.

[Michael L.]

Thanks for the comments Peecher and hchris. I was thinking that the index marks could be on the back half of the damper which is keyed to the crankshaft and therefor can't move. The index marks could then also be used to syncronize the distributor and also to check the vacuum brake and advance functions of the distributor.

But the question still remains; how to find TDC accurately?

Mike L.