<VV> cold valve adjustment :

BobHelt@aol.com BobHelt@aol.com
Tue, 17 Aug 2004 13:27:33 EDT


In a message dated 8/17/04 8:01:11 AM US Mountain Standard Time, 
philippe.esteve4@wanadoo.fr writes:

> 2-your easier method to find TDC
> 

Hi Philippe,
Don't know just who you were asking, so I'll give you my thoughts.

There are two TDCs. One at the top of the compression stroke and one at the 
top of the exhaust stroke. I assume that you are looking for the first one.

Now depending on the state of assembly of the engine, there are several ways. 
First, if the engine rear housing and pulley (or harmonic damper) are 
installed, you can put the notch on the pulley on the zero mark and be at one or the 
other of these TDCs. So you are halfway there. Now if the starter is 
connected, or if you have an assistant available to rotate the crankshaft (CCW) , put 
your finger over the #1 plug hole (assuming the heads are installed) and feel 
for the pressure to push your finger off. That will be the TDC for the #1 plug 
firing (the top of the compression stroke). If the distributor were correctly 
installed, you could have looked for the rotor to be pointing to the #1 
terminal instead.

If you are wanting to adjust the valves and dont know which TDC you are at, 
one way of doing this is to set the engine at whichever TDC comes up first.  
Then install pushrods and rockers, and adjust both valves for the #1 cylinder. 
(just the #1). Then rotate the crank a full rotation (360 deg). Inspect the 
rockers on the #1 cylinder. If both rockers are tight and feel to be properly 
adjusted, then you were at the correct TDC back when you adjusted them. But if 
either rocker is very loose and is free to move around, then you were NOT at the 
correct TDC back then, but you are now. So readjust the #1 rockers and 
proceed with the rest of the cyulinders according to the shop manual. BE SURE to 
move the pushrods in-and-out when looking for the zero lash point.  DO NOT rotate 
the pushrods because this may cause you to miss that zero point.
Regards,
Bob Helt