Re: Valve adjustment in early MODEL A

Posted by David Dewey on September 12, 1998 at 11:06:50

In Reply to: Valve adjustment in early MODEL A
posted by Eduardo on September 11, 1998 at 15:45:01

Eduardo,
The '28-'31 Model A does not originally have adjustable valve lifters. To adjust the valve, you have to remove it from the block and grind the end of the stem. This isn't as difficult as it sounds, one can make a fixture for a bench grinder to hold the valve and get a prefect surface. Actually, I prefer to grind with just a littl concave area in the center, as I believe it will act like an oil cushion to soften the original point of impact. Unproven theory, yes, but the engine's still running!
It is a time-consumng process, and shops that do this regularly have a way of measuring just how much they are taking off, and can sometimes get it 'right' with one try.
BTW, hammering on the valve will just bend it, and probably put a flat spot on the cam (cams are not as hard as most people think!).
-David D.