Tight Valves

[LEWISDR]

The valves on my 72 are all tight. Intake between 0.013 and 0.016. Exhaust between 0.016 and 0.017.

How dangerous is it to drive the car like this? My second question is, how can clearance become tight? I can understand how they might get loose through cam lobe wear etc, but can they become tight? Maybe the PO had set them too tight?

Yesterday was my first attempt at adjusting them but I was not successful. Next time will be better. I think I need to check the fit of my old shim adjusting tool and get some compressed air.

Dan
Vermont

[htchevyii]

It sounds like somebody set them a little tight to try and get a little more lift or less noise? It's common for the exh valves to stretch, the valve seats could also wear. Both would cause the valves to tighten up, but it seems unlikely in your case. I don't think you're going to hurt anything, Mark?

[ga.spyder]

I dont think that they are tight enough to worry with damaging anything.Mine(exhaust) were much tighter and no telling how long they were run that way.Do check the adjust tool carefully.Mine was off a fraction and I couldnt remove the shims at all.
Craig

[cooter131]

Did you measure them when the engine was cold?
Otherwise you might get wrong measurements.

Haynes manual provides the following values:

0.017-0.019 in INLET
0.019-0.021 in EXHAUST

Always when the engine is cold...


Just like Craig suggested they dot seem to be excessivelly tight.



George.

[LEWISDR]

Yes the motor was cold. Thanks for all the good advice everyone at least I can worry a bit less.

I feel like next time I go at adjusting them I will do better. Compressed air and maybe a bent little pointy thing will work for getting the shims out.

The car is off getting a very well deserved paint job and some rest while she waits until the end of the big freeze.

Dan
Vermont
72 1608 (it's orange!)