The three groove keepers are designed to be loose enough so the valves
rotate. That is also why the rockers screws hit them off center.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Zoltan
Sent: Tuesday, May 26, 2009 11:04 AM
To: vanagon@GERRY.VANAGON.COM
Subject: AMC valves, Boston Bob

One important fact I learned from Bob, was that the AMC heads have loose
keepers.  The two halves meet each other to touch, thus grabbing the valve
stem, being loose, they travel up and down until they break through the
grooves and the valve free to move deeper inside and then operated by the
piston to have it pushed up.
So, the first thing I recomment to anyone I meet is to have the keepers
ground at their sides until they don't touch each other.
Bob was very happy with the AMC heads and tossed the old ones for their
metal fatigue.  In his experience, it was not worth chancing all the
troubles by putting the old ones back.
He liked the better material the AMC heads are made of.
So, the keepers must be fixed first.
Zoltan