What should the camshaft endplay be for a 1956 312?  The manual shows .012, I have .032.
thanks

.032 is way too much.  I don't have the spec handy but .012 sounds big, like maybe an upper limit.
Most likely, your thrust plate is excessively worn.  Or the thrust washer is too thick.  That washer and plate determine the play.  Look for wear and measure the thickness of both.  Your clearance should be the same as the difference in thickness, assuming there is no wear.


Lawrenceville, GA

I target for 0.004”-0.006”.  Be sure that the washer without a key slot and has a chamfer on one side is on the camshaft snout behind the key with the chamfer facing the rear of the engine.  If turned backwards (chamfer forward facing), there will be an excess of camshaft end play.
  
By having a selection of both cam thrust plates and cam snout chamfered washers, I can usually find a pair that gives me the correct camshaft end play.  The difference in measurements between the two pieces will give me the ‘theoretical’ cam end play which eliminates having to put the pieces on the engine and perform a ‘real’ camshaft end play measurement.  If I don’t have the right combination then it’s a matter of machining one of the two pieces to get the desired end play.  If too much end play, then I simply take some material off of the chamfered washer that goes on first on the camshaft snout.  If too little, then I take some material off of the cam thrust plate.

Lorena, Texas (South of Waco)