Adjustments on Adjustable Valve-Train for my 390???

[Rick Young]

dwisdom

I haven't read that you have solved your problem. After reading about it, I decided to see if the noise in my 390 was anything like what you described.

I found that I do have out of spec. valve adjustment, by checking the tapet clearance. I have hydrolic lifters and no adjusters.

My book says check the valve lash with the lifters blead down. I have a '64 engine and my book says that I should have .050" to .150" clearance. I found that several were in excess of the upper limit.

I found that it was difficult to compress the lifters, especially working alone. I assume that I have a good bleed-down rate because I had to hold pressure on the lifter for about 30 to 45 seconds to get it fully compressed, and then check the lash. If I let the pressure off the lifter it immediately filled and took the whole effort to get it re-comressed.

It is possible that by setting zero lash that you are still in excess of the required adjustment. The lifter will have more movement than the specified clearance of .050" to .150" and give a false 'zero' setting. My book also lists different ranges of clearance for different years of the 390.

I have some new .060" over length push rods ordered that should bring my lash back into the specified range and hope that will stop my valve noise.

How has your problem worked out?