At 01:19 PM 3/7/99 -0800, ken pletcher wrote:
>My 69 2000 has a B-cam and 2 lobes are begining to wear. I just bought new
>rockers and B-cam and here is the problem. It sounds like one valve is
>adjusted to loose,I have them all adjusted very snug at 0.20 intake and
>0.30 exhaust when hot.
Ken, I hope you're talking millimeters! Valve lash should be .008" intake
and .012" exhaust hot, which is .20mm and .30mm.
On that noise, can you locate which valve it is? If you have an automotive
stethoscope, that's the easiest way to locate it. If you don't, you can
fake it with a long socket extension. Put one end against the bone next to
your ear and the other end against the cam cover (hope your engine doesn't
rock too much!).
If this noise is occurring with the new cam and rockers installed, you
should probably check to make sure that the cam lobe isn't running off the
end of the face on the rocker. Locate the rocker that is suspect, clean it
thoroughly, put some machinist's dye on it and turn the engine over by
hand. Then check the pattern in the dye.
>My other cam did not have this problem,one thing I
>did notice is that the old rocker arms have B marked in each and my new ones
>don't. Are there different rockers for the B-cam?
There were differences in rocker arms, but it didn't correlate to the cam
grind. Early rockers were a one-piece design but it turned out that the
rubbing face that contacts the cam wasn't hard enough. So a two-piece
design was introduced that used a harder insert for the cam face. Other
than that, the two are the same. I have rocker arms with C, E H, I, O and
nothing, and there appears to be no difference at all between them.
Gordon Glasgow
Renton, WA
http://www.gordon-glasgow.org
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