Listees,
On the newly rebuilt '68 vintage engine I recently installed in my '65 I
replaced the early solid lifters with the later type bucket lifters and
new Crane push rods along with installing a reground stock cam.
I set the lash to .013 as specified for the later engines, and I get a
light, resonant valve clatter at 3500-3600 rpm, just a brief but
noticable noise as I pass though this range, and it will stay if I hold
this rpm. It is not the rocker arms hitting the valve stem, it is
internal. I opened up the lash to .015 (early spec) and it gets louder
over a broader range.
Are these bucket lifters flying up off the top of the cam lobe and
hitting the back side? Should I tighten the lash to .012 or .010? I
have dual springs on a completely rebuilt stock head (silicone bronze
guides, stellite exhaust valves, hardened seats), so a spring problem
seems unlikely. Engine runs great.
This is a new one on me, any ideas?
--
Stuart MacMillan
Seattle
'84 Vanagon Westfalia
'65 MGB (Driven since 1969)
'74 MGB GT (Restoring)
Assisting on Restoration:
'72 MGB GT (Daughter's)
'64 MGB (Son's)
Parts cars:
'68 & '73 MGB, '67 MGB GT
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