[Amc-list] Noisy after rebuild

["Bruce Hevner" <scramblr@xxxxxxxxxxx>]

What many folks fail to check on a rebuild is "dry lash" of hydraulic
lifters. Yes hyd lifters have a lash spec too!
 This is most easily checked before completely assembling the engine and
the lifters are "dry" (not yet pumped full of oil). 
I used to do a LOT of Mitsu 2.6 engines for a customer of mine. They are
an OHC with a hyd lash adjuster in the rocker arm. The lash spec is
.020-.060. What I found was that the engines with .020 had no lifter noise
on a cold start up. As the lash got closer to the .060 mark the engines
started having "valve clatter" on a cold startup till the lifters pumped
up. 
 What happens is when the cam is stopped with a lifter on the "nose" (and
under spring load) the lifter is bled down over night and then ticks in
the morning till the oil pressure pumps it back up. .020 lash is not
enough to make much noise but .060 IS!
 All engines with hyd lifters have a dry lash spec but it is often hard to
find. If your engine has excessive "dry lash" for whatever reasons it is
susceptible to lifter noise on a cold start.
 Another reason would be poor "anti-drain back valve" in the filter IF it
has one (not all engines do). Try different brands of oil filters and see
if it helps.
Just some suggestions,,,
Bruce Hevner

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