[Amc-list] new lifters old cam

["Swygert, Francis G MSgt 436 CES/CECM" <Francis.Swygert3@xxxxxxxxxxxx>]

"And lastly hydraulic flat tappet lifters are BUGGY WHIPS ! No modern
engine in production uses flat tappets any more. All new engines
currently made are Over Head cam or roller lifter."
------------

Only one problem with this statement Larry -- most OHC engines use flat
followers. The cam acts directly on a "lifter" (flat cap) directly on
top of the valve in many cases (like my motorcycle -- 1980 vintage, but
many new ones are the same) or on a flat machined surface on the
"follower" in others (like the Ford 2.3L -- a follower is an arm between
the valve top and a "lifter" or lash adjuster off to the side, also in
the head - the cam rides on top of the follower between the valve and
adjuster -- not necessarily for you Larry, but some may not know!). I
know some recent Hondas work that way. 

A shaft and cylindrical roller could be made into a follower or valve
cap. That would raise the height of the valve cover a bit, but would
work. I haven't seen any done that way, but I haven't cracked open
anything newer than a 93 Nissan Sentra and 96 Ford 2.3L either. So I
would think most OHC engines would also be affected by the lack of zinc.
I'm sure the manufacturers will come up with a replacement additive --
eventually. I think the lower quality metals used for cheap lifters is
more of a problem. 

I checked the MSDS sheets of AMSOIL. Their heavy-duty diesel oil
contains zinc (CERCLA 40 CFR 302.4...Zinc and Compounds @ 1.48-2.63% RQ
1 lb), their High Performance 10W40 contains the same amount. Their
regular 5W40 has it also (1.62-2.50%, RQ 1 lb). Their regular diesel oil
has the LOWEST possible amount (1.30-2.58%, RQ 1 lb). So basically all
their synthetics have roughly the same amount of zinc. Zinc is the ONLY
additive listed other than the synthetic base! This doesn't sound real
good. I was thinking that maybe synthetics would have better wear
resistance, but if AMSOIL thinks it's worth adding to their full
synthetic base... Maybe a synthetic additive can be formulated, but it
ain't there now! 
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