Date:         Sat, 27 Oct 2018 18:56:58 -0400
Reply-To:     dbeierl <dbeierl@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         dbeierl <dbeierl@GMAIL.COM>
Subject:      Re: The value of instrumentation
Comments: To: neil n <musomuso@gmail.com>
In-Reply-To:  <CAB2RwfiXoL6qb00ZFLmyxTirkg=fB7tv6_VB4CR4ierZfDFWNg@mail.gmail.com>
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>
> I have no idea how worn the lifters are. If
> the lifters are quite worn and bleed down faster than normal, I wonder
> if that causes the heads' oiling circuit(s) to lose its' prime. i.e.
> what would an oil gauge on a spare port where the "high" pressure oil
> switch is show after engine sat unused 4 or 5 days?


I wouldn't think lifters would wear much internally, since the piston
basically only moves at starting time and then only if it was under an open
valve.  But because of the extraordinarily small clearance between piston
and bore they're subject to getting sticky.  The restoring force from 60
psi of oil pressure is a lot less than you'd think given the small piston
area.  When one does bleed down all it does is allow the valve to close and
ooze ?half a cc? of oil out the end.

Can't speak to the rest except to say I'm used to thinking of "prime" as an
issue in suction systems rather than pressure one.

Yrs,
d