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Re: [T2] Oil cooler lines



I think in my situation I'm not too worried about loosing some pressure,
I'm thinking less might be better with the situation as it stands now.
I've included my reply to Michael Benthin's recent post directly to me
below.

I've had the oil bypass spring and plunger out of the engine. I polished
the plunger with very fine crocus cloth and measured the spring against
the spring from a spare engine (length not tension) I visually compared
the two plungers and they are exactly the same. The plunger will gravity
drop from the bypass port with the engine cold.
Several individuals have stated that 50 psi at operating temperature is
about the best that they hope for when they rebuild an engine and I've
been told that the bypass valve should open at 37-42 PSI and bypass the
cooler and filter. In addition I've heard that anything over 40 psi at
operating temperature is rare. 
The only exception to the standard rebuild practice was the installation
of new Porsche oil pump gears in the old VW housing. This type VW oil
pump is particularly hard to find at less than $375.00 new and I had to
return three pumps that were the wrong pump before I sought the Porsche
source for new pump gears.
The crank spun freely on assembly lube and the rods dropped slowly with
the assembly lube so I don't see TOO tight on the bearings. The crank end
play is at about .008. The crank is standard as are the rod journals.
I get the same high readings on oil pressure with a manual gauge about
ten inches from the oil sender port so I'm thinking the electronic gauge
is correct.
I've rebuilt about four type 4 engines and have never had these high oil
pressures on the other engines.
Maybe I'm just bitching about having built a really tight good engine, my
concern is the potential of blowing an oil cooler or exploding a filter
at highway speeds if the bypass valve just sits there and flutters
causing a shock effect.
I'm going to install the manual gauge at the oil cooler when I install
the cooler and it should tell the tale of exactly when the bypass valve
is opening and neutralizing.
I try to be honest and straight when describing a situation or problem
and I've presented this scenario exactly as it is without embellishment
or fudging on any of the numbers, it has indeed caused some speculation
of whether I am full of crap or exaggerating the numbers. If I make an
error in reporting or prescribing I admit it immediately so bad
information doesn't get into the archives and screw up someone elses
brain.
As for your engine...... just run it as long as it doesn't smoke or
rattle. The chances of it failing all at once with a blown piston or spun
bearing are pretty slim.

Stan Wilder

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