Date: Wed, 14 Sep 2005 19:39:01 -0700
Reply-To: Paul Dunham <paul@GIZMOWIZARD.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Paul Dunham <paul@GIZMOWIZARD.COM>
Subject: WBX oil pressure with/without cooler
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Hello Vanagonites:
This is my first post to this list.
I have a 1984 Westy that I've had for six years or so. It's great, I love
it, blah, blah, blah...
I suspected since I bought it, given the history told in the bag of
receipts that came with it, that the lower end of its stock 1.9 WBX was
probably well worn. It had been given a "top end" job at around 125k, and
it had around 140k on it. It ran strong and I drove it without incident,
but only for a few in-state camping trips with my family.
Last spring I put an oil pressure gauge on it (Volkscafe's excellent kit)
and confirmed my suspicions that the hot idle pressure was dangerously
low. Although the stock sender did not trip to light the idiot light, the
switch in the pressure sender did. So I rebuilt the engine last winter. I
found that the main and rod bearings were worn to a degree that
was nether alarming or surprising, but that the cam bearings were in
terrible shape. Five of the six shells were missing most or all of the top
layer of babbitt, and much of it was laying in the sump as flakes. I've
built a few dozen air cooled VW engines, and have never seen the like. I
suspect that the hydraulic valves are the big difference here, and they
often clattered when the engine was started after sitting a spell.
Anyway, the rebuild came out well, and now it runs like new. I still have
the oil gauge, of course, and am puzzled by range of pressures that I
see. Cold, it's over 50psi. The coolant warms up right away, but the oil
seems to warm up on its own schedule, and doesn't hit a steady state for
around ten minutes or so. I don't have an oil temperature gauge, but
assume an inverse relationship between oil pressure and oil
temperature. Anyway, cruising down the road and fully up to operating
temperature, the pressure is around 30psi, and at idle it drops to around
12psi. I gather that VW skipped the oil
cooler on the 1.9, but added one back on the
2.1 in '86. I have a question for anyone with a 2.1 and an oil pressure
gauge: What is your hot idle oil pressure? At 12psi, mine is double what
it was prior to the rebuild, and I'm not concerned about it, but I am curious
to know what the guys in Wolfsburg achieved with the water-fed oil cooler
they added in '86.
-Baffled in Bothell
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