Date: Mon, 11 Apr 1994 08:17:04 EDT
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: cchubb@ida.org (Chris Chubb)
Subject: Re: '66 bus w/ flickering oil light
>From: nick mcree <mcree@ccwf.cc.utexas.edu>
>To: Multiple recipients of list <vanagon@lenti.med.umn.edu>
>I was driving from Austin to San Antonio this morning, for the first
>extended trip on the new rebuild. It was cloudy and 75F. Humming along
>at 55mph, about 10 miles into the trip, and the oil light begins to
>flicker. I pull over, and let it cool. Plenty of oil. No bad noises.
>I decide to limp it back to Austin on the access road. The oil light
>stays out--unless the engine is at high rpms in third or fourth. I
>quickly figure to drive slowly, and the light stays out. Hmmm. Now
>she sits in my driveway, awaiting my attention.
>Question one-- I am concerned that I do not have an air-flow thermostat.
>When I rebuilt the engine there was *no* control assembly for the air
>flaps to remove. I did not consider putting one on. I have read the
>posts on where it should be, and what it looks like, and its important
>role in keeping the engine cool. This could be a likely culprit, huh?
A hot engine cutting the oil pressure is more of a problem at LOW RPMs.
When the engine is turning 2000, then the oil would have to be pretty
thin to loose pressure.
>
>Question two-- *If* this is indeed the problem, what is your opinion
>concerning removing the shroud and simply *scrapping* the whole air
>control flap assembly? Remember, I am currently in Texas--there is not
>much of a cold-start problem here.
If it is in, and working, leave it in. If it is not working,
jam it open and leave it in. It wont hinder airflow, and I have found
that it actually helps direct air to where it should go and it
'mixes up'the airflow to promote better heat transfer.
>
>Question three-- Apparently, the carb and timing settings are crucial in
>helping keep the engine cool. I would just about bet my ass that I have
>the carb and timing set properly. Just to make sure, though, let me tell
>you that I have the timing set at 7.5 BTDC, and it seems to run fine--no
>pinging, smooth acceleration. Your insight?
If the timing and/or carb are off, they would tend to overheat the engine.
But mostly at higher RPMs.
My prognosis: First, get the extra oil cooler out of the engine compartment.
If what I read was correct, then you had it bolted to the fanshroud inside the
engine. Bad idea. You are justrobbing Peter to pay Paul by heating the
air. Get it under the car, forward of the engine. I recently saw a nice
setup that had it bolted to the floorboards about even with the tranny.
It had a nive perforated metal sheet bolted over it for protection.
Second: When you put the engine back together, did you make sure that
the oil pickup tube was securely conneected to the oil pump inlet?
If it is not tight, you would be pulling air at high RPMs and causing
cavitation in your pump. Blows bubbles through the engine. Very Bad.
Also caused by a worn out pump. But mostly a loose/busted oil pickup.
You can take off the drain plate and check to see how loose it is.
If it is loose, you can try shoving it back in, wiggling it around.
Other than that, I dont know.
--- Chris Chubb (cchubb@ida.org)
__________________________________________________________________________
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\for Defense Analyses, the US Government, or anyone else. \
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