Date: Wed, 19 Feb 1997 12:56:44 -0800
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: bayer@sybase.com (David Bayer)
Subject: Re: 84 Westy Hydaulic Lifter problem
>| I'm confused by this - the sythetic (Amsoil?) caused increased lifter
>| noise AND seal leakage? I've heard of the leakage problem, but never
>| the increased lifter noise. My '88 saw immediate cure of lifter noise
>| upon switching to Mobil 1.
>| What's the explanation for the noise?
Well, I had switched to Mobil 1 about 1500 miles before the noise
reared its head. Before that oil change, it had been run on dyno oil for at
least 10k which the PO had not changed in over a year. In addition, I changed
the thermostat just before the excursion to the pass the day before the noise
started. I still do not know what the hell caused the noise for sure, but
this is my best guess.
The old dyno oil had been used well beyond its range and had been
depositing its waxes and the like through out my engine for quite some time.
When I switched over to Mobil 1, the syn oil started cleaning out the engine
but slowly. When I replaced the thermostat, the temp guage went from running
just at the edge of the white box to just above the red LED, so I believe
that is a significant change in operating temperature. So then I drove 90
miles through Seattle's winter storm up to the mountains where is was even
colder (there was no noise on this trip). Let the car sit til its cooled, and
then run it all hot again for another 90 miles til we return and pack up the
car. I am guessing that somewhere along this return trip a nice chunky bit of
wax blocked up one of the hydraulic lifters acting like a check valve in the
wrong direction. The next night when we start the car to head back to
California, there is a real racket that did not go away for over 5 minutes. I
added a little more oil because the oil looked low (didn't notice that the
driveway was on a decent slant though) which had no affect on the noise (due
to the fact that there had been enough oil already in the case and it was
about that this point where I realized the amount of slant to the driveway and
slapped my forehead a few times feeling stupid). So I ran inside, searched the
archives and decided to add the ATF. I drained the excess oil I had added plus
a little more to make room for the ATF. A couple minutes into the ATF
treatment, the noise (which had been decreasing a little) disappeared.
I changed the oil which was black as night even with the fresh oil and
the ATF. I think this supports the idea that the engine was really gunked
up. I have not had a single bout of lifter noise since then even when the
car sits for a few days...
dave
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