Date:         Tue, 19 Mar 1996 22:32:03 -0700
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         rickgo@halcyon.com (Rick Gordon)
Subject:      Re: Overheating symptoms?

>
>You don't.  Get some gauges.  Start with oil pressure.  Don't drive your
>bus hard if the pressure drops below 25 psi under load.  It's probably
>overheated at that point (or has some other problem like worn bearings).
>Next get an oil temperature gauge.  Don't drive your bus hard if the
>temperature goes over 230 degrees F.  Don't trust the reading if your
>engine isn't turning over very fast (like under 3500 RPM).  It may be
>artificially low depending on where you mount your sender.  Next get a
>cylinder head temperature gauge.  Preferably two - one for each head.
>Don't get the kind that mounts at the spark plug if you have a 72-83 air
>cooled bus - it won't fit.  Be concerned if the temp reaches 350 degrees
>F.  You will notice the temp stays down when the engine is turning fast
>(like above 3500 rpm).  Rules of thumb:
>

I'm going to argue these numbers a little bit - my opinion only, nothing
personal. The advice is sound though - you'll learn a lot more about the
engine
under load with gauges installed.

With these stats you'll never get over any mtn passes, at least not in the
summer. The heads are going to get hotter than 350F, hell that's their
normal operating temperature! If you're climbing a mtn with it, start
worrying over 550F. Oil temperature can arguably get hotter - water doesn't
boil out until 210F. Oil pressure will get lower as the oil temp rises.
Also the head temp sender *will* mount in the spark plug hole in a 1980
engine, and its pretty much the same as the 78-83. The head temp gauges are
kind of pricey - if you only get one, put it on #3 cylinder.

>DON'T LUG THE ENGINE UNDER LOAD - take hills in lower gears at high RPM
>DON'T FLOOR IT - except for brief periods.  Use 3/4 throttle and downshift.
>LISTEN FOR PINGING - if you hear ANY at all ease up NOW or your heads
>        will eat themslves alive.  Take measures to correct the pinging
>        asap (like higher octane gas, retard timing, lower compression).
>BUY AND INSTALL GAUGES - It's one of those things where you can spend a
>        little now, or a lot later.
>

all good advice. gear it down and keep the revs up. Wave at everyone as
they drive by you cursing. It'll make them feel better.

>One more tip (I think this one is from the idiot book) - If you think your
>engine may be overheating and you don't have any gauges, stop and feel
>the dipstick.  If you can hold onto it for a few seconds without burning
>your hand, you're probably okay.  If you burn your hand, your engine is
>running way too hot.

that sounds about like my "sit on the bumper" test.

In any case, if you're going to stop, you'll probably need to let it sit
for 30 minutes or longer. break out the snacks. check out the wildflowers.

-rick

Rick Gordon
Bainbridge Island, WA, USA
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