Date: Sun, 12 Oct 1997 13:01:36 -0700
Reply-To: Malcolm Holser <mholser@ADOBE.COM>
Sender: Vanagon mailing list <Vanagon@Gerry.SDSC.EDU>
From: Malcolm Holser <mholser@ADOBE.COM>
Subject: Re: In the Dog House
Well, the Vanagon list is the wrong place to send such questions about
TypeI engines -- no Vanagons had these. But I'll send this to the list
as well, since it is VW, and maybe a lot of Vanagon'ers have not had old
VW's and might want to know, too.
The later Beetle engines had a *much* improved cooling system -- it
almost got as good as the TypeIV engines used in the '72-'82 Type 2's
(like the early Vanagons...). These are called "dog house" engines for
no good reason except somebody called one that once and the name stuck.
In the earlier engines (from 1938 until 1972) the oil cooler sat inside
the upright fan shroud, and the cooling air to the laft side of the engine
passed through the cooler, over the cylinders and out the lower rear of
the engine. The doghouse engines move the oil cooler something like 8cm
forward, and out of the fan shroud. There is a larger fan, and the air
is split into three paths rather than the old two. One goes to each side,
and the third is directed over the oil cooler, and out the FRONT of the
engine via a duct in the upper front engine tin. From the rear, the
engines look *very* similar, but if you reach around to the front, you
will find the extra ductwork. The ductwork completely blocks access to
the upper left engine mounting bolt, and doghouse engines have a nut
pressed into the case, using a bolt from the front (very awkward to install).
The doghouse cooling system is, in many people's opinion, the best of the
upright VW engine designs, and does very well in cooling the entire engine,
even if it's been souped up. To add external oil cooling to one of these
is very expensive if you actually want to improve things -- it is real hard
to improve on.
Apparently the term "doghouse" was applied because this additional ductwork
appears to be attached, somewhat as an afterthought, to the fan shroud, like
a dog's house tacked onto the "real" house. Where I live, doghouses are
free-standing affairs *never* attached to a house. Maybe in Germany life
for dogs is different. But the name is cute, and stuck.
To tell if you have a doghouse cooler, merely reach in front of the fan
shroud on the left side and feel. To see if you have the *case* from a
later engine, even without the tinware, feel the upper left engine mounting
bolt on the back side for a round raised pressed-in nut. There are some
other case differences, none major, like the mounting bolts for the oil
cooler itself.
For us wasserboxer-types, you can look at the engine case and marvel. A
lot of air-heads seem to think that we inherited horrid complexity when VW
water-cooled the old Beetle engine. Our engines look like Beetle engines
stripped of their duct-work. I'd suspect that there are about the same
number of parts altogether. It is a pain to deal with the coolant, but
sure makes it easier to actually see the engine. On a TypeIV engine, you
can only get peeks at the engine itself under all the tin.
malcolm
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