Date: Thu, 7 Feb 2002 08:22:30 -0500
Reply-To: "G. Matthew Bulley" <gmbulley@BULLEY-HEWLETT.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "G. Matthew Bulley" <gmbulley@BULLEY-HEWLETT.COM>
Organization: Bulley-Hewlett
Subject: Re: Cool Air-Cooled (long)
In-Reply-To: <3C61C65D.486368E0@netins.net>
Content-Type: text/plain; charset="US-ASCII"
I recently posted a somewhat lengthy diatribe on gear shifting on
air-cooled motors, which covers a lot of details on how the stock
cooling system works.
The factory-designed cooling system, in its stock configuration is more
than adequate for a stock engine set-up, (94mm x 71mm), even pushing the
Westfalia through the desert fully loaded at 70mph (no AC).
Though some have suggested creating "ears" for the intake vents at the
rear, this changes them from highly efficient 'laminar flow' vents, to
far-less efficient 'ram air' vents. Though I have no data to prove one
way or the other, I feel safe to say that if VW thought that ram air
vents were superior (like they used on the T2 Bus) they wouldn't have
switched to laminar flow type on the T3. Genug enough? Wunderbar.
Some small things you can do that are helpful to the stock set up:
1. Use copper PermatexR between all the pieces of tin-ware to
eliminate air leaks.
2. Make sure ALL of your tin-ware is present, is cleaned on the
cooling-air side, and in good shape. DO NOT ELIMINATE ANYTHING FROM THE
STOCK SET UP (particularly the thermostat flaps, and warm air guides).
3. Replace any missing screws, use larger washers on holes that
have wallowed out.
4. Install the engine-to-body foam seal correctly (with the split
at the TRANSMISSION side of the motor. Make sure it seals against the
body completely, gently bending the tin if necessary to ensure a close
gap.
5. Make sure the rubber gasket between the oil-cooling tin and the
oil cooler is in good condition.
6. Make sure your spark plug hole gaskets are in place, and seal
correctly. If you can find them (Porsche dealer?) there is a much better
spark plug hole gasket which creates a positive seal by forcing itself
into the hole in the tin ware like a cork, with the HT lead running
through the center. If you can find these USE THEM.
7. If you had AC and removed it, carefully fashion a block-off
piece of cooling tin.
8. Never "lug" the motor. This cooling system is completely
dependant on crank speed, so if you are demanding heavy labor of the
motor, downshift to a lower gear, run the motor at much higher revs, and
allow the cooling system to do its work.
All that being said, most of the heat issues with this motor are in the
upper end (heads, cylinders), and these are air cooled. Without
switching to a CorvairR-style or 911 style fan, there is little you can
do to increase cooling, but you don't need to either if you have a stock
or near-stock set up.
One thing that can help, which I have incorporated on past Type 4's is
an external supplemental oil cooler with thermostat. This will help the
oil shed more of its heat, and in turn will help cool the motor's bottom
end. There are many different brands and set ups, but DO NOT eliminate
the stock oil cooler, supplement.
My set-up on our Westy is similar to the set-up I've used on previous
T2s with success. Today it is partially installed, but not functional,
so I can't send pics, but here is a description of the parts and layout.
The coolers are up front behind the grill, and consists of a crappy
8-pass "quik cool" and a 32-plate Baja oil cooler in series, with 1/2"
copper lines (bendable water/refrigerator type from plumbing supply
place) running to and from the engine under the van. Make sure these are
grounded and well supported. Make sure the lines going INTO the cooler
are at the bottom of the cooler, and the lines running OUT of the cooler
are at the TOP to prevent surprising air bubbles. You need a flaring
tool and some decent fittings to transition the copper to the coolers
and the other parts.
I have an OilStat (I think that is the brand) 180 degree thermostat and
relocated oil filter behind the left rear wheel, and a spin-on
"block-off" adapter where the filter normally hooks up, with 1 foot
rubber hoses to accommodate twisting of the motor. A blue-printed
Melling 31mm pump pushes the whole thing.
If I had it to do over (which I may do soon), I would use a single,
larger cooler up front, (perhaps an AC condenser core?). All this
oil-cooling is nice, but it is just icing on the cake. Remember, the
real danger on Type 4s is in the heads. Spin the motor freely, and keep
all the stock pieces and the factory settings, you should be okay.
From historic, walkable Mount Olive, NC,
G. Matthew Bulley
Bulley-Hewlett
Corporate Communications
Business: www.bulley-hewlett.com
Alliance: www.ntara.com
Home: www.MountOliveNC.info
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On Behalf
Of Chuck Hill
Sent: Wednesday, February 06, 2002 7:12 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Cool Air-Cooled
So what are the secrets to having an Air Cooled Vanagon that runs cool?
The Vanagon, especially the Westy, has the frontal area and the weight
to work the air-cooled engine pretty hard at times. What are the things
that you folks can point out to us to help make these engines last?
I really have an interest, having one of Peter B's rebuilt engines here
to install, and I'm planning on driving it on vacation the last of
March.
Does anyone want to tell us the secret of Jake Raby's cool running type
4 engines?
Chuck Hill