Re: [T2] Oil cooler lines

[George Lyle <glyle@xxxxxxxxxxxxx>]

On Fri, 14 Sep 2001, Stan Wilder wrote:

> I'm about to mount an additional oil cooler on my 1983 Air Cooled 2000cc.
> I'm using a sandwich type filter adapter and a stock (standard cooler for
> the 2000cc) additional VW cooler.
> I'd like to put it forward of the rear axles under the van for plenty of
> air flow and was just wondering about the distance that I can run the
> cooler lines, I've noted that Porsche runs a cooler on the front about 9
> feet from the engine.
> Are there general guidelines as to how far you can run oil cooler lines?

IN general, you want to keep the lines short, as the longer they are the
more pressure loss you will get and therefore the less flow.

That being said, if you do have to run long lines they have to be larger
in diameter.  I'm not familiar with the Porsche setup, but I'll bet they
either run large metal lines, or use us bypass cooler setup so that the
pressure to the bearings would not be lessened.  Metal lines would be
preferable as they would dump some heat themseleves and be less prone to
deterioration.

On cooler placement, don't assume that a location will provide airflow.
The eddys and currents around a moving bus are hard to predict!  You're
better off to provide postive airflow with a fan, along with some sort of
duct to prevent hot air recirculation.  The hot air exhaust should be
several feet from the inlet.

Speculation session:

The best oil cooling setup would simply take oil from the sump, run it
through a cooler, and return it to the sump.  This would entail another
oil pump or perhaps a dual pump as installed in the autostick bug.  This
way the bearings would not have the restriction of the cooler in the
path and would always see full pressure.

Obviously the factories haven't embraced this technology, except in
dry-sump motorcycles, so I might have overlooked some deficiencies.

George Lyle