Hi,

I concur, somewhat,  with Mark. The leak in one of my metal pipes was
right on a weld seam, as if there was some slag or other
imperfection. The rest of the inside of the pipe was pristine.

But the engine end of the pipe was corroded where it mates with the
rubber tubing. I assume that air can get makes its way in there,
however slow, and promote corrosion. In the rest of the coolant
system there should be very little dissolved O2 and the corrosion
inhibitors in reg changed coolant should take care of things.

I used the 1 1/4 ID marine hose (from Coast industrial here in
Victoria, so really not marine but industrial hose *S*). I had the
fuel tank off (the leak was right above the tank, noticed the orange
coolant stain when doing a tank R&R.

As I am a silly bugger I only replaced the one leaky pipe. I am
guessing I will have to do the other soon.

Alistair

'82 westy, diesel converted to gas in '94
http://www.members.shaw.ca/albell/

On 26-Jun-06, at 6:23 PM, mark drillock wrote:

This is not what I have seen. All of the original metal pipes I have
checked had major corrosion on the inside, even if they looked ok on the
outside. The pipes are made from seamed tubing.  The seam runs the full
length of each pipe. The seam is where the worst corrosion occurs on the
inside. One pipe does always look worse than the other. Even a pipe that
looks ok inside on the ends can have grape or pea sized nodules growing
elsewhere inside, along the seam of the pipe.

Mark

Roger Sisler wrote:

> ..............
>
> It turns out that only one of the two coolant pipes are usually
> corroded.
> This from the outside, to the inside. VW never seemed to learn to
> paint
> things black and not have the  paint flake off. Pulleys
> included.Check the
> inside of the pipes and you will see that they are perfect.
>
> .................
>