David,

Strange. In the last two months there have been three tanks on my 91
GL. In both cases before I put a new one on, the short neck for the
fill cap/valve was split, spewing coolant from the exact same place on
both. I have had no cracks in the areas around the perimeter as your
pictures show.

I have never had a coolant tank failure on my two other vanagons (that
I can recall). Maybe these are all getting to that certain age...

Jim

On Mon, Feb 21, 2011 at 5:55 PM, David Beierl <dbeierl@attglobal.net> wrote:
> I recently pulled the coolant pressure tank on my '89 2.1l WBX and
> found three significant stress cracks that looked ready to
> fail. �Photo of one here:
> https://picasaweb.google.com/dbeierl/Vanagon1989PressureBottleStressCracking#
> - it looks worse in person than in that still-installed flash picture.
>
> I would suggest draining and removing the tank and examining it with
> a strong light shining through it from behind and above. �The
> likeliest areas for stress cracks are at the areas immediately above
> and below the joint running around the circumference; the third crack
> on mine was on the neck, in line between the pressure cap and
> low-coolant sensor. �The first two (one above, one below) were long
> and clearly formed by repeated flexing of the tank. �I estimate that
> patching them on the road would be very difficult except by plastic
> welding, because of the proximity of the joint. �The third was much
> shorter, gaped open in the middle and was of a different character
> generally. �If I learn anything of significance about it I'll say so.
>
> Yours,
> David
>