For the waterpumps:

There are 30 and 40mm hubs. You should have a 40mm
There are cast and pressed metal impellers, and cast plastic ones.
THe pressed metal one looks inferior to me. Pumps with different
impellers have the same part nr. It's just a quality difference.
Try different suppliers.

I've seen twice failed attempts to change the belt routing to
one belt running both water pump and alternator. Once was by
a "long time trusted mechanic". In both cases belt slippage
caused overheating and immediate death due to head warping
during highway driving.

Your problem is more likely the thermostat. Most are junk. Did you try a
brass "wahler" brand 87Celcius?

/Martin

   From: al brase <braseelec@forbin.com>

   Martin:
   I've got a 82 diesel van with lots of miles on it and the original sachs
   shocks lasted till 125k miles. I started using it as a work vehicle at
   100k and it is VERY heavily loaded. I scaled it at 5550 lbs. recently!
   So with that kind of load, the old shocks finally gave up.
   On another subject, I recently changed the water pump and now it runs
   too cold. I had a 95C thermostat in it and the guage  was always 3/4 of
   the way over. Now it barely moves off the left peg. I tried a couple
   different thermostats and they were worse. I believe the guage is
   accurate because one of those-15F days the coolant froze and then it
   overheated. Then the guage was on the right peg. Do diesels have many
   different water pumps? The guy I bought it from said the hub was the
   only difference and if I got the one with the right hub it would be the
   right pump. If you've got any ideas I'd sure appreciate them.
   thanks,
   Al Brase
   Waterloo, Iowa

--
Westy 1.9l Turbo Diesel
Quantum 1.6l Turbo Diesel

Martin Jagersand                 email: jag@cs.yale.edu
Computer Science Department             jag@cs.rochester.edu
Yale University

        Slow down and visit the VW diesel Westy page:
          WWW: http://www.cs.rochester.edu/u/jag/vw
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