The only thing that ever happens to the water pump is bearing failure, seal
failure, and I have seen the impeller loosen and walk off the shaft until it
rubbed on the engine case. 
If a past bearing failure occurred the case can be damaged and enough wear
here can reduce pump efficiency at low or idle speeds. 
If the engine is cooling the pump is fine. If over pressure is happening you
need to check/replace the pressure cap and be concerned about loose/cracked
heads allowing combustion gasses into the cooling system. 

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Grungy
Sent: Tuesday, June 28, 2011 11:22 AM
To: vanagon@GERRY.VANAGON.COM
Subject: testing a water pump...

Is there a way to test the output of a water pump?

My '89 Carat with automatic blew the coolant line that goes from the side of
the thermostat housing to the "T"-pipe a week ago (it was 95�F outside, here
in Texas).
The hose is now replaced, but I'm worried that there may have been some
factor other than age that made the line blow.

The Carat has about 125K miles, and about 10K of those are mine.
The previous owner claimed to have had the engine rebuilt, but there's no
telling either when that was or whether the water pump was replaced.
--

bcnu - Grungy  (Houston, TX)  opinions are just that.obviously.
60 dddPanel 69 Bug 89 Carat 90 Vanagon GL (parting out) 05 Jetta Wagon TDI g
r u n g y AT g r u n g y DOT c o m