coolant loss/auxilliary water pump

Phil Rose pjrose at
Fri Feb 18 10:19:46 EST 2005

A few days ago in a thread about coolant-level warnings, I mentioned 
that my car had recently started to have significant  coolant loss. 
After studying the tell-tale signs it became obvious that the source 
(or _a_ source) was seepage from the auxilliary (after-run) water 
pump. Fortunately I had a new pump on hand, and the replacement was 
about the easiest job I've ever done on this car. About 10 minutes.

When I examined the old pump, I expected there to be some evidence of 
"cracking" in the plastic housing --somewhere near the hose nipples. 
I pulled on the nipples (ouch!) anticipating that one of them might 
snap off--but no. What happened was that the entire pump housing 
separated from the motor. So it appears that the seepage was from the 
"joint" between the plastic housing and the metal pump. Is this 
typical? I expected the sort of stress crack as in the radiator 
nipple failure mode. Anyway, I expect that the old pump was the 
original, in which case the failure came at about 150K miles. That's 
one less component to worry about now--until 300K comes along :-)


Phil Rose
Rochester, NY
mailto:pjrose at

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