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[GMCnet] GM net] Figured out how to count water pump impeller [message #329025] Sat, 10 February 2018 10:45
fbhtxak is currently offline  fbhtxak   United States
Messages: 116
Registered: April 2006
Karma: 0
Senior Member
Bob, Ken,

The late Bob Drewes told me he did flow volume tests on pumps with the OEM
cast iron impeller and those with a stamped steel impeller. He said there is
no discernable difference. I consulted him when the OEM pump began to leak
and the only local off-the-shelf pumps I could find were those with stamped
steel impellers. I bought/installed that pump 10 years ago. The coolant temp
was/is the same as for the OEM pump under all loads.


Fred Hudspeth
1978 Royale (TZE 368V101335) - Tyler, TX
1982 Airstream Excella (motorhome) - Cooper Landing, Alaska

Message: 3
Date: Sat, 10 Feb 2018 07:05:07 -0500
From: Ken Henderson
To: GMC Mail List
Subject: Re: [
blades while pump is installed on engine

Content-Type: text/plain; charset="UTF-8"


Is your engine running hot? Or is its temperature well controlled at all
ambient temperatures?

I've run 'most every WP configuration at one time or another, including
running them backward with a serpentine belt with both modified and
unmodified housings. The last one I ran on the 455 was an emergency
replacement from AutoZone, caused by on-the-road failure of a reverse-flow
prototype from Leigh Harrison. I never noticed any difference in cooling
with ANY of them, even while monitoring with the digital readouts on the EFI

There have always been other things I could worry about more effectively, I

Ken H.

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