This stinks!!!
Thread Starter
Melting Slicks
Joined: Aug 2000
Posts: 2,388
Likes: 42
From: Murrysville PA
This stinks!!!
This water pump has set me back hundreds and it made it two miles! This was a correct undated pump for my car (65 - 365) and now it’s junk. It’s probably the original pump. Apparently the guy who rebuilt it didn’t do it right or the parts didn’t hold up. I have a new one coming from Paragon with the incorrect 3/4” bypass hole. I also ordered a flush type bushing so I’ll see how that works out. This isn’t what I was hoping for.
Last edited by 89vette; Nov 9, 2017 at 06:45 PM.
Race Director
Joined: Apr 2015
Posts: 17,571
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From: Fresno California
I've seen hundreds, maybe thousands, of failed water pumps. Not one failed like that. My guess is that it was cracked when the impeller was being pressed on---- on a hydraulic press....and it let go entirely when in use. That is not a 'normal' type of failure AT ALL.
Melting Slicks
Joined: Apr 2010
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2018 C2 of Year Finalist
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I agree with GTOguy, and think you should talk to the rebuilder. I would suspect there was a flaw in the casting that he didn't detect. If it's one of the well know rebuilders (in OK?), I believe he would make it right.
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Burning Brakes
Joined: Sep 2016
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From: McMinnville Oregon
Many many years ago driving to San Diego and just south of San Jose on a Sunday where I needed to be at work in the morning. My brand new Triumph TR4 blows steam out the hood. I pull over and a cop stops and says a mile down the road I can find a water hose then turn back 3 miles to a station where I might find a mechanic. The mechanic found the impeller, brass, spinning on the shaft, steel. Sorry can't fix, great. But he said he could drill a hole thru them both and press in a steel pin. He did and it was still in there over 100,000 miles later.
Drifting
Joined: Dec 2006
Posts: 1,946
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From: Bronx New York
Years ago a cooperative counter guy at the local big parts retailer let me look at all the water pumps he had in stock and i got a rebuilt 326 casting for my 67 L79 for $30. The bypass was 3/4" though..
Race Director
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From: Canada's capital
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Never seen one split like that. He must have cracked it when he pressed in the new parts, or the bearing was too large a diameter. I'd have a 'chat' with him about his methods and what he's going to do to make it right.
Le Mans Master
Joined: Feb 2012
Posts: 5,407
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From: Glen Allen VA
Rebuilding should not put stress on that casting other than when the bearings and shaft are pressed in. Not so much. All other operations are pressing against the shaft and the housing is just along for the ride.
Race Director
Joined: Apr 2015
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From: Fresno California
Rebuilding shouldn't. but it looks like it did, in this case. A cocked bearing, an oversized bearing, a bearing driver off-center and too much pressure, etc. etc. Operator error here, IMO, for the guy who attempted the rebuild. The OP is extremely lucky he did not take out his radiator and hood, which is very easy to accomplish with a fan/pump failure!
Le Mans Master
Joined: Jan 2002
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This !
Thread Starter
Melting Slicks
Joined: Aug 2000
Posts: 2,388
Likes: 42
From: Murrysville PA
So after all of this trouble, I come to find out that this was the incorrect pump. It is the correct casting without a date but its stamped GM6. According to Bill Mock the correct pump is stamped between GM1-4.
Le Mans Master
Joined: Dec 2007
Posts: 8,000
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From: Puget Sound
The bearing and shaft come as an assembly. I've rebuilt a few water pumps and the only explanation that makes sense is that the O.D. of the bearing/shaft assembly was too big. It should take little effort pressing it into the housing. Installing the impeller or the hub onto the shaft puts zero pressure on the casting.
Race Director
Joined: Apr 2015
Posts: 17,571
Likes: 3,460
From: Fresno California
The bearing and shaft come as an assembly. I've rebuilt a few water pumps and the only explanation that makes sense is that the O.D. of the bearing/shaft assembly was too big. It should take little effort pressing it into the housing. Installing the impeller or the hub onto the shaft puts zero pressure on the casting.