Thread: advice on temp
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Old 07-07-2022, 12:07 PM
78w72 78w72 is offline
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Join Date: Nov 2007
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Quote:
Originally Posted by george kujanski View Post
Out of the factory, I would think that the water pumps were manufactured with the impellers accurately pressed onto the shaft, probably unlike what we get from rebuilders. 50+ years later, how many untouched water pumps still exist?

Is there any evidence that most stock engines operated well with large impeller-to-plate clearance? I doubt it.... that’s contrary to the design of the type of pump. Proper clearance is mandatory for proper operation. In my case specifically, simply reducing clearance made a substantial improvement in cooling.

George
out of the factory the clearance was not what guys do today is what i meant, the clearance trick will get that gap to .015-.020. pretty sure they were never like that from the factory. i have changed a factory original pump & it had what most would consider a very large gap. many on here dont do the clearance trick & the gap can be all over the place. FJ may chime in & comment on how hes never done it & has no issues. just saying its not needed for a pontiac engine to run cool but is definitely a good idea to do.

myself & so many others back in the late 80's to early 90's on higher HP engines didnt know about the clearance issue, on my old 455 it was closer to 1/4-3/16", that car ran cool in any temps or situations with a crappy old repaired stock radiator.