# water pump and pulley mismatch



## Joust (Jun 6, 2009)

I've read up and cannot find pertinent information.

My original water pump on my 400 is 4inches long from the gasket face to the pulley mount face.
a replacement is 4.5inches long. this throws off the pulley alignment.
I cannot seem to find either a short water pump or a different pulley

with the alternator mounting as it does and the power steering pump like it is, how would a longer water pump ever work?
my engine is a 1971 400.
maybe I need a different power steering pump bracket to use the longer water pump?


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## Joust (Jun 6, 2009)

I found this 
" Many early ’69 Firebirds and GTO's used a pump that measured 4” long (casting# 9796351) and the pulley was 2-1/4” in height. From late ’69 to ’79 only one pump style was used, it measured 4-1/2” long and there are at least two different casting numbers used: 482138 and 488296. The matching pulley should measure 2-5/8” in height."

so I would need one of these 2-5/8" pulleys.


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## 05GTO (Oct 6, 2004)

You can find the 4" water pump at Ames Performance, the part number is N140NP and it list for $36.


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## Joust (Jun 6, 2009)

05GTO said:


> You can find the 4" water pump at Ames Performance, the part number is N140NP and it list for $36.


so it is. thanks...
I found a pulley locally. I'll check it out tomorrow but if it doesn't pan out, I'll just buy this pump.
thanks again


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## Slammd69 (May 24, 2011)

*Pulley size*

I have the same problem but would like to keep with the long pump style due to it being easier to find/replace but don't know what size pulley to run or where to find one? Mine is a 69 lemans 350 with a/c & ps. Please help


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## pontiac (Mar 6, 2011)

run an ad here for the pulley you need.


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