My 1970 455 Vista Cruiser with air started spraying water from the water pump today. A number of places (Rock Auto, OPGI, others) are out of stock on A/C sized pumps. The only one I've found is at Fusick's, a repro for $199. Any recommendations on best purchase options?

 

Could have yours rebuilt

 

I am pretty sure that GMB 130-2926 is the correct part number for a GMB pump but you might want to call them to be certain.

One bit of advice I have found out the hard way lately. There are two types of pumps being made. The cheaper ones have the heater hose nipples actually formed as part of the pump casting itself. The better pumps will have pressed in steel heater hose nipples just like the factory ones.

I know of two of the cheaper pumps that have failed pretty quickly. One was a customer and the other was the one on the 307 in my Wife's Riviera. I got the GMB pump from NAPA but others sell them too. Look at the two pictures attached and you can see the difference in the pumps. The first one is the "cheap" type that you do not want.

AC Delco pump




GMB pump

 

Watch out here..
Measure your current water pump inlet size and overall height of your water pump (gasket surface to fan mounting face) and make sure the replacement you buy matches.

Stock 1970 and older 455's water pumps have a 2" inlet size
Stock 1971 and later 455/350 water pumps have a 1.75" inlet size

Summit - OLDSMOBILE 7.5L/455 Oldsmobile V8 Water Pumps, Mechanical

 

These are just the kind of tips I'm looking for This is likely the original pump. I know I haven't changed it in the over forty years I've owned it. I want everything to bolt back and hook back up without having to reinvent something.

 

Yes if it an orignal style look here for casting number: https://classicoldsmobile.com/forums...umbers-160762/

dont rebuild some aftermarket one.. lots of cores out there if you need one, Need to know if you have heavy duty colling, AC, or NOT etc etc for proper length application. fan belt pulleys need to be matched for the application.

I demand having a cast iron impeller in the rebuild. as I think they flow better then the stamped "fan" type ones. A good rebuilder will know what I am talking about, you never see this in an aftermarket POS one.

I have used the following rebuilders and both have held up over time..

https://agrebuilders.com/

http://www.waterpumps.bizhosting.com/



Fred

 

Why consider a cheap quality aftermarket pump when you have the OEM pump which can be rebuilt? Stick with it; you won’t be sorry!

 

Looks like this one does not have a casting number on the inlet, so I guess it was replaced by the previous owner at some point. No point in rebuilding that.

 

I use flowkooler pumps on my 455’s and like them. They redesigned the impeller and I think it’s better.

Beyond all the good advice above, be aware there were 3 pump lengths.

Be sure to measure the one you took off and confirm the height of the replacment as the same whatever brand you choose.

Chris

 

As well as era-specific inlet sizes: