The Stovebolt Site Forums The Shop Area Engine Shop GMC 248 Water pump Q

1950 GMC 1.5 Ton Truck with the 248 I-6

Went to go start it and noticed it needed water.... but when filling, water came out of water pump shaft. (New pump, right).

Okay, local NAPA says they can get new pumps for about 120.00 BUT they said that the book only goes back to 1954 for the 248. Now, will the 1954 water pump fit on my 1950????

I want to put a 'new' one one or get one w/out having a core charge (since I'll have the old one rebuilt as a spare).

Thanks for the help. By the way, this GMC is still being used... old farm rig. We don't retire em.... we just use them then rebuild them and use them.....

The same water pump fits all GMC's from 1939-1959 including the 228, 248 ,270, and the 302. The only difference is in the pulley size. If you use a puller to save your old pulley you are in business..

Awsome... that's what I thought. I plan to use the old pully.

Stovebolt has them for $45.

Guys the pulley doesn't 'Just pull off' I broches em they never fit again....I've no idea how my rebuilder does it but a puller ain't it

When I changed my water pump 5 years ago, the pulley was already on. I couldn't figure out if it was pressed on or not. My 350 series Jimmy has the 248 and the wide pulleys.
I think it was about $65 and I had to turn in my old one for a core. The Filling Station has them as well........
I picked it up from Carquest right down the street..............

I pulled mine off with a puller and pressed it back on.. Not a problem..

I think it matters if you have a steel or iron pulley but press is better than puller

The GMC shop manual goes into detail about changing the pulley. Remember when pressing it back on to make sure you are pressing against the back of the impeller shaft and not against the pump body. You don't want to press the shaft through the bearing, you want to press the pulley on to the shaft.