The Stovebolt Site Forums The Shop Area Engine Shop 302 6 cyl. waterpump problem - THE END

I've had to replace the worn out non GMC truck radiator with a new correct style GMC truck radiator . The problem is the fan is now in Contact with the back of the radiator . Is there a short shaft water pump made for the 1952 GMC 302 6cyl ? I am not a engine whiz but would the 235 6cyl short shaft water pump fit the 302 ? Any help to this question would be happily taken . Thank you ED

The stock radiator should give plenty of clearance. Is it posible the mount was modified for the other radiator?

I'm not aware of a "short" pump for a GMC engine.

Lot's of guys on the discussion board at www.oldgmctrucks.com run 302s. You'll have to sign up and do a search.

Are you sure you got the right fan and pulley?

I checked the radiator mount found no modification . Have the correct fan/pulley even the original motor . The old bad non-GMC radiator only had about 1/4" clearance . Back to PONDERING hair pulling and colorful language . Thanks For the suggestions !

Perhaps your new radiator is a 4 row or similar, a Desert Cooler type?

Wellllll Folks I'm here with egg on my face . NEVER listen to what people tell you it IS look for your self and research . The bloody engine is a 248 not a 302 and the truck is a 303-24 not a 450-30 . The wheel base of 185" does not fit any manuals list I have seen . OH WELL ! Back to the radiator . It is a desert cooler 4 row radiator . I can cut the mounting flang off and slide the whole radiator into the old radiators mounting frame and it should work . After measuring forteen ways from sunday that is . At least that's the plan at the moment . Thanks again for the help ! ED

It shouldn't make any difference if its a 248 or a 302 or a 300 or a 450. Back in the 50's I put radiators out of 450's in pickups and ran 228 248 270 and 302. Radiator clearance never was a problem, but keeping cool was. I finally fabricated shrouds and that fixed it. Is it possibly a Chev fan. I have some chev motors laying around that came out of GMC parts trucks and it looks like the fan sticks out farther.

Thanks I will have to check the fan. I do know it's 2" front of blade to back of blade. ED

Had a friend call me and ask me about the fan blade measurement . To clear up my somewhat simple answer - the 2" is the area the fan blade occupys - takes up - space it uses - it's pitch - not the physical width of the blade itself . Now that that's as clear as mud I'm back to work as soon as the new waterpump comes in . ED a clueless newbe new guy FNG ect... Yall have a good day .

The end of the story ! Ok the engine was a 248 not the 302 . I got a new GMC desert radiator and the fan would not fit with the new radiator . Got a new smaller pitch fan and that did not work (it just touched the radiator ) . Had to do what I was not wanting to do - modify the new radiator . Cut the mounting flanges off . Took the spot welded - mounting yoke with it's mounting flanges off of the old radiator . Some chopping and fitting on that and the new radiator slid into the the modifyed yoke-flange setup . Slid the whole thing into the trucks radiator frame and it fit like a glove . Bolted her up put in a new thermostat put on new hoses added fluid and fired the puppy up . YAY!!! No problems and the next day ran the Big Bolt in her first 4th of July parade and again no problems . I don't know if my trucks set up different in it's radiator mount set up but the new repro-radiators mounting flanges arn't recessing the radiator away from the engine enough and the angle is off also . Live and learn . Thanks to all who have sent tips . ED