[J.C.you]

Anyone rebuild their own pumps here? Any tricks? I have a date coded one I need to rebuild.

[Goatracer1]

When I worked for Pontiac the owner's teenage son rebuilt the water pumps so it can't be too hard.

[mgarblik]

When I worked at the Pontiac dealer, they would not pay for a new water pump under a warranty claim. You had to take it apart and attempt to rebuild it. The warranty was 5 years/50K miles. About half of them had enough grooving in the shaft in the area of the seal, that the zone would authorize a new pump. The other half, you could clean up the shaft with 400 paper. Then pack the seal inside where the garter spring is with some grease so it stays in place and press the thing back together. Take note of the exact location of the impeller on the shaft as you want to go back in the same location. All the pumps in those days had a cast iron impeller. I would not reuse a sheet metal one. Also, make sure the iron one goes back on with a press fit. If the press has a gauge, I would expect at least 750 LBS. minimum press. Good luck with it. Didn't know you could even get seals and bearings anymore . At the dealer we had to rebuild, power steering pumps, starters, alternators, master cylinders, wheel cylinders, calipers, brake boosters, steering gears and racks, all that stuff.

[J.C.you]

Ok, a buddy of mine that worked at the Pontiac dealership in the early to mid 70s said they would break about half the housings trying to cold press them out. Pontiac wanted them to rebuild them rather and hardly gave any time for the rebuild job under warranty. So the mechanics could actually make more by just removing and replacing with a new pump.

After cold pressing and breaking a Guinea pig housing, I took a torch and cut the fan mounting flange on my number matching pump. The old bearing assembly came out heated housing easily without breakage.
Had to put a little heat on the fan mounting flange going back with the assembly. Otherwise no problems.

[chuckies76ta]

I had 3 of them rebuilt, but were done by Cardone industries . https://www.cardone.com/rebuild-and-return/

[mgarblik]

Originally Posted by J.C.you

Ok, a buddy of mine that worked at the Pontiac dealership in the early to mid 70s said they would break about half the housings trying to cold press them out. Pontiac wanted them to rebuild them rather and hardly gave any time for the rebuild job under warranty. So the mechanics could actually make more by just removing and replacing with a new pump.

After cold pressing and breaking a Guinea pig housing, I took a torch and cut the fan mounting flange on my number matching pump. The old bearing assembly came out heated housing easily without breakage.
Had to put a little heat on the fan mounting flange going back with the assembly. Otherwise no problems.

I do remember breaking a casting at the dealership. The parts department gave me a replacement water pump. I asked for a can of Pontiac blue paint for the cast iron. I had been at the dealer about a year and was the "newbie" on the line. The other techs came over as I masked off the fan hub and painted the new water pump. "What in the hell are you doing?". "Is there a flat rate time for painting a water pump?". I will never forget that. The dealership made me pay for the can of paint. It was the difference between doing it half azzed and doing it right. I was made fun of for doing that for months.

[johnta1]

Here's a Service Bulletin on rebuilding them:


Water Pump Rebuild

With correct tools and rebuild kit makes it sound easy.

[Half-Inch Stud]

Fwiw; i had a known-good Aluminum Water Pump sit on the shelf for about 10 years. All looked clean, no shaft rust, etc. Went to use it and it leaked from the weephole.

Front seal dried up.

Went searching for Water Pump rebuild kits, but tossed the core and bought new. Price of new went up since i bought a few.

['ol Pinion head]

Exactly, & the front seals do dry up with those near 50 year old GM service package bearing/seal kits. Main reason I don't use them. Another problem with an eBay or swapmeet purchase of one of the long discontinued GM water pump service kits is, there are at least 2 different dimensions of cartridge bearing/seal. Need to have the correct one.

Missing the correct cast impeller as it was replaced by a mass rebuilder years ago with a stamped steel impeller, there are 5 different cast impellers used from '63-81 on original Pontiac V8 water pumps.

[bill ryder]

Arthur Gould, on east coast. Just tell them you want your original core back. Excellent work for 40+ years! Very inexpensive!

"Bill"!

[gto4ben]

I've rebuilt many of my water pumps for my 67 LeMans and 67 GTO. Pontiac used to sell rebuild kits that had a new shaft, seal, etc packaged in a nice case but those are long gone. I made my own kit. You'll need to have a hydraulic press to be able to remove the front flange using a bearing separator and to be able to remove the impeller and seal out together. Both the front flange and impeller will get reused.

Tractor Supply part houses have the parts, at least for the 8 bolt pumps. The bearing shaft that I chose is longer on one end than required but is sawed off to the correct length. The seal kits come with an plastic installation tool. AR62933 is the seal and JD9212 is the bearing/shaft. Replacement shaft diameter is a few thousandths over for a good press fit.

Amazon sells the pump shaft bearing and seal as well but the tractor supply houses usually have lower prices. I included my inventory of used shaft bearings' dimensions and some part numbers that should work.

[J.C.you]

I bought the kit off eBay, had all the components and cast impeller. No problem… Using a little heat to remove the old bearing and shaft. Then heat on the fan flange on assembly. I believe where one could have a problem is not getting the .425 preload they recommend on the seal installing the impeller.Think the kit was $85.

[unruhjonny]

this post is pure gold for me...

Thanks to everyone for sharing this!!

[DaleO]

A question. A guy reads that the cast impeller vs the stamped is the right way to go but I don't understand why. It would appear that the bigger vanes of a stamped impeller would grab the water and circulate it better than the shorter (that I've seen on the ones I've installed) cast version. I've not had issues with either as far as that goes.