BB Water pump rebuild kits
Thread Starter
Advanced
Joined: Dec 2024
Posts: 80
Likes: 40
From: The Plains, VA
2025 C3 of the Year Finalist - Modified
BB Water pump rebuild kits
So, BB water pump rebuild kits are out of stock everywhere that I have looked and have been for nearly a year. Suppliers are less than forthcoming, estimating in stock soon every time I have reached out. Rebuilt pumps are available, so the parts are available to someone, just not me. If I want to keep my pump it seems that my only current option is to buy a rebuilt pump, deconstruct it and harvest the parts for my pump. Does anyone have any better ideas for this situation?
Safety Car
Joined: May 2001
Posts: 4,759
Likes: 1,647
From: Fairfax Virginia
If it were a name brand pump you might be able to get it rebuilt. That is a good point, I don't think they want us to rebuild water pumps anymore.
I upgraded (?) my water pump from a cast iron Stewart's Stage 2 to an aluminum Edlebrock BB Shiny water pump which they claim is "better than the original". The slightly used Stewart's pump is available if you want a replacement that is better than the original for a BB Mark IV. The pump was replaced entirely for the weight loss, looks and features of the new Edelbrock water pump, the old pump has less than 10,000 miles of well lubricated coolant use.
The aftermarket electric water pumps have lots of rebuilding parts available. I might go that direction as I don't drive the 1968 C3 that far any more. For cross country driving then stick with a conventional water pump for reliability. For shorter driving the new high flow water pumps might make sense.
I upgraded (?) my water pump from a cast iron Stewart's Stage 2 to an aluminum Edlebrock BB Shiny water pump which they claim is "better than the original". The slightly used Stewart's pump is available if you want a replacement that is better than the original for a BB Mark IV. The pump was replaced entirely for the weight loss, looks and features of the new Edelbrock water pump, the old pump has less than 10,000 miles of well lubricated coolant use.
The aftermarket electric water pumps have lots of rebuilding parts available. I might go that direction as I don't drive the 1968 C3 that far any more. For cross country driving then stick with a conventional water pump for reliability. For shorter driving the new high flow water pumps might make sense.
Drifting
Joined: Jun 2025
Posts: 1,731
Likes: 600
So, BB water pump rebuild kits are out of stock everywhere that I have looked and have been for nearly a year. Suppliers are less than forthcoming, estimating in stock soon every time I have reached out. Rebuilt pumps are available, so the parts are available to someone, just not me. If I want to keep my pump it seems that my only current option is to buy a rebuilt pump, deconstruct it and harvest the parts for my pump. Does anyone have any better ideas for this situation?
me thinks this may be your best route.
A local shop that still rebuilds on site. They do still exist.
Seek them out. Perhaps they'll either rebuild yours or offer to supply rebuild parts Or even give you their contacts for parts.
Old Pro Solo Guy
Joined: Dec 2017
Posts: 8,095
Likes: 4,449
From: Marlton NJ
All C3 water pumps are short, both SB & BB.
There are two versions of the BB C3 water pump, early and late C3.
Your late one should have a 3/4" pilot sticking out that goes thru the pulleys.
The earlier pilot was smaller and uses completely different pulleys.
That main shaft will get replaced when it is rebuilt.
Make SURE they get that main shaft size right, they are both 3/4" bearing sized shafts, but the late one has a 3/4" pilot and the early one was turned down to 5/8" pilot.
And have them double check the pulley hub height before they take it apart, and again after they press the new hub on.
Measure it your self, or have them do it, and show you, before and after.
C3s are different than other chevies. And different early and late.
Get it wrong and the belts will not line up, and they will squeel, or the pulleys will hit the pump.
The only casting number for the late 3/4" pump is 330813.
There are 3 casting numbers for the early 5/8" pumps, #3856284, #3940960, and #3992077.
Hub heights varied 1/4" also, hub to block.
Early 5.545"
71-74 5.795"
The castings are date coded as well. Write yours down first.
Trust, but verify.
I got the following info from the Edelbrock site.
Somebody somewhere has a measurement wrong.
The Eddy site also ignores the 65-67 BB C2s & the 68 C3.
Measure yours first!
BB Pump Measurements From the Edelbrock site:
Short-Style Pump (5/8" pilot shaft) #8850 #8860 #88502 #88504
Fits all 1965-68 B/B Chevy passenger cars, 1966-72 trucks and 1969-70 B/B Corvettes. Has 3/4" ball/ball bearing. Dimension from block surface to hub: 5-3/4". Inlet diameter: 1.95".
Long-Style Pump (5/8" pilot shaft) #8851 #8861 #88512 #88514
Fits 1969-87 B/B and some 1988-91 heavy-duty trucks with Mark IV engines. Does not fit Corvettes or trucks over 1-ton. Includes 3/4" ball/roller bearing. Dimension from block surface to hub: 7-5/16". Inlet diameter: 1.875".
Short-Style Pump (3/4" pilot shaft) #8852 #8862
Fits all 1971-74 B/B Corvettes. Comes with heavy-duty 3/4" ball/roller bearing. Dimension from block surface to hub: 5-3/4". Inlet diameter: 1.95".
There are two versions of the BB C3 water pump, early and late C3.
Your late one should have a 3/4" pilot sticking out that goes thru the pulleys.
The earlier pilot was smaller and uses completely different pulleys.
That main shaft will get replaced when it is rebuilt.
Make SURE they get that main shaft size right, they are both 3/4" bearing sized shafts, but the late one has a 3/4" pilot and the early one was turned down to 5/8" pilot.
And have them double check the pulley hub height before they take it apart, and again after they press the new hub on.
Measure it your self, or have them do it, and show you, before and after.
C3s are different than other chevies. And different early and late.
Get it wrong and the belts will not line up, and they will squeel, or the pulleys will hit the pump.
The only casting number for the late 3/4" pump is 330813.
There are 3 casting numbers for the early 5/8" pumps, #3856284, #3940960, and #3992077.
Hub heights varied 1/4" also, hub to block.
Early 5.545"
71-74 5.795"
The castings are date coded as well. Write yours down first.
Trust, but verify.
I got the following info from the Edelbrock site.
Somebody somewhere has a measurement wrong.
The Eddy site also ignores the 65-67 BB C2s & the 68 C3.
Measure yours first!
BB Pump Measurements From the Edelbrock site:
Short-Style Pump (5/8" pilot shaft) #8850 #8860 #88502 #88504
Fits all 1965-68 B/B Chevy passenger cars, 1966-72 trucks and 1969-70 B/B Corvettes. Has 3/4" ball/ball bearing. Dimension from block surface to hub: 5-3/4". Inlet diameter: 1.95".
Long-Style Pump (5/8" pilot shaft) #8851 #8861 #88512 #88514
Fits 1969-87 B/B and some 1988-91 heavy-duty trucks with Mark IV engines. Does not fit Corvettes or trucks over 1-ton. Includes 3/4" ball/roller bearing. Dimension from block surface to hub: 7-5/16". Inlet diameter: 1.875".
Short-Style Pump (3/4" pilot shaft) #8852 #8862
Fits all 1971-74 B/B Corvettes. Comes with heavy-duty 3/4" ball/roller bearing. Dimension from block surface to hub: 5-3/4". Inlet diameter: 1.95".
Last edited by leigh1322; Jun 4, 2026 at 10:13 AM.
