Aluminum Water Pump Rebuild
 

Calling DIYers: Anyone use one of the rebuild kits (link below)? My aluminum short pump part number is 3975928 (GM OTC for BBC applications). Multiple vendors provide kits but, can not confirm whether the kit can also work with an aluminum pump, only that they are for 396/427 application. Most of the pumps for this application are, of course, cast iron.

Thanks, Sam


https://www.zip-corvette.com/66-74-4...build-kit.html

I source the Ebay Kits that come with a Cast Impeller & single pattern drilled hub.

I do pumps DIY style and have never tried doing a Alum, I wonder what the added risks are given the delicate alum structure. As in Support could be WAY more critical of a softer metal structure?

Hum

I had my aluminum pump rebuilt a few years ago. The company that did it wouldn't disassemble it, so I had to do that myself. They said they couldn't guarantee that they could get it apart without breaking the casting. I took it apart and sent it to them and they did a good job putting it back together.

I looked at the Zip stuff a while back, but their offering on the long water pump kits did not look proper to me.

I bought a few of these kits from these guys in Oregon off Ebay. They worked perfectly for my cast iron 69 Camaro water pumps. Supporting cast iron pumps in the press is very important, I would think Alum ones are even more important!

1969 Chevrolet Camaro Z28 302 5.0L V8 New water pump rebuild Kit 3927170 3953692 from 2ndgenautoparts

I second using 2ndGenautoparts off EBay.
Very nice quality rebuild kits.
And, great customer service. I rebuilt my first water pump last month and the owner texted me to answer my questions.

Good day Sam, TRACY PERFORMANCE 1 586 722 0000 can help you out. I think you have 1 extra 5 in your part number. He has done 3975928 pumps before and could supply a kit for you. Marc.

Be VERY careful at Home

LOL

My 68Z Pump! - Gone done by ME!
Sometimes you just end up kicking your own arse
It was dated 66' and was serviced at some point. I ended getting a 1967 dated correctly from a vendor. They (GM) went to a larger Bearing in 1970' I think and making sure you get the correct kit is important. Then Properly Setting the internal seal is tricky that required special tooling

Wow,all good inputs. I appreciate yr suggestions and YES I did add an extra “5” in my part number. Good catch. I’ll report back on which direction I go.

Thanks again!

Best,
Sam

YOu are a courageous man showing a sad outcome but, you’re willingness to show the rest of us so we can learn from you is noteworthy. I doff my cap to you sir!!:biggthumpup:

Update. I have a GM aluminum water pump due here this week. I received the rebuild kit from 2ndGenAutoParts. I also got their 3D printed special tool to install the bearing to the shaft.

https://2ndgenautoparts.com

Ignore the hub in attached photo - they substituted the correct 8-hole hub in my kit.

Any best practices for cleaning up the aluminum pump?

Thanks!

A good degreaser for alum like simple green (purple power will etch aluminum if left on any length of time). I read brakeclean works well too as a final rinse. I use my glass beader to clean lots of metal. For rusty iron I have a 2nd cabinet with coal slag for aggressive cleaning :)

"I also got their 3D printed special tool to install the bearing to the shaft."

Do you Mean the Special tool for the Dynamic Seal install tool>? I made custom-mine on a lathe using Alumn Stock.

Be Very careful pressing in the Seal.

& use the Chassis Overhaul Manual as a Guide.

Oh & we all make mistakes when Truley performing DIY. I can not even fathom being a Pro and rebuilding for a fee. I would go nuts.

Yeah, that tool of yours is a bit finer than mine. Very nice! I do have that manual and plan to follow it closely. I know it’s very important to support the pump when pressing in the seal. Yes, I meant the dynamic seal. Any other specific tips for pressing in the seal? Thanks