CRG Discussion Forum

Camaro Research Group Discussion => Restoration => Topic started by: JST69Z28 on March 27, 2024, 08:33:02 PM

Title: water pump question
Post by: JST69Z28 on March 27, 2024, 08:33:02 PM
The water pump on my 69 Z28 just started to leak at the shaft seal (photo attached).  I have owned the car since 1982 and never replaced it.  I have reviewed most of the messages from team members, but still looking for advice on 2 questions:
1. What is a J48 code? Most of the others I see have 3 numbers after the letter.   
2. If original, should I rebuild it and what's the best way get that done?

Thank you for all the great info on this site.
Title: Re: water pump question
Post by: 68camaroz28 on March 27, 2024, 08:40:09 PM
J48 equals Month, day, year
Title: Re: water pump question
Post by: Delco115 on March 27, 2024, 09:45:22 PM
J 4 8 ..... I believe that's November 4th, 1968. If not accurate, someone will correct me.
Title: Re: water pump question
Post by: David K on March 28, 2024, 03:12:49 AM
Definitely have it rebuilt or replace it and put it to the side. Replacing it is quicker.
I’ve never used their service, but they rebuild.
https://marvelousparts.com/pages/water-pump-and-smog-pump-rebuilders
Title: Re: water pump question
Post by: GMAD_Van Nuys on March 28, 2024, 04:25:02 AM
According to CRG, the water pump used on the 1969 302 engine was the same as used on other small blocks for 1969:

http://www.camaros.org/waterpumps.shtml
Title: Re: water pump question
Post by: KevinW on March 28, 2024, 12:22:45 PM
For an all original Z28, it is always better to keep/rebuild all components like water pumps. An early 69 model year pump like yours are more rare to find, so keep it!

There are some small rebuilders around that can rebuild and return your original pump.  If you have a press, you can do it yourself, but you will need to practice on other pumps and make some special press blocks.

I have rebuilt my pumps using a kit from ebay (northwest supplier) which have worked well.


New pumps will not look the same as your original and have the part number 3953692. Almost everything has a part number and people will look for that to authenticate a Z.  my .02
Title: Re: water pump question
Post by: Petes L48 on March 28, 2024, 02:41:37 PM
J 4 8 ..... I believe that's November 4th, 1968. If not accurate, someone will correct me.

For cast date codes, "I" was used for September, so his "J" would be October:
http://camaros.org/numbers.shtml#GM-InternalDateCodes

Title: Re: water pump question
Post by: JST69Z28 on March 28, 2024, 03:08:52 PM
Thanks to all for the great feedback. 
Title: Re: water pump question
Post by: GMAD_Van Nuys on March 28, 2024, 03:59:16 PM
I have read that Corvette owners have had good experiences using the water pump rebuilding service below:

https://chevycool.com/

I like that the service posts the cost to rebuild your water pump on their website.  Good luck! - Mark
Title: Re: water pump question
Post by: 169INDY on March 28, 2024, 04:01:43 PM
I Love rebuilding W.P's
1969 Chassis, OVERHAUL manual section: 6K

As a CRG member ,,, PM me if you are not in a hurry & we can discuss off line.

Jim
Title: Re: water pump question
Post by: camaronut on March 28, 2024, 04:45:23 PM
Maybe look at this before you decide to rebuild it yourself.   It can be done - but very carefully. (copy & paste into your browser)

file:///U:/_sys/Redirection/Downloads/WPK%20instructions.pdf
Title: Re: water pump question
Post by: camaronut on March 28, 2024, 11:41:22 PM
Sorry - try this link - better IMO.

https://www.corvettemagazine.com/1956-1982-corvette-water-pump-rebuild/?utm_campaign=179900_C1-C3%20Water%20Pump%20Rebuild&utm_medium=email&utm_source=Zip%20Products%20Inc.&country=&dm_i=6MYT,3UT8,27V0HB,M65M,1
Title: Re: water pump question
Post by: 169INDY on March 29, 2024, 02:13:30 AM
Yes, Step #9 will not work with just a Socket. I have broke two seals using "just a Socket" then fabricated a proper multi-stepped surface Seal driver to push on 3 surfaces simultaneously