Water pump dates
 

Am just finished changing out my water pump for a 250 cu and am wondering if the pump taken off is the original one to the truck, I am second owner. On the front of the pump is cast into pump GM7 and the casting numner on the pump just above it is 3788478. What I assume is a build date for the casting is a circle with an m in the center then G309 another circle with a 1 in the center. Can any decode this for me and do i have the original pump, will save it to be rebuilt at some other time. Any thoughts? This is a great site!!!!.............................Kirby

Re: Water pump dates
 

Kirby, You don't say what year your truck is but the date code G309 would most likley be as follows. G=July 30=day 9=year

Here is an example.

Re: Water pump dates
 

I looks like maybe your 0 might be a 6. In which case the day would be 3 and the year would be 69. Take another look. In most cases the last two digits represent the year.

Re: Water pump dates
 

My truck is a 1966 so this does not look to be the original to the truck.........Thanks for helping with the dates though, useful info.........Cheers...Kirby