I will try to make this brief. Basically there was a leak that was coming from my waterpump in my 05 equinox. We decided to replace it. There are 5 holes in the pump and 4 of them measure out to 8mm and one of them is 12mm. So when I get the new pumps I’ve bought a couple now. The screw holes are all the same size 8mm. And there’s isn’t an individual hole that measures too 12mm. So when I got to install the one bolt will not fit in the last hole. I was told it was because of aftermarket parts. So I call the Chevy dealership to find the original part number (19179031) and it’s been discontinued. I have no clue if I can drill the hole I need in the water pump? Or if I need to find this part? What should I do?

 

I found this on Amazon. It says it is a replacement for 19179031. If all else fails, I would drill out the one hole if it looks like there is enough metal there to keep it strong.

 

ACDELCO 252721
Don't waste your time with estraz parts.

 

Does it look like the pump has been replaced before? From the factory the bolts should all be the same size.

The larger bolt could have been a “fix” for a previous repair in which a bolt broke or the threads stripped and it was drilled/tapped for a larger bolt in a pinch.