Hey Folks,

The Water Pump flange on the R53 has two identical o-rings, one against the block and one against the WP outlet. Are the factory ones any kind of special material? Or just standard Buna / nitrile?

Also, why do people replace the flange? What happens to the old one?

Thanks!

 

I have no idea about the material. But from doing a WP install I would say buy a stocker. You dont want the gasket to roll out of the groove on the water pump when you push it into the connector. In my case
I bought a new connector since the flange on mine had corrosion on it and looked like it was leaking onto the block (it was rusty underneath it). Think the corrosion on them is a common problem.

 

I know this is old but I was digging around and spoke to the parts rep from advanced and they cross referenced the oring for the flange to block and it’s number is 35965