Hi all,

1991 GMC, V1500, 4wd, Auto, 350, Serpentine (1 Belt) system

Okay, going to replace my water pump and while buying the water pump at the parts shop the guy asks if I have a normal or reverse flow system? I believe I have figured out what I have but would love to hear from someone more knowledgable on how to tell the difference...

Any and all input is appreciated!

Thanks,
Rick

Your engine is the normal system, reverse flow was used in high perf eng like the LT-1



jeff

Did they ask if you have reverse flow or reverse rotation? They are two very different things.

When GM went with a serpentine belt, the direction of the pump is different that a conventional belt.

For your 91, you need a long-style pump with reverse rotation.

//2000CAYukon