Sup all? I need to put a new water pump in my '91 F-150 and I have a brand new pump from my brothers '90 Mustang. So, questoin is are they the same part? they are both 302's. The local autozone tells me that they are different part #'s, but they sure look the same to me. Maby its a different impeller or somthin. I dunno. Anyway, thanks for the help.

 

Truck 302 is prolly non-HO while mustang is HO(Roller block). I think the roller water pump may rotate differently.

 

They don't interchange AFAIK....

One of the problems I ran into was the mustang pump hitting the harmonic balancer.

 

I think the Mustang pump turns a different direction, IIRC. Compare the impellers and see if the vanes face the same way or not.

 

There are two part numbers at AZ for the water pumps - Left and right spin. Just to make things more confusing, the older pumps had the choice of V or serpentine belt pulleys.

Mike

 

The 302/5.0 HO mustang waterpumps up to and including '93 are standard rotation like the truck. In '94-'95 they went to the reverse rotation waterpumps which use a physically different timing cover and pump. The '90 Mustang pump will work. If not, I'm in trouble too 'cuz I just put one on my truck.

 

I thought that most, if not all the serpentine belt drive systems were reverse rotation...

 

I was wrong:

Now I'm confused. My truck has a serpentine belt system. So does that mean it is reverse rotation like the Mustang? Or did trucks use a standard rotation serpentine? The belt takes an s-curve around the pump and balancer pulleys. I hate to pull it off the motor to check but guess I'd better.

Here are some pics I found of the internal differences between the standard and reverse rotation waterpumps: http://www.corral.net/forums/showthr...verse+rotation

 

If the pump turns the opposite direction of the crankshaft, like the s-configuration you describe, it is reverse rotation. My truck has a reverse rotation water pump.