View Full Version : Left Hand rotation water pump ?

08-18-2005, 09:02 PM
Need to replace the water pump in my 79 with 351. Based on the part numbers it reflects a left hand rotation. Pep Boys has water pump on stock for like $50. Is there a difference in water pumps between left hand rotation and right hand rotation engine? Do I need a "marine" water pump?

08-18-2005, 10:16 PM
In some cases, the shaft seal on the marine pumps is more durable since it won't be pumping water/coolant mix, which acts as a lubricant. There was a big problem with the GM pumps in '98 and GM denied that there was a problem with them. Once MC and Indmar went to Sierra for the replacement pumps, the problem disappeared and GM honored the warranty claims.

dog paw
08-18-2005, 10:16 PM
Yes the impeller in the pump is "backwards" for lack of a better way to put it. It will not circulate water well spinning the wrong direction. We had a car come in the shop years ago with a marine water pump the customer had put on. He had pulled his hair out trying to figure out why it was overheating :confused:

08-18-2005, 10:49 PM
by looking at my waterpump, it is an automotive. it has ports for a heater coil. I have a '85 351, could this be a problem? Should be standard rotation right?

08-18-2005, 11:50 PM