Water pump question - turns hard...

[klaird]

I just re-installed the water pump on my rebuild engine and I have a general water pump question. I am noticing that the water pump shaft is a lot harder to spin by hand after being installed. Is this normal? Kind of like pre-load on pinion? I am concerned it takes too much "power" to spin it. I can barely turn it by hand and in fact I needed a pipe wrench to get it started. I do not have the fan installed, just grabbing the 4 little fan bolts and spinning it that way? Is there a way to test for spin "tension"? In other words, how much torque ft lbs should it take to spin the water pump shaft? If it makes a difference, engine is 3.8 L 231 V6 1984 .

 

[bill]

Pump should turn easily...without a lot of effort. Sounds like you have something blocking it or its binding on the timing cover. Its possible that the impeller was not pressed all the way onto the shaft and it's now hitting the timing cover. I'd pull it back off...take it back to the store and get another one...tell them you need some new sealant and they should throw that in for free for your trouble.

 

[klaird]

It's not a new one. It's one I pulled of an 85 that was showing no signs of leakage. I'll pull it off and now I'm wondering what the differences are between the 84 nad 85 water pumps and timing covers. Hmmmm.

 

[klaird]

Pulled it off and sure enough the water pump was rubbing the timing cover. Must be the 85 is "deeper" than the 84 timing cover. Or else there is an "extra thick" gasket that can be used...Odd