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Crank driven raw water pump

Chris Rohde

Chris Rohde

Regular Contributor
I need to rebuild or replace my raw water pump as it is leaking at the weap hole. I would much rather replace the pump with a crankshaft driven pump. I see plenty for Chevy motors. Anyone know the right one for a Ford 5.8?

1995 5.8FsiPHUCCE.

Thanks!!
 
Take a look at the Johnson F5B-9.

If your harmonic balancer is threaded with the same 3 bolt pattern as the GM engines are, the F5B-9 should work.

Even if this should require a bit of modification, it's well worth doing.

The belt driven pumps do not lend themselves to an easy impeller replacement ........ often resulting in deferred maintenance.

You will have no more issues with the Johnson crankshaft seawater pump!

4 screws, and you can easily remove the impeller for winter lay up.




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Unfortunately, I have the 4 bolt harmonic balancer. Quite the deep pully on there also. Those outlets are going to need to be slightly over 3" out from the mounting plate in order to clear the pully. I would hope I would not need to add some sort of plate to bring the pump out a bit. What type of modification am I looking at to make this work? I'm assuming drilling a 4th hole. What about a bracket to keep it from spinning. Am I going to be modifying a GM bracket?
 
I would leave the Belt driven pump and just leave the belt slightly loose. I have found that over tightening of the belt wrecks these pumps prematurely.

Tighten the belt just enough that it does not slip.
 
I'm going to stick with the belt driven pump for now. I just don't want to go through a ton of mods to make the crank driven one work. If I had the 3 bolt, and a shallower pully, I would do it. But I think I'm getting into drilling the new pump, making some sort of base plate to bring the pump further out, and probably fabricating a bracket. I've ordered a rebuilt pump, and will send in my old one as a core. Was under $200 and everything will bolt right up, which is what I need right now. Thanks for all the suggestions guys. Also, I will take the recommendation on the belt tension and make sure I don't over-tighten it.
 
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