Chevy Water-Pump

nick c · Apr 8, 2007

Another great stupid question from me...hoping some of you more 'smarter' people out there know the answer. :hi:

Did Chevy make water pumps that go counter-clockwise and clockwise for the mid-80's 305s? I'm running a 305 in my truck and have the WORST over heating issues, its the plague I tell you. I've tried everything to cure this, about the only thing I can do that seems to help is run it with out a thermostat.

But I am wondering, maybe I've got a wrong rotation water pump on there. And its just causing turbulance rather then actaully pumping water like it should.

Not sure....

Boonie Buster · Apr 8, 2007

clogged radiator???

nick c · Apr 8, 2007

nope...thats been flushed several times now. and the radiator is in the bed of the truck, with a Tuarus fan on it, running copper pipe from the engine back under the truck to the radiator.

Seems the only cure for this so far has been to pull the thermostat. Once I pull the thermostat I have no issues, and the water flows freely and I've checked it 3 times now, the thermostat does open completly.

I was thinking, maybe with the increased volume of the cooling system the water pump is having a hard time pushing all the water. But not sure thats the issue. And really wondering if I got the wrong rotation pump on there.

Anyone got a good idea of how i could find out?

Binder · Apr 8, 2007

Yes there two different rotations.

Boonie Buster · Apr 8, 2007

Binder said:
Yes there two different rotations.

would the difference be from a v-belt setup and a serpentine setup??? or are there just weird years in there???

Zoediak · Apr 8, 2007

yes the difference is with the serpentine belt systems...

when they introduced the serpentine systems in the mid to late 80's the routing of the belt required a reverse rotation waterpump... the pumps look identical except the impeller blades are turned the opposite direction.

I hope this helps...

as a good rule of thumb, when you replace the waterpump, it is a good idea to replace the thermostat and flush the ratiator at the sametime.

nick c · Apr 8, 2007

well my system is a standard v-belt system, the motor was pulled from an 83 Monte Carlo. But I replaced the water pump and it didn't come with a pulley on it, so I wonder if they gave me a reverse rotation pump on accident.

Ill have to pop the cover off the back-side and see what the impellar looks like.

Pook · Apr 8, 2007

Cool learn something new everday. Now I got to file this info somewhere in my brain. It'll come in handy if my old tow rig ever needs a waterpump.

crash2 · Apr 8, 2007

Zoediak said:
yes the difference is with the serpentine belt systems...

when they introduced the serpentine systems in the mid to late 80's the routing of the belt required a reverse rotation waterpump... the pumps look identical except the impeller blades are turned the opposite direction.

I hope this helps...

as a good rule of thumb, when you replace the waterpump, it is a good idea to replace the thermostat and flush the ratiator at the sametime.

yup yup (did marcus tell ya,lol)

Now the wuestion lies--do thjey make a reverse rotation shorty pump :;

Zoediak · Apr 8, 2007

crash said:
yup yup (did marcus tell ya,lol)

Now the wuestion lies--do thjey make a reverse rotation shorty pump :;

lol, I actually ran into this problem with a friend back in the 80's when we had to change his mom's waterpump on her truck....

since I was working in the shop at a local parts store back then, they made me troubleshoot thier screwup.

as for the shorty pump, I don't remember ever seeing or using a reverse in any of my show cars. All of the serpentine belt conversions I have done never required the pump to be changed.... so, I may be wrong but I don't think it is on the short style... unless it is an aftermarket purchase..

nick c · Apr 8, 2007

well I pulled the pump this afternoon, and took it down to schmucks. And against the will of the guy at the counter I proceeded to remove the backing plate off the one they had on the shelf. Same style prop (which to me looks ass-backwards). I will try and post a picture later tonight or tomorrow (gotta go to the girl friends for dinner with her folks).

So I went ahead and flushed the motor since the pump was off, and then flushed out the radiator, and I will put it all back together. Not sure what the deal is.