SBC Water Pump Rotation (1 Viewer)

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Mar 9, 2006
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Does anyone know how to identify a SBC water pump? How do I determine if it is designed for CCW or CW rotation? Can I look at the impeller? I can't keep the 383 stroker in my FJ40 cool enough and I am trying to eliminate all of the possibilites...
 
i'd say 9 chances outta 10 its standard rotation.. . but i think pretty much anything that used a serpentine belt has a chance of it being a revers rotational water pump
 
Is the flange on the water pump different for serpentine pulleys? I don't know what the pump came out of - I didn't build the engine. Who knows where the PO got it. I guess I could just order a new pump to make sure but why spend the money.
 
In the past I've had to remove the rear cover to make a positive Id... the one in the pic is cw impeller.....
E_Impeller3.jpg
 
I'm curious on your setup with the 383 , so how about sharing some more details:
-What radiator are you running?
-Thermostat?
-What size and kind of fan, mechanical solid, mechanical clutch, or electric fan?
-Using a fan shroud?
-Transmission manual or auto?
-Carburation or FI?
-How much timing?
-Cam?
-Estimated HP of the engine?

And, what type of driving makes it run hot? Stop n Go?, Freeway?, Trail?
How do you know its really running hot? Temp gauge readings? Pushing water out overflow? Pinging? Run-on with ignition off?
 
Thanks for the pic grant. My impeller is not that agressive, that's probably a high flow one right? The blades on my are curved the opposite way than the one in your pic. Maybe I do have a reverse flow one.

my64: I'm not running a serpentine setup.

miker:

-What radiator are you running?

I took the stock radiator and put a 2" taller + 4 row core in it. It runs fine in cool weather - 180 deg. consistently. In the summer it can get up to 220. I'm in the process of putting a radiator out of a 78 cadillac in it. It has 15% more surface area, but it's only a 3 row. I'm hoping that the extra 15% in surface area is more efficient than the 25% more of tubes/core in my old one. The cadillac radiator is in all kinds of cars with motors from 305s to 6.6L camaros. Both radiators are brass/copper construction.

-Thermostat?

180 deg.

-What size and kind of fan, mechanical solid, mechanical clutch, or electric fan?

Mechanical solid.

-Using a fan shroud?

Yes (but it was designed for the stock radiator height - it doesn't cover the extra 2" of core that I added.

-Transmission manual or auto?

Auto TH350

-Carburation or FI?

Carb

-How much timing?

About 7 deg (used to be 12, lowering it helped but not enough)

-Cam?

I'm not sure.

-Estimated HP of the engine?

I think 350 is probably a modest guess.

And, what type of driving makes it run hot? Stop n Go?, Freeway?, Trail?

It only runs hot when the ambient temperature is like 95+. It's kind of weird. It will run hot at idle. But when I get to cruising speed, say 30 - 40 mph it starts to cool back down. Then when I get on the freeway it climbs back up. I have plenty of air flow I just think it needs a bigger radiator.

How do you know its really running hot? Temp gauge readings? Pushing water out overflow? Pinging? Run-on with ignition off?

I think my gauge is pretty accurate. It stays right on 180 in cold weather. Unless it is inaccurate up past 200. It also starts to ping at about 205 under a load - even with the timing down at 7. It hasn't boiled over yet so that's good but I would really like to keep it down closer to 180.
 
Wow, good info.

Fan:
From what you are describing, I think part of the problem is airflow. I'd suggest trying a clutch style fan, a big one, like a cadillac 7 blade along with a heavy duty clutch. Making sure the shroud fits correctly to the fan should also help.


Radiator:
I think you are on the right track with more surface area of radiator or a more efficient one.

In my fj40 with 383 and th400, I had a 3 row copper/brass rad with 46 rows (46x3 tubes) which did a decent job of keeping it cool. I had no problems on the trail unless working it very hard, or unless I was on the freeway pulling a long grade. Still, I could keep it under 220 and it generally ran 190 to 210. When this rad sprung a leak, I bought a 4 row copper brass thinking it would be better - wrong. It was much worse. The 4 row had more tubes, about 160, but less rows (40x4). I believe this made it less efficient. With the 4 row radiator, the engine would regularly get to 225 on the trail and on the freeway even when on flat ground.

I've since installed a BeCool and it works a bit better than the old 3 row I had. I can still get the engine to 220 but I've got to be working it pretty hard. It generally runs from 180 to 195 with a 180 thermostat. Even pulling a long steep grade at freeway speeds, it generally doesn't get above 215.

Timing:
Setting the initial timing is just part of the timing picture. You should also check mechanical and vacuum advances and make sure total timing (initial+mech+vacuum) does not exceed 35 degrees. Its possible to have more than 35 degrees of advance from a mis-adjusted vacuum diaphram or malfunctioning/incorrect mechanical advance weights/springs. Add this to the initial and under load, you could have 40, 50, 60 or more degrees of advance. I learned this the hard way. If the engine is pinging, I'd suggest fixing that first or at least looking for obvious causes like total timing.
 

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