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Old 07-05-2012, 12:00 AM
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Originally Posted by pacman350 View Post
a buddy of mines has a 89 camaro with a rebuilt sbc motor out if a 94 chevy truck. i dont know the specs on the motor but he can not run it with a thermostat because it will not open and he has tried 6 or 7. without a t-stat in it it still runs really worm the motor has the original serpentine belt setup. the antifreeze seems to flow out the fines in the radiator the right direction but if he installs a t-stat. we thought i they may have used the wrong water pump because it do use a reverse flow water pump but with the rad cap off it looks to be flowing in the right direction out the fines. he as a summit or griffin 2 row rad with a derale dual fan set up. the other day when the temp hit 104 down hear in georgia he couldnt drive it engine temp got up to 245 with both fans on at highway speed.
It uses a reverse rotation (CCW as viewed from the front of the engine) water pump, not reverse flow. Same direction of water flow, but the pump turns "backwards" because of the serpentine belt.

A standard (CW) rotation pump will still pump water if turned CCW, just not efficiently, and the loss of efficiency is increased w/the speed the pump is turning.

I would strongly advise you to be positive the correct pump is on the engine before chasing your tail.

...coolant isn't staying in the radiator long enough for it to do it's job...
Using the same logic, the coolant would also be passing through the engine too fast to pick up heat in the first place, but the coolant is at 245 F (at least by his gauge).

From here (in part):

A common misconception is that if coolant flows too quickly through the system, that it will not have time to cool properly. However the cooling system is a closed loop, so if you are keeping the coolant in the radiator longer to allow it to cool, you are also allowing it to stay in the engine longer, which increases coolant temperatures. Coolant in the engine will actually boil away from critical heat areas within the cooling system if not forced through the cooling system at a sufficiently high velocity. This situation is a common cause of so-called "hot spots", which can lead to failures.
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