2000 surburban 5.3 coolant flow question?

I do not have coolant flow. Changed Waterpump and Thermostat 2 times, hoses, new radiator and even clutch fan. I even cut out thermostat all together just to make sure that wasnt causing any flow problems. I flushed out heater core and hoses.

I’m thinking i have a block in engine not allowing flow. only thing left i can think of… So currently i have water pump removed and my question is: There is 4 open ports, 2 on each side for which the waterpump covers and pumps coolant through. Is the coolant pumped in 2 holes on one side and then comes out other 2 entry ports on other side after flowing through engine block??? I tried to flush with waterhose, but can only get water to come out on same side of the 2 ports. NOTE: The port are ones square and other circle bore, one on each side. Flushing through square port and water comes out circle port.

any helpful ideals, what to do will help. Does coolant flow from one side to other?



Water comes into the pump through the lower radiator hose and is pumped into the block where it travels up into the heads, is combined in the intake manifold and heads back into the radiator through the upper radiator hose, restricted by the thermostat… With the thermostat removed, a surprising amount of water will be pumped…

In a V block, the two cylinder banks may be separate, as are the heads…The cooling water is combined in the intake manifold as it exits the heads…The two ports may direct water to the front and rear of the block…Water injected in these ports with a hose should eventually exit at the thermostat housing…

You might try back flushing as long as you have water pump removed, try and get pressure flow from the upper radiator hose, with the pump removed I think the thermostat will not come into play. Is the thermostat in line with the lower hose or upper hose from the water pump. If it is the upper circuit pull the themostat again and backflush.

Edit it appears the thermostat is just after the lower radiator hose if I believe youtube https://www.youtube.com/watch?v=k6K4ztF0kgM

Could the water pump be wrong and designed to turn the other direction? I know with some GM motors you have to be careful about that. It has to do with some running v-belts and others running serpentine belts. They dpin the water pumps in opposite directions.

Yes i was wondering that as well… possible to turn backwards? wish i knew answer. I do know the belt will only go one way to turn it, But im still puzzled if the water flow goes through one side of engine block 2 holes and comes out other side with 2 holes of engine block? I never flushed a engine block before and dont want to put new water pump on untill i know. The water pump itself is HUGE. like 12- 14 inches long.

This engine family always had a serpentine belt, and the water pump gets driven by the flat side of the belt. So it turns counterclockwise

There is no choice to make, as far as rotation of the water pump

At least in this instance

With the pump removed, when you force water into one side, it can fill that side, go up into the head, the intake manifold, and down into the other side of the block where it will run out the two holes that would normally be inlet ports…