6.0/4L80e swap running hot!

[pl4yboy]

I would check for air bubbles in the system...

[ThunderBolt]

I would check for air bubbles in the system...

I pulled the crossover tube off while running and air came out.. I put it back on but still feel like there's air in the system. A buddy that works at GM said that the best way to get air out is to vacuum the system but that requires a special tool or getting the dealership to do it. I think i might get a pvc pipe and install it in the middle of the crossover tube (since it's the highest point of the system) and make a pressure release valve into the pvc pipe.. I would keep the valve open until coolant is steady streaming out.

Anybody think this would work? Or know a better way to get air out?

[pl4yboy]

I pulled the crossover tube off while running and air came out.. I put it back on but still feel like there's air in the system. A buddy that works at GM said that the best way to get air out is to vacuum the system but that requires a special tool or getting the dealership to do it. I think i might get a pvc pipe and install it in the middle of the crossover tube (since it's the highest point of the system) and make a pressure release valve into the pvc pipe.. I would keep the valve open until coolant is steady streaming out.

Anybody think this would work? Or know a better way to get air out?

Fill it to the top with coolant with the vehicle running. The air bubble will likely end up in the crossover. Squeeze the crossover in a pumping manner until the bubble is pumped out. Keep filling the system as it runs down. EVENTUALLY, the bubble will come out.

[RedHeartbeat]

park it on a hill, engine off, with the front end higher than the rear, take the air bleed hose off, remove the upper radiator hose from the radiator, pour water into the hose until a steady stream of coolant comes out of the air bleed hose fitting on the engine side. Reconnect everything.

[ThunderBolt]

Fill it to the top with coolant with the vehicle running. The air bubble will likely end up in the crossover. Squeeze the crossover in a pumping manner until the bubble is pumped out. Keep filling the system as it runs down. EVENTUALLY, the bubble will come out.

park it on a hill, engine off, with the front end higher than the rear, take the air bleed hose off, remove the upper radiator hose from the radiator, pour water into the hose until a steady stream of coolant comes out of the air bleed hose fitting on the engine side. Reconnect everything.

I tried both of these methods but it's still overheating. I even found a good article about the GM coolant fill procedures which RedHeartbeat was describing.. We've had complaints of overheating on some late model GM truck engines; any clue why this is happening?: Engine Builder

I'm going to take the water pump off and check it out; something tells me there is something blocking my water passages not letting it circulate properly.

[ThunderBolt]

I just took the water pump off to inspect it and everything looked okay, and there was nothing blocking the water passages. Just to be on the safe side I put the water pump off of the 5.3 on because I knew that it worked but still no luck. This truck just won't stay cool!!