Something is definitely wrong with my truck, firstly it blows no heat, the overflow tank is about to overflow, there is yellow sludge under over flow cap, the rad is empty and when I first start it in the morning it starts to smoke a bit from somewhere on the drivers side for a minute or too( I live in Saskatchewan and right now it’s super cold ) also when I shut the truck off you can hear the sound of coolant running, kinda like a sloshing sound, other times I’ll hear bubbles popping or a blurbing sound coming from under the dash. . . . Took to a shop to have a pressure test done and they said there was a minimal leak from water pump gasket and that it only dropped one pound of pressure in a half hour. . . It was money wasted because they couldn’t tell me what is going on with the truck, told me everything seemed to be good. . . Obviously it’s not good. . Please help. . .
The sounds of bubbles are from the low coolant level boiling. The radiator should be kept full. Radiator empty is indication of leak. Leak must be repaired for cooling system to function properly. No heat is also from no coolant in the system. Suggest replacing the thermostat and radiator cap at the same time as you replace the water pump and coolant. Then pressure test the cooling system again. Pay close attention to intake manifold gaskets and freeze plugs for any signs of leaks. If you notice the coolant level going down and there are no external leaks, look for an internal one if you are loosing pressure. This could be in the form of a failing head gasket or intake gasket. You will notice WHITE smoke and potentially a fouling plug or two and a running rough engine at start up. Looked up the water pump for the 5.7L engine. It doesn’t look too bad a price and includes free shipping.
WATER PUMP ASSEMBLY R&R
REMOVAL
- Remove the air cleaner assembly.
- Remove the air cleaner outlet resonator duct.
- Drain the cooling system.
- Remove the cooling fan.
- Remove the drive belt.
- Reposition the radiator outlet hose clamps at the surge tank and water pump.
- Remove the radiator outlet hose from the surge tank.
- Remove the radiator outlet hose from the water pump.
- Reposition the water pump inlet hose clamps.
- Remove the water pump inlet hose.
- Using fan clutch remover and installer tool No. J-41240, or equivalent to hold the water pump pulley, remove the water pump pulley bolts, Fig. 1.
- Remove the water pump bolts, Fig. 2.
- Remove the water pump, Fig. 2.
- Remove and discard the water pump gaskets.
- Clean and inspect the water pump, as required.
INSTALLATION
After assembly, the hose clamp tangs (water pump end) must point forward and the upper tang should be level with the outside diameter of the water pump inlet hose. - If using the original fasteners, apply sealant GM part No. 12346004, or equivalent to the threads of the water pump bolts.
- Install NEW water pump gaskets and the water pump.
- Install the water pump bolts. Torque the water pump bolts to 33 ft. lbs.
- Using fan clutch remover and installer tool No. J-41240, or equivalent to hold the water pump pulley, install the water pump pulley bolts. Torque the water pump pulley bolts to 18 ft. lbs.
- Install the water pump inlet hose.
- Position the water pump inlet hose clamps.
- Install the radiator outlet hose to the water pump.
- Install the radiator outlet hose to the surge tank.
- Position the radiator outlet hose clamps at the surge tank and water pump.
- Install the drive belt.
- Install the cooling fan.
- Install the air cleaner outlet resonator duct.
- Install the air cleaner assembly.
- Fill the cooling system.
- Inspect the cooling system for leaks.
