Coolant leaks on the 3.4L engines are usually related to the intake leaking or the head gaskets leaking. It's very possible the head gasket is leaking and is pressurizing the cooling system and damaging it leading to the water pump problems but usually the rad & heater core get damaged first. To check for a head gasket leak do a visual check for external leakage or bubbling in the rad or overflow bottle and/or take it to a shop that has a gas analyser or emmision testing machine and see if hydrocarbons are present in the rad or overflow. If hydrocarbons are detected in the cooling system the headgasket is required. Also check for white scum in the oil cap but this is not always a true sign of leakage.
The 2003 Chevrolet Venture coolant capacity is four gallons. The coolant can be mixed 50 percent anti-freeze and 50 percent water.
The defrost is cooing your coolant by circulating the fluids through the heater core. Check the water pump to insure that its pumping and check the radiator for blockages in the fins. Also check for an air bubble that can happen when a thermostat is replaced.
If the pump is not circulating coolant insure that the thermostat is not stuck closed. If the thermostat is ok then the pump will have to be replaced.
You need to check coolant temperature sensor and the water pump.
it could be that you've put too much coolant to percentage of water in
Thermostat possibly installed upside down. Also a possible clogged radiator. we have had the same problems. replaced water pump thermo 3 times flushed sys twice repaired radiator,replaced hoses even left thermo out and still overheating help me too PLEASE!!!!! If you replaced the head gasket, it may not be installed in properly. I.E. coolant passages blocked by gasket. Could be air locked. I had this problem with a 1995 Grand Am. Get yourself a repair manual and follow the entire procedure to bleed all air in the cooling system. Some vehicles have a bleeder valve between the water pump and thermostat housing.
The water pump on a Mercedes ML320 is replaced by draining the coolant, removing the radiator hoses, and unbolting the pump. The gasket can then be replaced and a new pump put in place.
probably the coolant level sensor... Does the temprature gauge go up to hot then down to normal?
If it is just water, it is condensation, and nothing to worry about as this is normal when you first start the engine. If however it is coolant you have a serious problem which is more than likely a blown head gasket or cracked head. If the water smells or taste sweet it is coolant, and not plain water.
Low coolant? System air bound? Hoses collapsing under pressure? Water pump not circulating coolant?
fan clutch?
If it is just water it is condensation and nothing to worry about as this is normal when you first start the engine. If however it is coolant you have a serious problem which is more than likely a blown head gasket or cracked head. If the water smells or taste sweet it is coolant, and not plain water.