Hi all. My son runs a 2000 Explorer, 4.0 SOHC, 90,000 miles. It overheated recently and ended up with a blown head gasket. Local shop installed a used engine (90 day guarantee). I had new hoses and waterpump installed at that time.
The problem: It seems to be using water still. When I fill the radiator to the top when cold, and overflow bottle to its cold mark, things willl go along fine for a day or so, i.e., normal expansion and draw down of fluid in overflow bottle. Eventually though, when the car is driven under load the fluid level will be down one to two inches in the radiator. I haven't let it run lower than that, so don't now how low it would go. Most recent was a 300 mile trip to college. His fluid level cold, in the radiator, was down about 2 inches (16 ounces fluid approx). The overflow reservior did NOT draw down from its cold level line.
My mechanic says the internal radiator coolant level doesn't matter on these cars, that they are not meant to run full to the neck, that a couple inches low in the radiator would be considered normal. I have a feeling he's feeding me a line - this flies in the face of my experience with every radiator with overflow reservior I have used over the years.
One strange thing re radiator cap. When I could not get the coolant level to steady, I replaced the cap that was on it with a Stant 16lb pressure relief valve cap. With the Stant, when the engine was hot and then shut down, there was some coolant bubbling out from the underside of the cap. I bought another cap without the pressure relief valve and it holds fine. I am wondering if the radiator neck could have warped when the car overheated and not be making a good seal?
What say you? I would love to know if these explorers are normally full to the radiator neck when coolant is cold. Any of you have experience with these radiators? I appreciate any help and thoughts.
BTW, I checked, tightened all hose connections, check for coolant leaks around engine, heater, etc. - all clean.
The problem: It seems to be using water still. When I fill the radiator to the top when cold, and overflow bottle to its cold mark, things willl go along fine for a day or so, i.e., normal expansion and draw down of fluid in overflow bottle. Eventually though, when the car is driven under load the fluid level will be down one to two inches in the radiator. I haven't let it run lower than that, so don't now how low it would go. Most recent was a 300 mile trip to college. His fluid level cold, in the radiator, was down about 2 inches (16 ounces fluid approx). The overflow reservior did NOT draw down from its cold level line.
My mechanic says the internal radiator coolant level doesn't matter on these cars, that they are not meant to run full to the neck, that a couple inches low in the radiator would be considered normal. I have a feeling he's feeding me a line - this flies in the face of my experience with every radiator with overflow reservior I have used over the years.
One strange thing re radiator cap. When I could not get the coolant level to steady, I replaced the cap that was on it with a Stant 16lb pressure relief valve cap. With the Stant, when the engine was hot and then shut down, there was some coolant bubbling out from the underside of the cap. I bought another cap without the pressure relief valve and it holds fine. I am wondering if the radiator neck could have warped when the car overheated and not be making a good seal?
What say you? I would love to know if these explorers are normally full to the radiator neck when coolant is cold. Any of you have experience with these radiators? I appreciate any help and thoughts.
BTW, I checked, tightened all hose connections, check for coolant leaks around engine, heater, etc. - all clean.
