DD60 coolant loss out overflow
I have a 1994 Freightliner FLD120 with a series 60 Detroit in it. The truck is very low millage 550,00 acording to the ECM. I have put about 10,000 miles on this truck since I bought it 2 months ago and have noticed a little problem I see a little coolant leaking out of the overflow every now and then and I will get a check engine light. I add about 2 quarts of coolant and the light goes out. It will still leak a small amount of coolant out of the overflow every once and a while then after about 2,000 miles or so the light will come on and I will add a quart or two of coolant. I replaced the radiator cap and that did not help. The original radiator cap was 10 psi and I just bought a 16 psi cap thinking this might solve the problem. Is this pressure too high??I was worried about a head gasket but the coolant and oil do not look to be cross contaminated. I also do not see any bubbles in the tank while the engine is running. I had the oil analyised 10,000 miles ago when I first bought the Truck and everthing was fine. The truck runs great mantains 180 degrees water temp. I have heard that my truck has a air valve that controls the bunk heater and that this can fail and cause air to pressureize the cooling system and cause a problem like mine. Any advice or suggestions would be welcome
Is this a good question?