CAT0249DHGWR00680 I bought the machine with 2600 hrs. I notice a coolant leak and the coolant reservoir full. The sight glass was empty and filled it back up (this helped me get hot heat back at the heater) and siphoned the reservoir tank down. About 30 hrs later a guy was running it and the machine overheated and coolant all over the engine. The reservoir tank was full again and the sight glass was empty. From standing at the back of the machine the right side of the engine bay was wet but not the right side. I repeated filling the radiator up to the sight glass and drained down the reserve tank. I ran then machine before the second step of filling and draing, up to temperature to try and repeat the occurence but nothing happened. Watching the sight glass coolant would fill up and then lower and fill up and lower. Since then, I have about 5 hrs on the machine. Operating temperature is about 203F and no over heating issues. But I now (not sure if I ever did) do not have cold ac it's about air temp. Lots of things going on here......
I forgot to mention I did have the rad cap tested and it was leaking a little. I bought and new one and replaced it
That sounds as though there is air in the system. Have you tried bleeding it in any way.? Air in the cab heater circuit maybe.? The other possibility is compression entering the cooling system via a failing head gasket. How many psi is it.? it's supposed to be 6-8. The electrically-controlled heater flow valve on these things is not the most reliable thing in the world. Maybe not opening/closing correctly.
They (caterpillar) did not tell me the reading. How do you bleed the system? Cat did mention possible head gasket as well or could be the cap. How do I test the flow valve?
If you bought one from Cat (P/N 036-1865.?) it ought to be right. There is no specific procedure for bleeding the system. I just wondered if you had suspected trapped air somewhere and had tried anything yourself. Attachment shows the location of the valve. Total PITA to get at. First thing would be to ensure it's getting powered up. You should have 12V between wires 124-GN and 200-BK with the key in the ON position. Second would be to check if hot water is flowing through it when you set the cab heater control to the Hot setting once the engine is warmed up.
I had a 249D that had a broken impeller on the water pump.caused issues with pushing antifreeze out and over filling resivor. Also caused the heat not to work because it kept the radiator low.
Also had to replace heater control valve
My 249d had heater control valve issues also... Wasn't hateful to change.