Hi I’m having an issue where my 247b3 won’t blow heat. I took it out today and ran it to warm it up and then I lifted the cab and felt the two lines coming out of the heater core and they were both cold. So I traced them back to the engine and the hose that comes out of the regulator where the thermostat is was hot near the housing and then the line stays warm for about a foot and then it’s cold. Does this mean my thermostat is bad or some sensor? I haven’t had any issues with it overheating or anything though. Also the heat worked great in it last winter so not sure what’s going on. I would appreciate any help. Also the serial number is TSL01509 if that helps. Thanks
Coolant level correct? Fan belt present? Water pump actually turning? Heater knob not stripped?
I would suspect the heat regulator control for the cab. It’s not letting coolant flow.
See if this thread gives you any ideas............ HeavyEquipmentForums
The coolant level is good, it’s about 1/2 on the overflow tank and I have a pencil line on the tank to mark the level when it’s cold and it’s still at that level and I haven’t had to add any coolant all year. The fan belt is good I had a new one put on this spring and it’s tight. For the heater knob in cab it does feel like it working but there’s no way for me to tell for sure with out taking off the hose and looking inside to visually see if the valve is turning. As for the water pump I believe it’s working, the two main radiator hoses both get hot when running so I think that would be a good indicator that the water pump is working. I’m not a pro though so correct me if I’m wrong on any of my reasoning with these or if there’s something else I should check?
See the link I posted above. There is an electrically-operated valve that controls the heat on those machines.
I did look at that but on my schematic it is #24 which is part number 231-8126 which appears to be a manual valve that connects to the control knob in the cab
Sorry I thought all those had electrically-controlled heat valves.
Mechanical valves fail as well. Movement of the stem doesn’t always translate into movement of the actual flap (for lack of a more technical term)
Ya that’s true but even if the mechanical valve has failed and the flap is stuck in the closed position wouldn’t the heater core inlet line at least be hot up until it reaches that valve? The problem I’m having is where the inlet line gets cold after like a foot of leaving the thermostat housing which makes me think that the problem is before it even gets to the that valve and heater core.
If the valve is closed no water will move through the heater lines and they will not get hot, apart from maybe the first 6” or so from the engine block which may get warm from conduction.
If the coolant can’t flow it will only get hot so far from the motor. Sorry Nige posted as I was typing.
Ok that does makes sense. I will have to do some digging then into the valve and I’ll report back what I find. Thank you both
Finally got around to looking into it and sure enough it was the mixer valve. The knob turned but the valve inside was stuck closed. I ordered a new one and installed it and now I have heat again. I really appreciate the help, thanks.
Nothing like a warm cab this time of year.......
Always good to put the radiator level and check the level of antifreeze with the cap off. Because if you ever get a small leak in the system, when it cools and tries to suck back from the reservoir it will suck in air from outside instead sometimes and your coolant level overflow tank wont come down. Many folks have been horrified to look down into a rad and find it half empty with the overflow tank still full.. Hope this helps for if it ever happens to you. Simon