Iron@Dirt
Senior Member
dont know about d21 but our d39 heated up right away. found the torque convertor housing full of oil. the ring gear really heats things up. torque convertor seals were leaking trans oil into housing.
How is the hydraulic cooler is it clean ? Because that will make temp go up .Whats your email ?I will email the service manual so you have it .I'm running straight water right now, still flushing it out some. The belt is tight, It was a little loose before but its tight now with no improvement. Fan blows outward. Radiator is clean on the outside. Seems clean enough on the inside, when I drain it, the cores drain too, no visible crud. With the cap off when its hot, the pump seems to be moving a lot of water. I don't know what normal is but its sloshing around a lot.
Temp wise, my gauge is faded so I don't know exactly, but its past the green into the white. Sometimes at the very edge of the green into the hot zone. It stays up there. I've not had it boil over yet but its hot. Higher RPMs drop the temp down a little but once its under a load it gets hot again. Not to the point of pegging the gauge but I don't feel comfortable running it.
I need to get an infrared thermometer and see what everything is actually at. I hate to spend the time and money on a water pump without knowing if thats actually the problem or not.
Cleaning out the rubbish from the bottom will help , won't heat the dozer up but won't let it cool either . If you have the damper out I wouldn't mind seeing some photos of it close enough to see how it works .Just got my service manual emailed from Tool King. You are correct, they call it a damper case and it should contain 1.5 liters of oil. I'll try to pickup a temp gun and go from there.
Its clean as a pin on the outside. The inside looks pretty good to me. There is a little rust on the filler neck but everything else is clean and if I drain it, the cores empty as fast as the rest of it. The coolant that was in it was pretty crudy. It took several flushes to get clear water out of it.I would be more inclined to suspect a dirty radiator, either external and/or internal.
I can't help with the wiring diagram, but whenever I've had a piece of older machinery with overheating concerns and there were no obvious leaks or failed parts (water pump, thermostat, radiator, rad cap) I've had good luck doing a couple flushes with radiator cleaner from the auto parts store. Read the bottle of the radiator flush product to find out how much to use for the machine's cooling system capacity and mix it on the strong side. It's amazing what kind of gunk this can remove. I drain out the coolant, fill up with just water and the radiator flush product, run it good and hot for a while, then let it sit overnight. Next day drain the system then repeat a second time with new water, rad flush, and a good hot run. Drain, rinse it out with clean water to remove any traces of the flush, then refill with new coolant with Red Line Water Wetter added. This has never failed to work for me.Well the saga continues... Got the new water pump put on, pulled the radiator and gave it a thorough washout, got everything put back together, and it still runs a little hot but it never gets to boiling over. Every once in a while the temp gauge will spike then cool back down (which might be a symptom of my next problem)..........