I have an L2550D that runs hot. The weird thing is when I'm going up a hill, the temp gauge shows it's starting to run cooler. Have changed the thermostat, belt, and just had the radiator taken apart and cleaned. The tractor has never "boiled over." I've contacted several mechanics and no one has ever heard of a tractor running cooler while going up hill. When backing up hill, still runs hot. Must go up hill forward for the cooling to occur. No excess play in the water pump and no fluid is coming out of the weep hole. I think I'll change the thermostat again in case I got the wrong one the first time. Any suggestions?
L2550D runs hot
- Thread starter maxok
- Start date
Tapeworm
New member
Equipment
95 B1750HST; Allied Loader; Wallenstein BXM32 Chipper/Shredder; Agrotrend Blower
I don't suspect the water pump at this point. No abnormal noise is coming from the pump and it doesn't have any endplay. Additionally, no fluid is coming out of the weep hole. As for the gage, it registers hotter than it should. I reads about 3/4 of the way to the red, considerably higher than the "normal" notch. When going up hill in forward, the gage starts to creep down to normal but never reaches it. When first warming up, gage seems to operate normally. I've read where certain models the sending unit gives a false hot reading due to it's close proximity to the exhaust manifold. This sending unit is towards the back of the head next to the injectors. The needle gage shows hotter than it should be and just sits there until I run it at idle or work it going up hill. No wandering of the gage.
Hummm so thermostat has been changed, radiator has been overhauled. Ok next question, has it always done this or did it start recently? Honestly it sounds like the thermostat is of a higher temperature than the normal notch on your gauge or your gauge has gone gullible on you.
In that vein get a thermometer capable of at least 120C, a candy thermometer would work nicely. Leave the thermostat out and pull the fan belt so the water pump is disabled and then remove the upper radiator hose. It might be a good idea to warm it up before hand but get the motor up to operating temperature and compare the gauge to your thermometer. You can test your thermostat in a pot of water on the stove using your thermometer.
Another remote possibility that occurred to me is the water pump shaft may have cracked at the impeller though I consider that highly unlikely.
Matt
In that vein get a thermometer capable of at least 120C, a candy thermometer would work nicely. Leave the thermostat out and pull the fan belt so the water pump is disabled and then remove the upper radiator hose. It might be a good idea to warm it up before hand but get the motor up to operating temperature and compare the gauge to your thermometer. You can test your thermostat in a pot of water on the stove using your thermometer.
Another remote possibility that occurred to me is the water pump shaft may have cracked at the impeller though I consider that highly unlikely.
Matt
Bizarre symptoms call for bizarre diagnosis. Leaky head gasket maybe. Lets a hot gas bubble build up around the temperature sensor; bubble breaks away and flows up-hill away from the sensor when inclined. I guess you wouldn't have an old fashioned exhaust gas sniffer to put in the radiator fill neck and sniff for gases. . . . Do this cold, fill the radiator right up into the neck and leave the cap off, start it and watch for bubbles coming up as it warms up, it will over flow a little bit but see if it continuously emits bubbles out the filler neck.
This is truly a wild axed guess on my part but what else would act like that going uphill when more engine power is pouring on?
....I'll blame this one on my cold medicine.
This is truly a wild axed guess on my part but what else would act like that going uphill when more engine power is pouring on?
....I'll blame this one on my cold medicine.
Ok, thanks for the ideas. I did get another thermostat and will put in in today. While I've got it apart I'll check the temp. I did run it without the radiator cap after reinstalling the radiator and no bubbles were seen. I put new coolant in 50/50 mix. Old coolant was a year or two old but it looked clean also. No oil in the radiator, no water in the oil. No water or oil leaks anywhere on the engine. No rough running when starting cold which I would expect with a bad head gasket. One thing I did notice when I reinstalled the radiator was while bringing it up to operating temperature the bottom half of the upper radiator hose was cool and the top was warm. After I got it up to what has been its operating temperature the top hose was completely hot but the lower radiator hose was cool. Also, more pressure was felt on the upper hose when compared to the lower hose. As for the bypass hose on the right side of the engine, no pressure was felt (the hose was easily compressed). This is what made me wonder if my thermostat was malfunctioning or even the wrong temperature. Asked the Kubota dealer what the thermostat temperature was supposed to be and they had no idea which I though was weird. Went ahead and spent $30 on a $6 part so it would be supposedly right. No temp is stamped on the thermostat but a 99 is written on the edge. Does anyone know what the thermostat temperature is supposed to be? By the way, the last thermostat I put in I also bought from Kubota.
i just bought a thermostat from a kubota dealer it had 82 no it i dont know if that is a celucis # or what and i have a l2550 mine was running cold i would take a close look at the gauge myself