[gowiththegreen]

today while cutting my engine temp alert went off. i figured my radiator needed to be blown out, so i did so. problem fixed, than about 2 hours later the same thing again. i blew it out again , but right afterwards the motor got hot again. i then called my local deere dealer and they said it could be a thermostat. i installed the thermostat and it did not fix the problem. now i am wondering if it could be the sending unit or the electrical plug for it. also, when the temp gauge was showing HOT, i could go back and put my hand on the radiator cap. it sure didnt seem too hot for "overheating" . anyways, i am gonna try a new sending unit in the morning, but if anyone else has any ideas please let me know.

thanks

 

[dwthunter]

I fought my 9600 all wheat harvest as well. replaced thermostat and sending unit. I sent it to the shop for some work before corn and my radiator was all limed up. Not sure if you can use ph strips to check the coolant or if you have to drain radiator and inspect through the bottom hose fitting. hope this helps

 

[ststech]

water pump is a possiblity, i have changed a few

 

[ccjersey]

A temp gun will help to quickly diagnose an "overheating" problem like that. If you don't have access to one, next time it goes off check (feel) the temperature of the water outlet area where the thermostat is located as well as the inlet and outlet connections of the radiator.

I would normally expect a failed sending unit or gauge to stay failed, not be intermittent. A wire or connection problem could be either way. You need to see what's hot and what's not before you start tracing down stuff.

A real overheating problem would normally see the temperature reading drop rapidly once you remove the load from the engine unless it has totally failed due to stuck thermostat, waterpump impeller came off inside the pump, no coolant, no airflow etc.

If it gets hot under load, but cools right off unloaded, then suspect things like partially plugged radiator (internal and external), scaling inside preventing heat transfer, low coolant etc.

 

[stsjuice]

gowiththegreen I just experienced the exact same thing as you did for overheating. After changing the thermostats and playing around with a cheap laser thermometer we called the JD guys out and it turned out to be the watter pump impeller had came off and ate the front and back part of the housing. $$$ If you check the head temp on the cab ladder side of the combine as soon as it shows hot if it's around the 215 or better it is running hot just not circulating coolant.

 

[chompy]

If the motor is truly hot, then you will have coolant coming out the overflow tank (unlesss you are running REALLY low on coolant). This happens with blocked cores, blocked screens, broken screen belts, broken fan belts, busted water pumps etc. If there is no coolant overflow, then the sensor may be suspect. Putting your hand on the radiator tank may not be an indicator of how hot the block is, particularly if the water pump isn't circulating.

On the 9x00 series you can see how hot the engine is, by seeing how full the overflow tank is. Not sure if the 50's have a clear tank, though.

 

[richard]

You might check that the serpintine belt is not slipping. If you can turn the fan by hand when the belt should be tight it may be your issue. If the belt is bad check the pulleys as well for the belt may be bottoming. Good luck, had the same trouble with a M11 2 seasons ago.