I've got a 931b cat that developed an overheating problem. I started to try to fix this problem with the basics. I flushed the system, new regulator(thermostat) replaced radiator hoses, new fluid. The problem continued. Prior to overheating the forward and reverse on the tactor seemed sluggish and required a position on the throttle that was well past mid position to get it to move. Any ideas? Thanks
Check that your brakes are releasing fully. If you have dry clutches they usually seize up if the brakes are too tight but wet clutches will allow you to run hot and ruin the brake drums. If you have a hill make sure it will coast down it. Later Bob
Thank you for a quick response. The tractor will coast well down a hill. Brakes do not seem to be an issue.
sometimes the small bering on the slave clutch is worn and is not quite working as mutch as you think, or out of adjustment, i would ck that to make sure its correct.
are you getting good air flow through your radiator core?
I'm going to get a service manual so I can identify the slave clutch and other components of the tractor, that will allow me to check the tractor for possible problems that you good folks are bringing up. As soon as I find out where the slave clutch is I will check it for proper adjustment. Thanks
I flushed the radiator and sprayed the fins, cleared a lot of dust, the core has good flow. The overheating problem developed suddenly, not gradually. Does the fact that it is requiring higher rpm to move the tractor forward or backwards play into this?
Is the torque temp gauge working and is it showing high or low temp? Sounds like parasitic load. Later Bob
I have a 931B that is having the same problem and was thinking about changing the thermostat until I read this thread. I cleaned the radiator and have good air flow. I do not see the resolution to this problem on this thread. Is there any other thing that would make the machine run hot other than brakes being too tight or cooling system failure? Do water pumps go bad/
Old thread warning! Water pumps can go bad. Most of the time, you cleaned the radiator, but it's still clogged enough with dirt and chaff that the airflow is the issue. Sometimes people will add hard water consistently, and the water side of the radiator will plug with lime deposits, obviously more likely on an old machine where it's had decades for somebody to add hard water, not on a new machine where they're more likely to use premixed antifreeze, and FIX the leaks. Get a non contact thermometer. Get the machine as hot as you dare, up to the edge of red if you can with it full of coolant, and immediately check the thermostat outlet to the radiator, the water pump inlet from the radiator, and the head and block temps. That will give you a good starting point to see what's going on. Did yours start overheating suddenly? or gradually,or has it done it as long as you've owned it? And how long does it take to cool off if you let it run at high idle?
I have to apologize for waiting so long to follow up on this thread and facing the embarassment of the solution. When this problem started I had recently topped off the coolant level on the 931B and was sure that it was not a low coolant issue. I used the a non contact thermometer to check the block and top of the radiator (inlet) while it was overheating to determine if I had a thermostat that was not opening and found the same temp at the block and radiator indicating that the thermostat was open and passing coolant. As it turned out the problem was low coolant level in the system (embarassing). I want to thank all for the suggestion and especially for the use of a non contact thermometer to determine the status of thermostat.
Apparently 3204's can get an air lock in the cooling system. There is a bolt or something that can be loosened up near the top rad. hose. I forget exactly what the shop that rebuilt the engine told me years ago. I've had to put 3 water pumps in mine. 1st one was just a crappy aftermarket that the hub came loose. Last year I ordered a water pump and it seized up in short order. They sent me another one and it seems good. Cat wanted over $1200.00 for a new water pump and $660.00 for a rebuilt one.
The Chinese are the major manufacturer of aftermarket water pumps for the 931B now, you can get them off Aliexpress for less than a couple of hundred bucks. https://www.aliexpress.com/item/32968536936.html
I paid a little over $200cad. And then had to pay about $30 extra to Fedex for brokerage fee's to get the replacement. I hate FedEx! Through the mail is the best if they can do it but UPS is better than Fedex because you get a price and there's no extra's.
Thanks for the tip concerning the vent and availbility of the water pumps