Overheating M9540

[Rambo33]

Hi,

A friend recently bought a M9540 with a front 3 point linkage to run a mulcher. He's new to tractors and he was complaining about it overheating, then he proceeded to tell me it is running at 2600rpm. I have very little experience with kubotas, is this normal? It seems very high and can't be good in the long run.

 

[Tx Jim]

According to Tractordata.com Kubota M9540 engine is rated at 2600 rpm. Are radiator fins free of debris? It's possible thermostat is stuck. What condition is fan belt & is it snug. When engine is cool remove radiator cap, start engine & look inside radiator neck for tiny bubbles. Bubbles indicate engine compression is getting into cooling system.

 

[5030]

Sounds to me like it could be a number of issues but most likely a plugged with crud radiator. Tell him to get a Radiator Genie and clean it out and clean it often, along with all the other heat exchangers out front like the charge air cooler, the AC condenser (of it has one) and the transmission oil cooler. as well. I clean mine daily when farming, every evening.

In fact I carry a small HF Bauer 20 volt blower behind the seat to blow out the rad and components in the field if chaff gets to be an issue. Only takes a few seconds to clear them.

Any implement like a mulcher out front will produce a lot of chaff and fines that get sucked right into the radiator immediately. Overheating the engine consistently will eventually cause severe mechanical issues.

 

[Jchonline]

As always start with the simple stuff, eliminate it as a possible issue then progress. Tx Jim has great suggestions. You can also check coolant temps on the supply and return side to see if the rad is doing its job.

 

[JWR]

Overheating seems to be a frequent complaint with Kubotas. My experience is all with the smaller ones however. These principles apply regardless of size:
1) Unlikely to have anything to do with rpm
2) Both posts 2 and 3 offer good comments on it ...first make sure the radiator screen and fins are clear and clean. That is byfar the most common cause of overheating. My 81hp MF has never ever overheated except when seeds and weeds obscured the radiator and prevented air flow.
3) While diesels are a little less sensitive to coolant pressure (maybe?) you need to make sure the radiator cap is holding pressure. Coolant boils at a much lower pressure for a given temperature. If you replace the thermostat or prove that the thermostat is letting coolant to the radiator then check the cap because water boils at a higher temp proportional to pressure. That's what the radiator cap is for.
Note: My local tractor repair shop has simple quick and easy tools for pressurizing the radiator, finding leaks if any and detecting bubbles coming from combustion.
4) If you have bubbles coming from combustion you probably have a blown head gasket or even worse a cracked head if you ran it super hot for a long time.
5) When the engine heats up you should get some overflow of coolant to the plastic jug. That should be sucked back into the radiator when the engine cools. After it cools check the radiator level. If it is full you probably do not have these other diseases.
6) I have always questioned the adequacy of the water pumps on Kubotas. They OUGHT TO BE overkill and provide way more flow than required. I'm not so sure they do. I cannot say this applies to the large Kubotas (??)

Please let us know what you find.

 

[5030]

As always start with the simple stuff,

...and the simplest thing is removing any blockage from the radiator, which I believe is the issue anyway.

 

[Rambo33]

Thanks everyone. I'll pass on the advice. I know he's very diligent with his skid steers so I'd be surprised if he's been lazy with this. I've used fords, fiats, deeres, deutzs, but never a kubota hence why the 2600rpm working rpm was surprising.

 

[Hay Dude]

Thoroughly clean the radiator with garden hose sprayer set on the stream spray mode, then re-assess.
Won’t cost anything but 1/2 hour of time and that’s always been the culprit for overheating on mine.

 

[Rambo33]

Out of curiosity, Do all kubotas run high rpms like that? I have a 100hp tractor that is making 100hp at 2200 rpm and 375nm of torque at 1600 rpm. The 9540 i read is making about 320nm at 1500rpm. I went onto another manufactures site and read up on one of their 90hp tractors, 90hp at 2300rpm and 351nm of torque at 1500rpm.

 

[Rambo33]

Some pics of it in action.