Kohler Command 25 output shaft getting very hot

Hi,

I have a portable sawmill with a Kohler Command 25 V twin horizontal shaft. I was having trouble with the drive belts and noticed that it seems to be due to the motor shaft getting very hot, heating up the pulley and then the belts. This would only take a few minutes!

I have even removed the pulley and belts and still, the shaft gets very hot very quickly.

There is no end play on the shaft. If I tap the shaft a little, then there is a little end play, but when the engine is started again - shaft gets hot and then when stopped again, once again no end play. The engine still sounds fine and there are no strange noises. I removed the oil filter, turned the engine over a couple of times and oil spouts out but not sure how to check how much pressure when the engine running.

Does anybody have any ideas? I don't have much experience with engine repair but do OK if I know what the problem is.

Any suggestions or advice greatly appreciated.

Thanks,

Mike

I can't say for sure, but your bearing is out or on the verge of going out..... It's not not getting the oil to it for some reason.........

IL Engine and a couple others are more adept on those twin Kohler's than I am...... They will chime in later .....

Please post the model number of the engine and the spec also..... That will be very helpful........

Plus Tard Mon Ami ~!~!

Thanks for the quick reply.

It is a Kohler CH25, 725cc (44 cu inch), 83mm (3.27in) bore, 67mm (2.64in) stroke.

The manual doesn't show a bearing as such so presumably the end plate acts as a bush? Yeah, my main suspicion at the moment is inline with yours - oil pressure or blocked oil line that goes to the bearing...either way it looks like I might have to crack it open!

I suspect that you are getting some oil flow through that end cap bearing, because that bearing also has the passageway that feeds oil to the rod cap surfaces. So if the sump bearing isn't getting any oil neither is the rods and they won't last long. How much side load is put on the crankshaft when the belts are tight and the saw is running. Could be a failure do to overloading the sump bearing. Also there should be a small metal tube that fits between the engine block and the sump cover that there was issues with it splitting open and dumping the oil back into the engine instead of feeding the bearings. That tube is located along the mating surface between the engine block and side cover so it can be inspected while the engine is apart.

A small amount of in and out play on the crankshaft is normal, but side to side would be a problem. There are two ways to check oil pressure. One is to remove the oil pressure sending unit and screw a oil pressure gauge hose into that hole and check running pressure. the other is a cap that replaces the oil filter and the oil pressure gauge connects to it.

I would say that you will need to open it up and take a look. the oil pickup tube on the oil pump was an issue on some of the Command engines so that could be the issue.

https://kohlerpower.com/en/engines/manuals

scroll down page for your engine, have all numbers, letters, etc.