F2560 Engine Vibration

[Red Power]

I recently bought a F2560 with a heated Curtis Cab. I really like how it works but I have a concern. When I start it up and let it run at an idle (@1200 RPM), the hood and lock pin for the hood "rattle" so that it almost sounds like a mini jack hammer. The air cleaner housing has bounced so much that the hanger has worn into the plastic body. I speed the engine up to @1400-1500 RPM or faster, everything is really smooth. Is this common for the D1105 3 cyl. engine to run "out of balance" at low RPMs or is there somthing else? I can see the drive shaft from the engine to transmission seems to wobble on the transmission side but there appears to be no way of centering it. Also my experience with other drive shafts would suggest that if that caused the vibration at low RPMs it gets worse not better at high RPMs. Any help or explanation would be greatly appreciated. BTW I am new to this sight and I hope I don't get "shunned" for not having a "real" Kubota tractor. We have enough real RED farm tractors to cover that.

Thank you kindly for your time.

 

[kuboman]

I recently bought a F2560 with a heated Curtis Cab. I really like how it works but I have a concern. When I start it up and let it run at an idle (@1200 RPM), the hood and lock pin for the hood "rattle" so that it almost sounds like a mini jack hammer. The air cleaner housing has bounced so much that the hanger has worn into the plastic body. I speed the engine up to @1400-1500 RPM or faster, everything is really smooth. Is this common for the D1105 3 cyl. engine to run "out of balance" at low RPMs or is there somthing else? I can see the drive shaft from the engine to transmission seems to wobble on the transmission side but there appears to be no way of centering it. Also my experience with other drive shafts would suggest that if that caused the vibration at low RPMs it gets worse not better at high RPMs. Any help or explanation would be greatly appreciated. BTW I am new to this sight and I hope I don't get "shunned" for not having a "real" Kubota tractor. We have enough real RED farm tractors to cover that.

Thank you kindly for your time.

How many hours on the unit? I would wonder if the rubber engine mounts are worn bad. I assume it also is running on all cylinders, no miss at low rpm.

 

[Red Power]

Thanks for the reply.

The F2560 has 925 hrs. on it. The engine mounts seem solid. If they were wore or lose wouldn't it rattle all the time? It seems to be running on all cylinders when checking the exhaust.

 

[kuboman]

Thanks for the reply.

The F2560 has 925 hrs. on it. The engine mounts seem solid. If they were wore or lose wouldn't it rattle all the time? It seems to be running on all cylinders when checking the exhaust.

When you say it is vibrating can you see the engine vibrating or is it just a felt vibration?
If you can see the engine jumping around I would still suspect the engine mounts.
Have you checked the u-joints on the drive shaft to the tranny?

 

[Red Power]

The engine doesn't vibrate independently from the frame, the mounts appear solid. The sides of the hood when down "flap" and the lock pin on the left side jumps up and down even with the spring tension. The whole back of the tractor vibrates as one. So I guess it could be a felt vibration. The u-joints have about .030" total slop in them. The spline has a little slop as well.

 

[kuboman]

The engine doesn't vibrate independently from the frame, the mounts appear solid. The sides of the hood when down "flap" and the lock pin on the left side jumps up and down even with the spring tension. The whole back of the tractor vibrates as one. So I guess it could be a felt vibration. The u-joints have about .030" total slop in them. The spline has a little slop as well.

I would consider replacing the u-joints as they have too much slack but I doubt they are your vibration. They will give more of a high frequency 'buzz' than a shake. From what you describe your vibration is just a normal shake from a 3 cylinder engine. Try changing your idle up or down so you get out of the shake range. In my experience most engines have a rpm where they will vibrate worse than in the rest of the rpm range.
Give it a try and let us all know.