Hydraulic Squeal Kubota 7610 HST

[Ideehoan]

Hoping someone can give me an idea what this noise is about. I'm getting an intermittent squeal kinda like older cars power steering when the wheel is cranked. It happens only when the speed control pedal is advanced. It's worst with rapid forward acceleration, but also in reverse but with a lower pitch and not as loud. It stops with easing off the pedal. Slow speed is OK. No change with loader, 3 point and PTO operation. The hydraulic fluid level is good, looks clean.

I'm snowblowing with a 3 pt blower. Wondering if the hydraulic pump or drive motor is going bad or what. I have not tried changing the filter yet. Tractor has about 500 hrs.

Thanks for any input.

[MIKE R]

I would try a fluid change. The noise from the way you described sounds like the pump is at its load limit. All hydro drives have a wine to them.

[Ideehoan]

I would try a fluid change. The noise from the way you described sounds like the pump is at its load limit. All hydro drives have a wine to them.

I was thinking a plugged filter might cause it. It's certainly not a normal HST sound. It's loud and nasty when it happens.
Thanks for the reply.

[Ideehoan]

I just had a service tech tell me the front d-shaft might cause this sound so I'll be looking at that.
Guess I should not assume it is hydraulic in origin.

[peterc38]

I just had a service tech tell me the front d-shaft might cause this sound so I'll be looking at that.
Guess I should not assume it is hydraulic in origin.

Read post #15 in this thread:

http://www.tractorbynet.com/forums/k...g-noise-2.html

[Ideehoan]

Aha! I suspect this is it. I'll post a report.
Thanks!

[Ideehoan]

Problem solved. Quite a relief, a few squirts of wd 40 took care of it.
There's a plastic shield around the front d shaft. It has a semi snug fit so it's in contact with the shaft. If it happens again I'll try sprayable grease like lithium or chain lube.

Thanks Peterc38!