Hough 65C Hydraulic whine

[JTWAT]

My loader has a loud whine in the hydraulics when I lift the bucket. Bucket tilt does no make noise, only lifting.
Any ideas? Oil is full, new filters and pump rebuilt.

 

[Tones]

Is it a gearpump or a load sencepump?

 

[kshansen]

Hough liked to use Vickers vane pumps on many, but did have some gear pump on the newest ones we had but they were all much bigger machines than this one.

One thing I would check for is a suction leak.

 

[JTWAT]

Yes it has the Vickers double vane pump on it. The main inlet pipe runs directly off the bottom of the reservoir.
The power steering pump also is fed directly from the reservoir, and both pumps feed a demand valve.
I don't have any leaks in that area so don't think I can be sucking air. Reservoir is also holding a slight bit of pressure.

 

[John C.]

If you steer at the same time as lifting the boom does the sound change?

 

[JTWAT]

Yes it does. I also have a problem with the boom lift control sticking in the up position.

 

[John C.]

It sounds like something stuck somewhere around the boom lift spool in the valve. Why did you rebuild the pump?

 

[kshansen]

Yes it does. I also have a problem with the boom lift control sticking in the up position.

I'm going to assume you are just not referring to the normal detente position of the control valve?

does this sticking also occur with engine off if you pull the lever back?

 

[JTWAT]

It sounds like something stuck somewhere around the boom lift spool in the valve. Why did you rebuild the pump?

Lift is slow to go up at idle. I have to rev engine to get it to move.

 

[JTWAT]

I'm going to assume you are just not referring to the normal detente position of the control valve?

does this sticking also occur with engine off if you pull the lever back?

Ill check that in the morning. I am thinking there is a problem in Demand Valve and Control Valve,

 

[JTWAT]

Lever does not stick with engine off. Only when raising boom running. Ill pull top off of hyd tank and check for oil movement and filters.