Hello guys ,
I have a hydraulic problem with a 951c loader. serial 69h3944.
Hydraulic fluid looks like white foam. The hydraulic pump makes a loud noise. When used under pressure with a loaded bucket, it struggles to almost lift and the pump makes a loud noise. The noise occurs under both lift and bucket load.
What to check?
Thank you

Hi, uisum.
I'm gonna stick my neck out here and suggest that your pump may be beyond its use-by date and it is by-passing inside the pump.

Just my 0.02.

Hello
can I remove the 4 bolts that are behind the pump to give them a look?
Thanks you

Foaming oil usually means the system is picking up air. Check for suction line leaks or leaking seals.

Hello old ...
where is the suction line located?

Hi, uisum.
It will be a fairly big line running from low down on the tank to the pump. Taking the floor plates out may help in locating it.

If the fault does lie with suction line, there MAY be some signs of oil leakage at the site as the system is normally pressurized when working.

Just my 0.02.

Hello
no kind of loss there.
l oil is like milk. I'm not sure it's foaming.
I took it out and put it in the bins. Could that be the problem of loud noise during exertion?
The hydraulics work, but if you strain for example: bucket on the ground to lift the loader you will hear a loud screech in the pump.
when I load the bucket full of earth and lift I hear a loud noise ..

Water in the oil will cause it to go white as well as air leaks. The suction line has three rubber hose couplings and clamp connections which are usual suspects for leakage. Leaking o-rings at flange connections could also be a problem.
Pump cavitation due to air leakage could be the source of noise from the pump.

Old wrote:

Water in the oil will cause it to go white as well as air leaks. The suction line has three rubber hose couplings and clamp connections which are usual suspects for leakage. Leaking o-rings at flange connections could also be a problem.
Pump cavitation due to air leakage could be the source of noise from the pump.


 

I didn't quite understand where these suction lines are located.
You say under the hydraulic oil tank? I don't see any leaks here 'it's all dry.
Is it possible that the milky oil creates loud noises in the pump and loss of power?
When I unscrewed the 4 bolts of the pump I felt some air...

Hi, uisum.
The suction line to the hydraulic pump will be a bigger, low pressure line, not heavy construction like the high pressure hoses. It has been a LONG time since I had anything to do with these old girls but I think it starts either under the hydraulic tank or on the inboard side near the bottom and will lead to the hydraulic pump, hence the suggestion to remove the floor plates.

'Kwestyun': How long has it been making these noises and been low on hydraulic power?

'Nuther 'kwestyun': Has it been getting steadily worse or did it suddenly start doing these things?

Just my 0.02.