Problem with hydraulics John Deere 3350

[Claus]

Hello, dear forum participants. I have the following problem on tractor JD3350.
The hydraulics work very poorly, for example, it barely lifts the booms of a trailed sprayer to unfold them. Or it lifts an empty trailer, but slowly. The steering works fine for a while, but then it becomes stiff (it becomes very difficult to turn the steering wheel).

A year ago, the oil pump (the one in the transmission housing) was replaced. Also, a repaired hydraulic pump was installed in the spring. The hydraulic distributor was recently serviced.
But none of this solved the problem. When the hydraulic oil is cold, the hydraulics still work more or less. But when the oil heats up, the problems become obvious.

Perhaps some of you have encountered a hydraulic system like my tractor has, and can tell me what the cause might be?

 

[flywheel]

Hydraulic system has internal leak most likely..get john deere mechanic to pressure test Hydraulic system .

 

[Claus]

Hydraulic system has internal leak most likely..get john deere mechanic to pressure test Hydraulic system .

Thanks for the reply. Do you mean a leak after the hydraulic pump?
Probably it should be a problem in some valve (maybe the main one, the one after the hydraulic distributor)?

 

[celtis man]

Thanks for the reply. Do you mean a leak after the hydraulic pump?
Probably it should be a problem in some valve (maybe the main one, the one after the hydraulic distributor)?

It could be an internal leak, aren't there internal steel pipes that I have heard split.
@Tractortech is the best man to ask

 

[Tractortech]

Now Then...
Some in depth testing will be required with some pressure guages..

 

[marco]

Could be seals in his low clutch pack

 

[L P]

Could be seals in his low clutch pack

Doesn't that just affect hydraulics in hi range on the hi-lo? Steering orbital caused similar issues on my old 4240 when the oil got warm, it worked perfectly when cold though for half an hour or so. Another place to look is internal lift ram seals.

 

[Claus]

Now Then...
Some in depth testing will be required with some pressure guages..

I don't know, maybe it is also related to the main problem in hydraulics. Very soon the splines on the hydraulic pump coupling wear out... very high load on the rotation of the hydraulic pump? We buy original couplings from a local dealer.