JD 2550 pump question

[MMagis]

Pretty sure my hydraulic issues have been narrowed down to a failing main pump (JD 2550). My initial assumption was to just buy a new pump, but I see John Deere offers a rebuild kit. Are there any opinions whether this is a route worth considering? It would save me some money, but I don't know enough about hydraulic pumps to know whether it would be worth the savings, or if I should just replace the pump since we're taking it out anyways. Thanks

 

[J_J]

At least do a flow and pressure test on the pump at the dealer.

 

[MMagis]

It has been pressure tested (not sure about flow).

 

[kennyd]

Just to be clear, are you talking about a 60s or 70s era utility tractor, or the modern era compact utility tractor sold just a few years ago?

 

[MMagis]

In between I guess. It's an '85 model.

TractorData.com John Deere 2550 tractor information

 

[Tx Jim]

MMagis
More diagnostics is required before frt pump replacement is deemed necessary as many frt(main) hyd pumps have been repaired/replaced to determine that this pump wasn't the problem!!!!!!!!. There are many things such as low & high pressure internal hyd leaks that can give the same symptoms as a failed frt hyd pump. Does your tractor have the options of hyd ind pto &/or hyd hi-lo or reverser. The supply tubes for each hyd function I asked about have a long/long history of failure causing hyd problems. Has hyd's been tested with hyd pto both on & off and with hyd hi-lo in both speeds????? Is tractor equipped with a FEL & if so what type valve controls FEL? Long story/short story no many technicians of this day & age know how to correctly diagnose a JD closed center hyd system of the early 60'-early 90's.

 

[J_J]

Hydraulics:
Type: closed center
Pressure: 2300 psi [158.6 bar]
Rear valves: 1 or 2
Pump flow: 13 gpm [49.2 lpm]


Did you see the 2300 relief pressure when you did the test.

Check your flow in a bucket using the 10 second rule. 13 GPM = 1.3 gal in 10 sec.

 

[DLTTrekkers]

Run all tests BEFORE stripping !

 

[MMagis]

It’s currently at the neighbors, and I wasn’t there when they checked it out so I can’t say for sure what all was tested. I’m guessing it wasn’t everything listed and more tests need to be done. I do know the pressure was sporadic, it may read good when the RPMs are increased but when decreased the pressure would go away and may or may not return. It does have Hi-Lo and independent PTO. It also has an FEL, independent valve, not off the remote (not sure if that answered the question?).

 

[Tx Jim]

Test FEL control valve to see if it's reverted to open center valve by aiming open hose in bucket or hyd filler hole with both control levers in neutral no oil should exit hose when engine is running. Also look in hyd filler hole for spraying oil when 3 pt is raised and engine is running which would indicate blown rockshaft control valve seals. Test hyd operation with both speeds of hi-lo & pto on/off and report back.