JD 2640 Loss of Hydarulics

[Rathpr]

Thanks for the replies. I have checked both filters and both are very clean. The fluid levels are also fine. I changed fluids about a year ago. I have checked other threads and it seems there are three primary reasons for hydraulic failure, clogged filters, a leak (some sort of gasket failure) or pump failure. I do not have clogged filters, there is no obvious leak, this seems like the pump would be the issue. Also I have no hydraulics for the front end loader, the three pt or power steering. I will make sure the drive coupler is intact although visually it looks OK and check the destroking screw. Thanks

 

[Rathpr]

Thanks for the replies. I have checked both filters and both are very clean. The fluid levels are also fine. I changed fluids about a year ago. I have checked other threads and it seems there are three primary reasons for hydraulic failure, clogged filters, a leak (some sort of gasket failure) or pump failure. I do not have clogged filters, there is no obvious leak, this seems like the pump would be the issue. Also I have no hydraulics for the front end loader, the three pt or power steering. I will make sure the drive coupler is intact although visually it looks OK and check the destroking screw. Also if I had a pump shut off screw where would this be located? Thanks

 

[Tx Jim]

Closed center hyd require diagnostics by a knowledgeable person. Many hyd pumps have been condemned to be faulty,replaced only to determine that replaced hyd pump was actually GOOD. What type valve controls FEL(scv or ind.)?

 

[Rathpr]

I dont know that much about hydraulics. The FEL control valve is a 2 Spool 5 GPM Eaton Cessna. I started the tractor and the coupler is working OK

 

[beenthere]

Rathpr
Was the hyd screen that you cleaned nylon or steel? key item #29

 

[Tx Jim]

I dont know that much about hydraulics. The FEL control valve is a 2 Spool 5 GPM Eaton Cessna. I started the tractor and the coupler is working OK

Disconnect FEL control valve return hose from tractor. Aim open end of hose in hyd filler hole behind seat. With engine running,valve control levers in neutral no oil should exit hose. Of course this test is invalid if frt pump isn't pumping any oil. Another test is with bucket under housing remove hyd filter housing & turn engine over for 15 seconds bucket should have 1-1/4 gal of oil in it.

 

[Tx Jim]

Rathpr
Was the hyd screen that you cleaned nylon or steel? key item #29

I'm curious what difference screen material matters?

 

[Spanner]

In Post #1 says he checked the filter. Thtat will be the external 'can' filter?

There is an internal screen in the bottom of the transmission case. Access by removing plug cap on RH Side.

A Clogged screen will cause loss of all your functions, especially if steering has gone since steering has priority in the circuit.

You don't say you checked this screen filter. Some models had a steel mesh screen, some had a nylon mesh.

When was the last Trans oil change?

Rathpr
Was the hyd screen that you cleaned nylon or steel? key item #29

I'm curious what difference screen material matters?

No difference I don't think Jim, other than to jog OP's memory and confirm he actually accessed the screen.

 

[beenthere]

tks Spanner.. was hoping to confirm that this screen was one of the two "filters" mentioned, in a subtle way.

 

[Spanner]

Yes BT. I was going in the same direction. Still not sure.
It sure 'seems' like suction screen problems...