hydraulics

[svenandersen]

Here"s probably a simple question. I just got a JD2640 with a loader. Sometimes the loader struggles to go up, especially at lower RPMs and the bucket slowly tips forward when its loaded with weight. Is it a valve, the pump itself? Other ideas?

 

[Tx Jim]

Many things can affect the performance of closed-center hyd's on JD's.
First thing I would check as far as for lack of speed raising is stand-by-pressure which should be 2250-2350 psi,change hyd filter & clean sump screen. Also look in hyd oil filler hole with engine running,3pt raised for "spraying oil". On the bucket tilting by itself that could be a leaking spool on control valve or bucket cylinder packing.

 

[svenandersen]

Thanks for your advice. All good ideas to follow up with.
Best,
Sven

 

[buickanddeere]

Where are the loader hydraulics connected to the tractor? When was the last time the trans screen and filter were serviced?

 

[cannonball]

can you give more information on tractor...reverser, high-low what clutch does it have...do you have foot on clutch when the chattering is happening...the tilting bucket can be cylinder bypassing or loader valve bad

 

[svenandersen]

Its a 1980. There is a hi-lo lever left of the steering wheel. On the floor, theres two shifters, one for hi lo- reverse. The other is 4-speed range. The loader hydraulics plug in underneath on the right side, approx below where your right foot would rest. The loader labors and is jerky and seems worse with some weight on it. Sometimes it sems to be better if I increase the RPM. It doesn't make any difference if I have the clutch in or not.

 

[svenandersen]

The loader connections are underneath on the right side, about where my right foot would rest. I got it from a dealer so I don't know the history.
Thanks

 

[buickanddeere]

Assuming then the loader has it"'s own joystick control and has no connection to the scv connectors. That is two positive facts.
The oil must return into a ported filter cover, not just dumping straight into the transmission case.
Ensure there is no flow through the return line from the joystick when the loader is not being raised or lowered.
Should do a pressure test on the transmission pump circuit to ensure no internal leaks. Contaminated oil and plugged filters will hammer the oil lines and/or make valves stick.
Any noise from the front pump coupler/drive shafts.?

 

[svenandersen]

Thanks,
I'll check and get back to you.
Its been really hot here to work on the tractor
;(