JD 624J low lift power

[farmerlund]

I picked up a used 624J,ser#596401. 13,000hrs. The boom lift power is pretty weak. Can someone send me the diagnostics and pump pressures for this machine. And the testing procedures.
Is the relief valve for lift function adjustable?

Thanks Steve

 

[farmerlund]

Found this in the display. If it doesn’t read a pressure it will be low or in default? It has more lifting Power if I hold the curl function at the same time.

 

[SlatcoAu]

Broken wire or wire going to ground. Most cost effective thing to check first although admittedly the harnesses are in often difficult places. Sorry, I don't have any pin outs for that machine.

 

[Diesel Dave]

I suspect someone has enabled the “spin control“ option in the machine monitor.
“Spin control“ system looked at hydraulic system pressure data from a transducer in the hydraulic manifold.
Only the 644J had the available option but I’m sure it is still there in the 624J monitor to select.
You need to be in service mode to enable or disable options.
IIRC to get into service mode you hold the select button down for 5 seconds.

 

[farmerlund]

I suspect someone has enabled the “spin control“ option in the machine monitor.
“Spin control“ system looked at hydraulic system pressure data from a transducer in the hydraulic manifold.
Only the 644J had the available option but I’m sure it is still there in the 624J monitor to select.
You need to be in service mode to enable or disable options.
IIRC to get into service mode you hold the select button down for 5 seconds.

OK. will that make it act strange or just give the code? Mine has a spin control button on the key pad by the key. not sure if this machine has that option on it

 

[Diesel Dave]

Would just create the code.
I misspoke earlier , the option was available on the 624J serial number 611797 and up .
Regardless , someone may have enabled the spin control option in your monitor

 

[mg2361]

If rim pull is enabled, does your engine rpm drop more than usual when activating the loader function over relief? Spin control only reduces the engine rpm to control rim pull. Obviously, lower engine rpm means slower hydraulics.

Check your messages.

 

[farmerlund]

Would just create the code.
I misspoke earlier , the option was available on the 624J serial number 611797 and up .
Regardless , someone may have enabled the spin control option in your monitor

I will check it out. thanks. the boom lift stalls out with the loader in neutral. more throttle, engine rpm doesn't make it lift.

 

[farmerlund]

If rim pull is enabled, does your engine rpm drop more than usual when activating the loader function over relief? Spin control only reduces the engine rpm to control rim pull. Obviously, lower engine rpm means slower hydraulics.

Check your messages.

Thanks for the DM. one other thing I discovered this am is. if I hold the curl bucket function at the same time as lift, it will lift better than just the boom lift by it self.

 

[farmerlund]

So I finally got the problem fixed this summer. Turns out the pump was loosing the signal from the main hyd stack to keep the pump stroked. JD knows it had a problem with these machines and there is an updated control valve to replace the older version. something to do with super small ports and check balls in the control block.
Anyways, new main stack and it workes as it should. Poblem solved.