rock-shaft leak

[wango tango]

i presume i have a leak of some type since my rock-shaft is hiccuping and wont stay up for very long when the tractor is off.

i have a JD manual but would like some sort of feel for what the issue could be before i start tearing into stuff. i'm fairly well inclined mechanically but want to have a better plan than just dis-assembly/reassembly instructions.

this is on a 4410 with an HST.

anyone have any ideas or comments?

 

[Bigfoot62]

Just guessing here, but I would think that it would probably be the packing on the lift cylinder. Less likely, but could possibly the control valve or the bypass valve.

 

[beenthere]

Here is the rockshaft leakage test from the tech manual. But you mention that is what you already have.

Also, how is the filter?
Per the tech manual:
NOTE: If changes in the operation of the 3-point hitch
lift capacity are detected or the rockshaft control valve
should begin to react slowly, erratic or fail to cycle
properly; performance of this service procedure may
be required.

 

[jenkinsph]

i presume i have a leak of some type since my rock-shaft is hiccuping and wont stay up for very long when the tractor is off.

i have a JD manual but would like some sort of feel for what the issue could be before i start tearing into stuff. i'm fairly well inclined mechanically but want to have a better plan than just dis-assembly/reassembly instructions.

this is on a 4410 with an HST.

anyone have any ideas or comments?

With the hitch fully raised and engine running close the Rate of Drop control under the seat fully. Then shut the engine down and see if it still leaks down. If it still lowers rapidly I would suspect the rockshaft cylinder, if it doesn't drop then I would suspect the valves.