How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask John Oliver Your Own Question
John Oliver
John Oliver,
Category: Agriculture and Farm Equipment
Satisfied Customers: 201
Experience:  manager at White Eagle Ag and Truck Services
Type Your Agriculture and Farm Equipment Question Here...
John Oliver is online now
A new question is answered every 9 seconds

I have a 1965 Deere 4020 Power Shift that I replaced the

Customer Question

I have a 1965 John Deere 4020 Power Shift that I replaced the load shaft seals and bushings. In the process I removed the Rock Shaft Housing Assembly to replace the parking pawl in the transmission. All is re-installed using new gaskets and all new fluid and filters. The problem is now the 3-Point will not move, not even try to move using the hydraulics. It worked fine before disassembly. I can move it by hand effortlessly. I made double sure that the cam follower arm was properly installed between the cam and the little follower wheel. Even took the fill neck off and verified that it was in the proper position. It is like there is no hydraulic pressure in the line that goes from the valve assembly to the 3-point cylinder. There is oil flowing but I can nearly stop it by putting my finger over the end of the line. All other hydraulics work great. I disassembled the valve body and cleaned - No change. Please advise!
Submitted: 9 months ago.
Category: Agriculture and Farm Equipment
Expert:  Dan replied 9 months ago.

Hi Nick My name is***** will try to help. sounds like there might be a problem with some linkage disconnected or there is a failed o ring allowing the pressure to bypass. You will have to remove the housing again to inspect and retrace your steps unfortunately. Let me know

Customer: replied 8 months ago.
I have removed both the Rock Shaft housing and the valve assembly twice and found no assembly error. I have obtained a diagram to verify that there are no missing parts and that they are in the right order. How can I check the pressure to the valve body? Is there any testing that can be done to verify the valve body is functioning properly?
Expert:  Dan replied 8 months ago.

Hi Nick, thanks for the update. I need to opt out for the pressure testing part on this model as i do not have a copy of the service book. there is an expert on here by the name of Kevin who can likely help with this or another expert. i am going to opt out and send a message over to him as well. i do not know his schedule but dont respnd back or the question will get locked back to me.

Expert:  John Oliver replied 8 months ago.

hey nick my name is ***** ***** you did the load control shaft did you have both draft and lift levers all the way in the down position? it is possable to install the shaft and miss the draft arm below and that will give you that same result. as far as testing the valve... if you have your 2200 psi at the SCV it will be at the rockshaft. test there and let me know. if no pressure its possable that the priority valve has jammed or other issues

Expert:  John Oliver replied 8 months ago.

any luck here?

Customer: replied 8 months ago.
Sorry, I have been unable to continue with the repairs until today. Had to get a gauge and some fittings. There is 2200psi at the 2 remotes in the rear of the tractor. All other hydraulic functions are working great. I have removed the oil fill tube and can see inside the rock shaft housing to verify the lever is between the rockshaft cam and the follower. It feels normal selecting ranges too. The cable is connected to the valve, I have taken the cable off and moved the linkage on the valve manually by hand and there is no change.
Expert:  John Oliver replied 8 months ago.

welcome nick. what about the load control shaft that you said you changed? when you changed it did you have both levers full forward?

Customer: replied 8 months ago.
in fact I had the rock shaft housing removed at the time and I could visibly see that it was installed properly between the forks.
Expert:  John Oliver replied 8 months ago.

so with your tests you have verified that it is not a pressure issue which is good. are the arms stuck up or down?

NO not the forks on top im talking about the load control shaft that contacts the draft arm at the bottom of the transmission case

Expert:  John Oliver replied 8 months ago.

it is posable to have the draft sense arm on the wrong side of the load control shaft

Customer: replied 8 months ago.
They are in the down position. They can easily be moved by hand upward but they will not stay by them selves.
Expert:  John Oliver replied 8 months ago.

if there stuck down i would put $$ on the load control shaft not being installed correctly

Customer: replied 8 months ago.
I could physically see that the load shaft was properly installed between the forks at the bottom of the draft arm underneath the differential. with the rock shaft housing removed i was both able to see and feel to verify this connection. I am 100% confident that part is correct. I've installed a few of them but I do know what you are talking about installing them wrong.
Expert:  John Oliver replied 8 months ago.


then really the only other thing it could be is a busted roll pin on the internal linkage assembly in the rockshaft valve

Expert:  John Oliver replied 8 months ago.

you have great pressure, the arms are free, you have verified that the linkages are in place correctly and no parts missing

whats left really?

are you online with JD parts? so that you can see the break down?

Customer: replied 8 months ago.
I have purchased a JD service manual for the 4000 sires tractors and i do have the diagrams. I find it very generic though and not very helpful.
Expert:  John Oliver replied 8 months ago.

i would download he tech manual..there about $20 online

parts breakdown is free.

Expert:  John Oliver replied 8 months ago.

go to the hydraulic section for your model and scroll down to "rockshaft control" there it show that roll pin i was talking about

Related Agriculture and Farm Equipment Questions