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Discussion Starter #1
Has renovated the hydraulic lift, and now the arms go slowly. But if I pull the outer hydraulic lever, backwards, then the arms begin to move at the right speed again.
And if I bring the lever back before the arms are in the top, the arms will stop for a short while and continue at the right speed when the lever is in the middle position again.
When I then lower the hydraulic arms and raise them again, they go slowly again ..... and then you have to redo the procedure.
Before the renovation, this was not the problem. Does anyone know what has happened or what is wrong? Hope you understand my bad language!
 

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Has renovated the hydraulic lift, and now the arms go slowly. But if I pull the outer hydraulic lever, backwards, then the arms begin to move at the right speed again.
And if I bring the lever back before the arms are in the top, the arms will stop for a short while and continue at the right speed when the lever is in the middle position again.
When I then lower the hydraulic arms and raise them again, they go slowly again ..... and then you have to redo the procedure.
Before the renovation, this was not the problem. Does anyone know what has happened or what is wrong? Hope you understand my bad language!
By renovated, do you mean rebuilt?
What was actually rebuilt, or replaced?

Whenever the lift is rebuilt and items replaced, the lift(rockshaft) valve assembly had to be adjusted. The step-by-step adjustment procedure is listed in the Technical Manual. You'll need the tech-manual(TM-4286) for instructions.
 
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Discussion Starter #3
By renovated, do you mean rebuilt?
What was actually rebuilt, or replaced?

Whenever the lift is rebuilt and items replaced, the lift(rockshaft) valve assembly had to be adjusted. The step-by-step adjustment procedure is listed in the Technical Manual. You'll need the tech-manual(TM-4286) for instructions.
Thanks for the reply!
It was my father who did the job, and he had done it as a JD mechanic a couple of times before, with no problems. He changed bushes, o-rings and some steel ball / valve etc. And only JD parts were used.
Very interesting, I have never heard anything about adjusting ..... I'll check it out!
But why does the lift go faster when I touch the external hydraulic lever? (without anything connected to the tractor)
 

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With engine running look inside hyd filler hole for moving oil. Having to move scv lever in order to increase 3 pt raise speed sounds as if 1 or more poppet valves in scv isn't seating properly. Remove hose(key 4) in photo between scv & rockshaft(3 pt) housing & with scv levers in neutral start engine no oil should exit both open fittings. Ditto on performing the L.D control linkage adjustments outlined in JD tech manual.
 

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Discussion Starter #6
With engine running look inside hyd filler hole for moving oil. Having to move scv lever in order to increase 3 pt raise speed sounds as if 1 or more poppet valves in scv isn't seating properly. Remove hose(key 4) in photo between scv & rockshaft(3 pt) housing & with scv levers in neutral start engine no oil should exit both open fittings. Ditto on performing the L.D control linkage adjustments outlined in JD tech manual.
Thanks! I have to check it out!
Okay, I've been thinking about it too, that there might be something wrong there ..... but the scv unit is untouched, and everything worked as it would before the operation (except that the large o-ring around the lift piston leaked)
I think it would be weird if there was a problem with a valve, right after repairing another fault?
Tried to pull the scv lever first, but it doesn't help. I have to pull the lifting lever first.
I filmed a little in the autumn when I was going to test the pressure in the system. There seems to be no leakage to the pressure side at least. You are welcome to watch the clip if you have time.

https://youtu.be/cApu-Ne_Eps
 

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Discussion Starter #7
With engine running look inside hyd filler hole for moving oil. Having to move scv lever in order to increase 3 pt raise speed sounds as if 1 or more poppet valves in scv isn't seating properly. Remove hose(key 4) in photo between scv & rockshaft(3 pt) housing & with scv levers in neutral start engine no oil should exit both open fittings. Ditto on performing the L.D control linkage adjustments outlined in JD tech manual.
Stupid questions maybe, but when will it normally come oil, and from which point?
How much pressure is in the hose?
 

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Stupid questions maybe, but when will it normally come oil, and from which point?
How much pressure is in the hose?
I've never check hyd pressure in this hose but if there was pressure it couldn't be but a few 100 psi due to the fact the hose is held in place with "clamps". The important thing is there should be no pressure with scv levers in neutral position when engine is running.
 

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Discussion Starter #9
I've never check hyd pressure in this hose but if there was pressure it couldn't be but a few 100 psi due to the fact the hose is held in place with "clamps". The important thing is there should be no pressure with scv levers in neutral position when engine is running.
Now I understand, the hose is only for oil return from the scv? I thought it was constant pressure .... but then I know! If there is leakage in the scv, I understand that the lift can go slow, but should I not even feel that the power steering goes slower? (has no priority valve)
 

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I understand that the lift can go slow, but should I not even feel that the power steering goes slower? (has no priority valve)
Your tractor should have a flow control AKA pressure control valve bolted to lower RH side by hyd filter that gives power steering priority to hyd pressure.
 

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I've never check hyd pressure in this hose but if there was pressure it couldn't be but a few 100 psi due to the fact the hose is held in place with "clamps". The important thing is there should be no pressure with scv levers in neutral position when engine is running.
Now I understand, the hose is only for oil return from the scv? I thought it was constant pressure .... but then I know! If there is leakage in the scv, I understand that the lift can go slow, but should I not even feel that the power steering goes slower? (has no priority valve)
That is the return to sump for the SVCs.

If you think the SCV(s) are leaking, you could cap the feed line to them, from the flow control valve.
 
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Discussion Starter #13
That is the return to sump for the SVCs.

If you think the SCV(s) are leaking, you could cap the feed line to them, from the flow control valve.
Thanks for the reply, but as I said, I have no priority / pressure control valve. Should start by removing the small hose, and see if there is any oil
 

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The power steering is retrofitted, without the valve.
Thanks for the reply, but as I said, I have no priority / pressure control valve. Should start by removing the small hose, and see if there is any oil
Oops I ASSUMED it had a priority/flow control valve. I am guessing 1120 was not for USA market.
 
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Model 1120 was built for European sales not N American sales & probably came from factory with manual steering. If tractor doesn't have priority valve it should have a tee fitting(key 8) that supplies oil to scv that could be capped if scv is leaking internally.
 

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Discussion Starter #16
Oops I ASSUMED it had a priority/flow control valve. I am guessing 1120 was not for USA market.
It was for Europe, but I have heard that 1120 was also sold in Canada? The difference seems to be the cylinder volume, and a couple of horsepower more than 1020.
 

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Discussion Starter #17
Model 1120 was built for European sales not N American sales & probably came from factory with manual steering. If tractor doesn't have priority valve it should have a tee fitting(key 8) that supplies oil to scv that could be capped if scv is leaking internally.
Interesting picture, has never seen it before.
Min is of the model -69 and according to my father it was not intended to mount power steering on it. But I want to remember that there are -69 With power steering too, but I'm not sure. From -72 I know it was fitted.
I will test your suggestions, but my father thinks that there is a valve for the hydraulic lift that fails, but when it gets a "shock" from the scv, the valve opens as it should. But we'll see!
 

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Discussion Starter #18 (Edited)
Have checked the valves in detail on the JD parts now ..... when changing the valve seats it refers to ordering another type of valve. But the valves for the lift are not changed ...... can it be the wrong thing?:think:
Edit: Checked again, and I looked wrong .... it seems to be the same valve .... only the seat that is replaced.
 

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1120's American cousin 1020 could be ordered with manual or power steering. The manual steering model would not have priority valve. I sold 1020's when they were new.
 

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Discussion Starter #20
Today I have checked through the filler cap for the lift, and I will start by asking why the oil is foaming in the gearbox in the encircled area? As you may see, the oil is almost as yellow as the interior color.
 

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