# help! hydraulic pressure just continues to build



## nmucowboy (Jan 27, 2015)

New to the forum. Hopefully there are some gentlemen here with the knowledge to help . I have an early 60's Ford 4000. Was moving my post hole digger to another garage, backed into the garage, had to lift up the digger a couple inches, all of a sudden the 3 pt just started shooting up! I dropped the lever to control the hydraulics all the way down, and she kept rising!. The spring on the top under the seat was fully compressed, the only thing I could do to relieve the pressure was to pop off the fill plug for the hydraulics. Oil started oozing out, not much, less than say a half cup of oil. Idk what the neck happened. After I relieved the pressure, I undid the 3 pt on my hole digger, the control arms on my tractor dropped all the way to the floor and oil shot out of the hydraulic fill hole hitting the ceiling I'm my garage! What is going on?!?! There was just a 150lb attachment sitting on the 3 pt then all of a sudden it just dropped to the floor?!?! Anyways one at a time. What would have made my hydraulics shoot up even when I had the control lever all the way down? Thanks
-Tim


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## Country Boy (Mar 18, 2010)

I'm not that familiar with Ford tractors, but its possible a relief valve stuck or that a control valve o-ring blew out allowing oil to go where it wasn't supposed to be. Was the oil at the correct level, or was it over filled? Its also possible that the lift cylinder seal went out on the plunger, allowing pressurized oil to get to the wrong side of the piston. Hopefully someone with more experience with these tractors sees this and can offer more help.


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## jhngardner367 (Apr 5, 2011)

I think Rich is spot-on about the relief valve or control valve.
Once the 3-pt was disconnected, the pressure had to go somewhere,and if the control valve was in the down position,it would go to the reservoir.
The fact that it shot out the fill hole indicates a faulty control valve,since the control valve limits the amount of fluid,and pressure in the control valve is limited by the relief valve (which is part of the control valve circuit).
I think you'll find the control valve has an internal problem.


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## harry16 (Dec 8, 2011)

Howdy nmucowboy,

Welcome to the New Holland / Ford Tractor Forum.

Is the spring behind the top link still compressed? If so, you need to take a crow bar and unstick it. The top link serves as the load sensing element for the draft control system. Used primarily for plowing. If the plows are pulling too hard, they push in on the top link causing the draft control system to pick up on the plows until the load is reduced to preset conditions. Something got into a bind to cause the top spring to be fully compressed. Did you back into anything with the PHD? Maybe the three point hookup to the PHD was in a bind, pushing in on the top link? 

Was your position control handle in the "up" position (item #32 on attached diagram). 

See attached diagram. Filler plug is #14 should have no pressure behind it. I suppose that fluid rushing/returning to the reservoir could splash out. Especially if you had a stuck unloader valve that suddenly released. Or a safety valve venting back to the reservoir due to excessive pressure? If you want to relieve pressure loosen pipe plug #19. That will give you a geyser! 

HTH. Post back.


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## jhngardner367 (Apr 5, 2011)

First, Welcome nmucowboy(sorry ,I just woke up!LOL!)!
Thanks Harry16,
I could only give him "generic" advice,since I don't have a manual.


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## nmucowboy (Jan 27, 2015)

Thanks for the replys gentlemen.

Also need to mention this. I forgot to mention this. When I took off the drive shaft from the pto, I noticed the shaft was seized. No sliding whatsoever. Must have been damaged somehow when it was taken off last or just by sitting around. Anyhow, think this may have played a factor in what I experienced?
Last night I also sealed back up the reservoir for the hydraulics and fired the tractor back up, the 3pt went up to and held at the half way point fine (was scared to put it through full ROM) 
And the spring under the seat for the top mount had decompressed as soon as I popped the cap off the hydro reservoir.
Also with no knowledge on this tractor, and not a whole lot of repair knowledge on tractors at all... How hard is it to replace a control valve if that is the issue? And what would that run me?


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## nmucowboy (Jan 27, 2015)

Harry16, I did take off the number 19 plug... Scared the crap outta me when it did it lol. When the hydraulics decided to have a mind of its own I was probably at about the 75% UP position


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## harry16 (Dec 8, 2011)

Your lift system should be back to normal after the spring was decompressed. Your PTO shaft is probably seized by rust. They're expensive. You might try soaking it in diesel.


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## nmucowboy (Jan 27, 2015)

Hey right on, got plenty of that laying around. Already sprayed it down with some wd40 but I will try diesel too


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## nmucowboy (Jan 27, 2015)

Should I be concerned about the teeth missing from my old starter? Really hoping this will not be needing me to pull the motor to pull out the Old teeth


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## nmucowboy (Jan 27, 2015)

Ok, and not to sound like an idiot... But where the heck do you refill the oil at? I feel like a moron, but just cannot seem to find an easy spot to dump in the oil...


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## BigT (Sep 15, 2014)

Howdy nmucowboy,

If you have a 4 cylinder 4000, see items #27 & #28 on attached diagram (engine assembly outside, 134,172.......). 

If you have a 3 cylinder 4000 see item #23A on attached diagram (cylinder head, block & related parts.....).

BTW, You are not the first guy to ask this question!!


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## nmucowboy (Jan 27, 2015)

haha, thanks BigT. I do have the 4 cylinder. I really appreciate the help.

On a side note, i am kind of upset with the guy who sold me this tractor. He was the "Oh yeah tractor runs great, no issues..." the kind of guy to make you feel like he took care of all his stuff. WELL, when i drained the oil to remove the oil filter to pull the starter, there was maybe a quart of oil in it, and holy hell was it thick. Pulled the oil filter, and seemed to just be full of sludge. Looks like i will have to be going through this tractor, front to back come spring before i use it to start working my field with it.


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## nmucowboy (Jan 27, 2015)

BigT said:


> If you have a 4 cylinder 4000, see items #27 & #28 on attached diagram (engine assembly outside, 134,172.......).
> 
> QUOTE]
> 
> that is where is thought the oil would go in at, there is a brether/filter there, i may have to look to see if the base for the filter unscrews from that filler neck. Thanks again


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## BigT (Sep 15, 2014)

There's a wing nut on top of the filler cap which I think adjusts the tightness so it doesn't fall off.


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## nmucowboy (Jan 27, 2015)

BigT said:


> There's a wing nut on top of the filler cap which I think adjusts the tightness so it doesn't fall off.


yeah, i took that cap off last night, and there was a filter under there too. I will have to take a pic to show you what i mean. It seems like it is doubling as a breather for the oil. There is a baffle in the way that makes pouring oil in quite difficult and messy.


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## nmucowboy (Jan 27, 2015)

figured it out. The piece The filter rests on pulls right out. Got her filled back up


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