3-Point Hitch LEAKING LIFT ARM ?

[KoonHunter51]

FarmPro (Jinma) 2430 4x4

Have a light leak from where the lift arm attaches
Diagram shows o-ring on both sides of shaft that controls lift
Just wondering if a complete dis-assembly is required to get to the o-ring (If that is cause) ?
I see that o-ring & gasket "Kits" are available for rebuild but lift works great otherwise
Thanks, David

 

[Ricks284]

Did you get a Jinma toolbox with your tractor? There were several o-rings and gaskets included in my toolbox and some of them were for the 3-point mechanism. I just bought the rebuild kit, but I used it for the valves and piston, not the lift arms. So I'm not sure exactly how you'd replace the seals on the lift arms. But I think the lift arms use big rubber gaskets with metal springs inside them - I'm not sure if they also use o-rings, but you might need to replace both.

I had to drain the hyd fluid to get to the piston and it wasn't too hard if you need to go that route (removing the 3-pt top link to get to the inside of the lift arms mechanism).

 

[KoonHunter51]

On this 300 series tractor diagram shows a couple bushings & o-ring on each lift shaft
Just wondering if o-ring is inside or outside of box
Probably remove seat & top for more closer observation
Lift works great, so I was not gonna do a complete dis-assembly
David

 

[Ricks284]

On this 300 series tractor diagram shows a couple bushings & o-ring on each lift shaft
Just wondering if o-ring is inside or outside of box
Probably remove seat & top for more closer observation
Lift works great, so I was not gonna do a complete dis-assembly
David

I'm not sure removing the seat will help much, unfortunately... unless you decide to remove the hyd filter.
Sliding the seat all the way forward will give you pretty good access to the lift arms from the back of the tractor.

I think you're probably going to have to drain the fluid and remove the back cover of the hyd fluid tank in order to replace that o-ring. Even if you could pull the lift arms without removing that cover, the hyd fluid would drain out the lift arm hole. So you'd prolly be better off draining the hyd fluid first anyway. Although I didn't remove the lift arms on my Jinma 284, I spent a lot of time back there looking at the mechanism inside the hyd fluid tank. Pulling that back cover off is pretty easy once you've drained the fluid -- it's just removing six bolts.

 

[KoonHunter51]

As pictured, this Jinma has a top cover on the tank
The diagram in manual does not show the top cover
I have drained & replaced filter & new fluid when I first bought tractor, draining is no problem
Just not wanting to get in to a major rebuild over a small leak (I have about 8/9 gal fluid)
David

 

[zonta223]

Contact Tommy from Affordable Tractors. He is a great guy and is active in these forums. He will be able to point you in the right direction

 

[KoonHunter51]

Yes, zonta223, Tommy has helped me in the past & I have bought parts from Affordable
I guess I'm gonna do more diagnose to see if the O-rings is all I need, or if I need a more complete kit
Thanks, David

 

[Ricks284]

As pictured, this Jinma has a top cover on the tank
The diagram in manual does not show the top cover

Gotcha - yours is definitely different than mine. The manual is pretty accurate for my 2004 model. It looks like they made some improvements on later models - removing the tank cover without draining the fluid would really save time (and fluid) compared to the way I have to do it. Good luck with it - hope it's an easy fix for you.

 

[zonta223]

Yes, zonta223, Tommy has helped me in the past & I have bought parts from Affordable
I guess I'm gonna do more diagnose to see if the O-rings is all I need, or if I need a more complete kit
Thanks, David

Not only does he sell the parts.....He would be willing to tell you how to do the O rings and if its an easy job

 

[Woody65]

It was a pretty simple fix on my JD 4300. I took off the lift arms and removed the bushings and O-rings. Put the new ones in and tighten back up. Took about 15 minutes. In my case, there was a slight leak and after a quick investigation, the bolt holding the lift arm on backed off a bit and the O- ring jumped the bushing. The schematic on yours doesn't look that different than mine.

This is how I found it



Fixed

 

[KoonHunter51]

Good pics woody,
I ordered the 2 O-rings from the parts schematic I have, hope they are right ones
David

 

[KoonHunter51]

Well, of course the O-rings were too small will try to match at local hydraulics shop tomorrow
I did dis-mantle & got a look inside & I am a little confused.
I got the outside bushings & the O-rings out, but could nor figure out how to remove the inside bushings, removal not needed anyway to replace just the O-rings.
Pictures added
Looks like the insides have to be removed to get shaft out.
The O-rings looked pretty good, the leaky side had a lot of oil on it, the non leaky side was dryer, bushings look like no wear also.
Can't figure out why this set-up doesn't leak anyway, after removing O-rings & outside bushings, arms & shaft had some play on both sides, vertical & horizontal.
I think I should have lived with the leak, or waited until leak much worse
David

 

[KoonHunter51]

Lift goes too high now
OK, Thanks to Circle G I did get right O-Rings
I marked the lift arms when removed, but I must have re-installed wrong.
Lift now does not engage until nearly at top, Pressure is great "Too Much"
With weight (Bush Hog) lowers too ground
Lifted too high & broke both stabilizer chain eye bolts
Removed top again & can't figure out exact location of lift arms on shaft
Any one have details ?

Does lift need adjustment or just arms re-locate ?
Thanks David

 

[Woody65]

Mine has an adjustment cable attached to the housing just below the seat. See pic below. Don't know if it will help at all. Different brand tractors.

 

[Ricks284]

Lift goes too high now
OK, Thanks to Circle G I did get right O-Rings
I marked the lift arms when removed, but I must have re-installed wrong.
Lift now does not engage until nearly at top, Pressure is great "Too Much"
With weight (Bush Hog) lowers too ground
Lifted too high & broke both stabilizer chain eye bolts
Removed top again & can't figure out exact location of lift arms on shaft
Any one have details ?

Does lift need adjustment or just arms re-locate ?
Thanks David

While reinstalling the 3-point piston on mine, the hyd fluid was drained, so I was able to move the lift arms by hand and mark the high/low points. Then I used those marks to adjust the stops attached to the handle. Could you do something similar on yours? But maybe using power to adjust if you don't want to drain the fluid.

I didn't remove the lift arms on mine, so I can't help with what to look for inside them. But I could take photos of the outside if you think that might help with reinstalling your lift arms. I'd say that you don't need to adjust the stops attached to the handle like I did, because yours were probably right when you started. So if you can just find the right position for the lift arms when reinstalling them on the shaft, you should be good to go.