3-Point Hitch Adjusting 3 PH for 485 Backhoe ?

[sunnyside360]

When installing/uninstalling the 485 backhoe to the 4320, I'm having trouble inserting/removing the 2 large pins that hold the backhoe in place. I use a floor jack to lift the backhoe just a little when installing and uninstalling the backhoe. Is there an adjustment for changing the up/down travel of the two top 3 PH arms which are also used for lifting/lowering the backhoe during install/uninstall?? If so, this may eliminate having to use the floor jack.

 

[Cidertom]

Two different adjustments may be required. The BH has a set of plates bolted on the "hooks" that the lift arms engage. These may need adjusting. The more likely is the 3pt pushrod is slightly out of adjustment. This rod is the control that provides the feedback for the position. If it loosens, the arms won't go to full height. Loosen the lock nut and slowly turn the ajdustment. it will bring up the arms to alow the pins to slip in. I have to do this adjustment about once a year on my 4520. I snug the lock nuts, but it still slips.

 

[AKfish]

Dang... there is that little adjustment rod, isn't there?!? I'm always learning and re-learning stuff here all the time.

Thanks, Tom.

AKfish

 

[sunnyside360]

Two different adjustments may be required. The BH has a set of plates bolted on the "hooks" that the lift arms engage. These may need adjusting. The more likely is the 3pt pushrod is slightly out of adjustment. This rod is the control that provides the feedback for the position. If it loosens, the arms won't go to full height. Loosen the lock nut and slowly turn the ajdustment. it will bring up the arms to alow the pins to slip in. I have to do this adjustment about once a year on my 4520. I snug the lock nuts, but it still slips.

Tom, many thanks for the info. It doesn't look like the set of plates on the hooks have moved so most likely have to adjust the rod. Can you tell me where the pushrod is that needs adjusted? I don't want to screw up something else. I guess I should invest in a shop manual soon.

 

[sunnyside360]

Dang... there is that little adjustment rod, isn't there?!? I'm always learning and re-learning stuff here all the time.

Thanks, Tom.

AKfish

Larry, I agree this is the best thing about this forum -- learning info and getting/giving help when needed. It's an invaluable resource for those who have tractors and equipment. Plus, it gives us retirees something to do in our spare time.

 

[Cidertom]

Looking at the back of the tractor: The left rockshaft arm. The pivot of that arm has the pushrod on it. It is kind of a pain to get to with the BH on, but that is how you need to adjust it. I loosen the lock nut, then attach the BH. Raise the rock shaft to full up. Slowly adjust the turnbuckle until the holes line up. While holding the turn buckle with a wrench tighten the lock nut. The pins should slip in easily.

One note, after you mount the BH, drop the rockshaft just a bit. I didn't and there was enough contact that the top rockhaft pin got worn to the point I had to dress it to get the lift rod back on.

 

[sunnyside360]

Cidertom, many thanks for your help. The rain here has finally stopped and I hope to get out today and make the adjustment.

 

[sunnyside360]

Looking at the back of the tractor: The left rockshaft arm. The pivot of that arm has the pushrod on it. It is kind of a pain to get to with the BH on, but that is how you need to adjust it. I loosen the lock nut, then attach the BH. Raise the rock shaft to full up. Slowly adjust the turnbuckle until the holes line up. While holding the turn buckle with a wrench tighten the lock nut. The pins should slip in easily.

One note, after you mount the BH, drop the rockshaft just a bit. I didn't and there was enough contact that the top rockhaft pin got worn to the point I had to dress it to get the lift rod back on.

Done. Turned the lock nut 1/4 turn so as to shorten the upstop rod and the rockshaft now lifts the BH high enough to insert the two L-pins. Thanks Tom.

 

[Cidertom]

Glad to help. Have fun

 

[USMC2531]

Hello,

First, please ignore my ignorance.

Second, lots of good info here, but could someone post a picture of the left rockshaft arm that has the pushrod and locknut on it that is used to adjust the 3 point hitch? Having trouble with attaching my 485 backhoe to my JD 4120 because the 3pnt hitch is out of adjustment.

thanks,
steve