Backhoe 3720 rockshaft malfunction backhoe removal

[Duble]

Yourkie: I don't know if you have resolved your BH removal problem as of this posting but since my last post on 10-3-2010 I have pursued this same problem with Deere & Company in an attempt to get this issue resolved. Since my post I bought a technical manual and have double checked the "Rockshaft Position Feedback Linkage Adjustment" as found on page 803 of the technical manual. This checked out OK. By turning the adjusting nut just a half turn to lengthen (increase the lift arms height) caused the relief valve to engage. I reset the linkage to the original adjustment. I also checked the "Lift Arms Adjustment" as found on page 799 and page 818 that indicate all angles are from the horizontal position. These also checked out OK. That leaves only one other possible thing that it could be, the movable latch plates being designed wrong or the drilled and tapped holes being placed in the wrong position.
I contacted JD customer service about the problem along with my suspicions and was more or less ignorded. With that put off I wrote a letter on September 16, 2010 to the CEO of Deere & Company (Samuel R. Allen) along with photos explaining and showing the problem I was having and also my disdain with their customer service department. Shortly thereafter I was contacted by a JD customer service representative "apologizing for any inconvience that I was experiencing and that they would be forwarding my letter to the factory". To make a long story short nothing happened for the next several months and after repeated calls to the Deere & Company's customer service representative that contacted me , nothing has been resolved.
In my letter to Samuel R. Allen I included a new design for their movable latch plates as well as the relative position for new drilled and tapped holes to correspond to the new movable latch plate design. If you look at he original drilled and tapped hole placement you will see that the tapped hole closest to the lift arm pin is so close to it that if the tapped hole's threads strip out you may not be able to use a through bolt with a nut on the end of it. The Lift arm could possible hit the nut. The new design for the movable latch plates that I designed takes care of that possibility. Being a machinist for 40 years I have some expertise in this area.
Since I have been unable to get Deere & Company to resolve this matter I have filed a complaint with the Attorney General's office in PA on March 24, 2011 and supplied them with all my correspondence, photos, timeline of correspondence with Deere & Company and other documentation. I have just received a letter back from them (May 25, 2011) stating that they have received my complaint, reviewed it and will attempt to resolve this issue with Deere & Company. If you also have not had your issue resolved you may want to also contact the Attorney General's office in PA since you are from the same state.
The issue is definetly the movable latch plates and I'm like you, when a manufacture shows on their CD and in the backhoe operator's manual that the BH can be removed from the operator's seat, then thats the way I want it to work. Yes, it can be done using the outriggers but that puts the operator in a position that can have bad consequences if one's not attentive to what one's doing.
While I'm not sure what the outcome will be at this point, the more owners whom complain about this problem, the more apt it is to be resolved. If anyone wishes to contact me in regard to this same problem you may reach me at (724) 545-9535) If the problem is not resolved by Deere & Company then I am going to have two new movable latch plates made to my new design and drill and tap new holes in the BH frame where needed. Hope this helps!

 

[jimgerken]

I just checked and found I never did follow up on a post here or in "Customization" showing my fix for this backhoe/rockshaft position deal. Basically, what I did was to form a one-eighth inch thick by one half inch wide by a couple inches long strip of flat metal into the open hook feature of the moveable metal plates on the 375 backhoe. I formed the metal in the open hook feature by bending and hammering it on the anvil, and eventually it fit really nice in the hooks (one on each plate). So it lines the open hook feature to make it's inside open bottom surface lower to the ground, by approx 1/8". I welded each of them in. Now with the plates remounted, the hoe gets lifted 1/8 inch higher with the same rockshaft setting. That was enough, now everything fits just fine, and the rockshaft adjustment can be made proper. Sorry I forgot to follow up. No pictures of this, although I could get one if this is unclear. I think if you need to do it, and look at the moveable brackets, my description will lead you to the solution. Its a 30 minute fix (less time than contacting the Attorney) with a tiny bit of scrap metal invested. I could have cut entire new plates out with the NC plasma machine, but figured I might just try this. Works so well I forgot all about the problem.
Good luck...

 

[Duble]

I also made a similar temporary fix to help solve this problem. I basically made the fix by using a 3/16 inch thick by 1 1/2 wide piece of angle iron custom cut and finished to fit into the hook area, then drilled and tapped it to the face of the movable latch plate. This helped me to confirm my original diagnosis of the problem. While this will let me temporarily remove the BH, the slotted holes are still resting tight against the 1/2 bolts and do not allow for any further adjustment should I need to make any future adjustment for any loss of motion or wear. Making new plates with the slots in a new position would be the best way to go. To lenghten the slots, in the original plates, in the direction they need to be lenghtened, will only jeopardize the integrity of the movable latch plate. JD & Co. should be made to make new plates and obsorb the costs involved. I made the suggestion to them to make me two new plates as I designed and I would relocate the drilled and tapped holes myself. Still no responce from JD.