Back Hoe Maintenance

Lloyd_E · Oct 20, 2013

Issue started last year but I should address it soon. When using the hoe there is a lot of movement with the brace supports mounts/arms. I tightened all the major nuts/bolts many times and they still wiggle loose. Yesterday(first time use this year) I noticed a metal nut stop(prevents nut from spinning) had a crack in the weld. So my question is: when repairing the crack should I weld up all of the contact points/support arms to the unit. The holes in the brace arms and main unit are probably oval now. Should a new bushing or fix be done here as well?

TIA

cabin kioti · Oct 20, 2013

I have a CK30 HST with a 2375 backhoe on it ,I had the same problem and tried double lock washers,,special nuts that were not to come loose they (DID) lock tite and a number of fixes that didn't work. I finally welded the braces to the sub frame two years ago and that fixed the problem. I check the nuts every so often and they are tight, I am not sure a new bushing would help the problem but it wouldn't hurt.

Coyote machine · Oct 20, 2013

I would start by disassembling some of the more stressed area bolts/nuts an see what the holes look like. If elongated, then you'll have a better idea of what is happening. Welding the 'bar' which locks the frame braces is the factory design, but welding other parts may cause additional stresses and possible breakage, depending on what you decide to weld.
Can you post pics of what exactly you plan to weld? Are you referring to the stabilizers which swing down to the ground on either side of the hoe?
Do you grease ALL the zerks regularly?

IXLR8 · Oct 20, 2013

I talked to one Kioti dealer who said the the bolt on braces for the BH mount were done for shipping reasons. He welds up all connections/braces that are made with bolts that never come apart. He said he has been doing it this way for over 10 years with no issue. YMMV

DK35vince · Oct 20, 2013

Weld the braces
I had the same problem.
The sub frame braces constantly came loose.
Welded the braces years ago. Problem solved.

Coyote machine · Oct 20, 2013

News to me. If we're talking about just the subframe braces it makes sense. What exactly did you guys weld to what?
Thanks,

CM

Lloyd_E · Oct 20, 2013

Sub-frame braces only.

Fuggley · Oct 20, 2013

Never had any frame wobble problem with my kb2375..... but I'll pay closer attention now.
I'd like to see a pic of the dealer weld too if someone can post one.

Coyote machine · Oct 21, 2013

There are no dealer welds, just factory welds holding the grey frame brace nuts in place. They use a small bar welded to the brace to keep the nut from backing off.

I believe the guys in the conversation above are talking about welding the actual grey shipping braces to the hoe frame to reduce/stop any movement. I can't say for sure, since I haven't seen any pics of the actual weld points, HINT-> HINT.

Lloyd_E · Oct 22, 2013

Sorry the images are a little soft...

Image 2161 shows the bolt head stop and the crack. 2158 is the right side, 2160 is the left side of tractor.

The diagonal gray support is the brace. I would assume you weld where the brake meets the sub-frame(lower right) and the hoe station (upper right).
I would also weld the station to the sub-frame, just below the step - where there are two bolts.

In image 2161 you can see the amount flex of the brace by the rust on the hoe station.

lloyd

Coyote machine · Oct 22, 2013

Lloyd,
thanks for the detailed pics. They show where the problem is. In the 1st pic are you going to weld a stop for each nut below the step or weld the orange station piece to the grey frame?

Lloyd_E · Oct 22, 2013

If others could post their solutions that would be great. My thoughts are to weld all contact points:
brace to hoe station unit, brace to sub-frame and hoe station unit to sub-frame unless someone can see a reason not to.

I also wonder if the brace to hoe station unit and brace to sub-frame would work without welding the sub frame to the hoe station unit.

The holes are probably oval now...

kraftykeltic · Oct 22, 2013

The bolts are used to clamp the pieces together, coarse thread bolts do a lousy job of clamping pieces together. A better solution is to use fine thread bolts, they may be difficult to find in some areas, but they can increase the clamping force, stopping movement of the parts they are holding together.

chubby · Oct 25, 2013

Just a thought, engineers are pretty sharp and I believe if they thought frame to station should be welded it would have been welded. Don't get me wrong, mine has so much flex the hoe seat hits the top liink holder. Every 100hrs I retorque hoe, loader and mounts. Each time fewer bolts are loose. Just reaching the 500hr mark and I am sure one or two will be loose. In the hoe manual it list bolt torque spec's. The frame to station bolts are up there in the 400 lbs range. If you don't have a torque multiplier go rent or borrow one. A piece of pipe on your torque wrench is not an answer. This frame and station sure do flex and one must assume this is the design the engineers planned. I use the tractor mainly as a back hoe and would guess half of my hours are using the hoe. My hoe only comes off to move what little snow we get. But if you have never torqued to spec's not guessing but checking in the high numbers then I would believe you will never have the machine "tuned" to its potential.

DK35vince · Oct 25, 2013

chubby said:
Just a thought, engineers are pretty sharp and I believe if they thought frame to station should be welded it would have been welded.

My opinion is the sub frame is bolted together more due to shipping/handling reasons than anything else.
I bought my backhoe still on the crate and installed the sub frame/backhoe on my tractor myself.
The sub frame comes completely disassembled for easy shipping.
Welding the braces will not hurt a thing. I welded mine and wouldn't hesitate to do it again vs messing with the constantly loosening bolts.

IXLR8 · Oct 26, 2013

DK35vince said:
My opinion is the sub frame is bolted together more due to shipping/handling reasons than anything else.
I bought my backhoe still on the crate and installed the sub frame/backhoe on my tractor myself.
The sub frame comes completely disassembled for easy shipping.
Welding the braces will not hurt a thing. I welded mine and wouldn't hesitate to do it again vs messing with the constantly loosening bolts.

This is what my dealer told me, that the sub frame/braces come in pieces and are bolted together strictly for shipping/handling reasons.
It will be about a month before I am at my dealers again, if he has any BH frames welded up I will take pictures and post them.

Lloyd_E · Oct 26, 2013

chubby said:
Just a thought, engineers are pretty sharp and I believe if they thought frame to station should be welded it would have been welded. Don't get me wrong, mine has so much flex the hoe seat hits the top liink holder. Every 100hrs I retorque hoe, loader and mounts. Each time fewer bolts are loose. Just reaching the 500hr mark and I am sure one or two will be loose. In the hoe manual it list bolt torque spec's. The frame to station bolts are up there in the 400 lbs range. If you don't have a torque multiplier go rent or borrow one. A piece of pipe on your torque wrench is not an answer. This frame and station sure do flex and one must assume this is the design the engineers planned. I use the tractor mainly as a back hoe and would guess half of my hours are using the hoe. My hoe only comes off to move what little snow we get. But if you have never torqued to spec's not guessing but checking in the high numbers then I would believe you will never have the machine "tuned" to its potential.

This is exactly what I am experiencing... "Don't get me wrong, mine has so much flex the hoe seat hits the top liink holder." I may try to find fine threaded bolts/nuts before I go the welded route. I am worried the bouncing/flex may cause other issues.

Thanks all for the info...