I am considered about the support on my frame for my L3301 with a 4672A backhoe (which has it's own hydraulic reservoir and only use the rear PTO) that is currently attached. I would feel more comfortable knowing that if I installed the support frame, it would eliminate any frame bending issues. Since I do not need to loop in the hydraulics, I think all I have to do is install the frame while the 4672A backhoe is already attached to the tractor. Has anyone ever had this configurtion and installed a subframe on a L3301 with a 4672A backhoe?
Question about installing a sub frame on my L3301 with a 4672A backhoe already mounted to the tractor
- Thread starter ChiefKubby
- Start date
B4672A backhoe right? 3PH backhoe with PTO operated hydraulic pump?
I have the larger sister, a BL4690A on my B2910 (generally install it when I need it).
I think normally a NON 3PH backhoe is mounted on the subframe. How are you thinking of doing this?
Not sure how easy it is to make an extra addition to the tractor frame that will be effective, if the backhoe is not mounted to that subframe.
If you share a few more things about what you are thinking to do, then someone with knowledge might be able to give you some suggestions.
Regardless of what you end up doing, MAKE SURE you have a heavy duty top link bracket installed if you are using the backhoe attached to the 3PH.
I have the larger sister, a BL4690A on my B2910 (generally install it when I need it).
I think normally a NON 3PH backhoe is mounted on the subframe. How are you thinking of doing this?
Not sure how easy it is to make an extra addition to the tractor frame that will be effective, if the backhoe is not mounted to that subframe.
If you share a few more things about what you are thinking to do, then someone with knowledge might be able to give you some suggestions.
Regardless of what you end up doing, MAKE SURE you have a heavy duty top link bracket installed if you are using the backhoe attached to the 3PH.
Do you have photos of your setup? Backhoe attached to the subframe? Back when I was thinking of adding a backhoe, I mounted a heavy duty top link bracket. If you don't have to hook up the top link, because it has a subframe, don't worry about it. BUT if you do use a top link with your setup, build or try and buy one (don't think they sell them any more).
It bolts to the back like normal but it wraps around the top of the transmission and bolts up there. The bend is reinforced.
It bolts to the back like normal but it wraps around the top of the transmission and bolts up there. The bend is reinforced.
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There is no subframe on a 3PH backhoe.
The backhoe attaches to the top link bracket, and the lower part to the 3PH arms.
Edit: But I think there is something added to the frame on my B2910, as the mechanic gave me something that he replaced, that looked like brackets used on the frame of NON backhoe tractors. Never figured out what they were, but still have them.
North Idaho Wolfman
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dirtydeed
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It sounds like the OP is considering if he should install the BH subframe (for BH77) in order to "stiffen" the frame? I don't believe he was thinking it would connect (4 point) to his existing backhoe...just provide additional frame support?
Then again, I could be totally off base.
Then again, I could be totally off base.
I thought he was considering fabricating a subframe and somehow adapting it to the 3PH backhoe…
North Idaho Wolfman
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Neither of these would make any sense to leave the BH on and try and do, right?
ChiefKubby, just update us on what you are thinking of doing...
Bottom line, if the hoe is not attached to the sub-frame and you expect the sub-frame to protect your tractor, well, it might help a little to not crack the bell housing but will most likely add extra stress to the lift arms and top link also likely the whole backside of the transmission case.
Many people run a 3ph backhoe without a sub-frame successfully but there are a few who have had costly repair jobs too.
Bottom line, if the hoe is not attached to the sub-frame and you expect the sub-frame to protect your tractor, well, it might help a little to not crack the bell housing but will most likely add extra stress to the lift arms and top link also likely the whole backside of the transmission case.
Many people run a 3ph backhoe without a sub-frame successfully but there are a few who have had costly repair jobs too.
When you buy a subframe, part of it is attached to the backhoe itself and replaces the 3PH mounts. Here is an example of one. I don't know which model or tractor it's for, but pretty much like what I have on my B2410 and BH70-X. The parts on the left bot to the backhoe directly.
torch
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B7100HSD, B2789, B2550, B4672, 48" cultivator, homemade FEL and Cab
The manual for the B4672A backhoe is clear on the need for a suitable FEL (including the associated subframe) to prevent damage:
"The Kubola B4672 - 6 foot Backhoe and the Kubola BL4690 - 7 1/2 fool backhoe have been designed to mount on approved Kubota Tractors as shown on the next page, equipped with a Kubota approved Front Loader."
"The Kubola B4672 - 6 foot Backhoe and the Kubola BL4690 - 7 1/2 fool backhoe have been designed to mount on approved Kubota Tractors as shown on the next page, equipped with a Kubota approved Front Loader."
Yes, that is correct because the subframe is attached to the FEL mounts and not directly to the tractor frame in that area. On mine it is attached at the very front and to the HST case in the rear, and then clamped to the FEL brackets in the middle.
I have the 2 bottom lower links of the 3 point hitch attached to the backhoe(4672) and the top link is the rectangle shaped orange bar, see attached pictures. Because the Top Link is locked in with two pins, I locked Float Control, so I do not raise or lower the backhoe. A lot of the comments on the internet says I should install the subframe, Some people say that they would do it on a small macheine but there is not a need to do it on the l3301. Your thoughts would be apprecaited?
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Yes I wanted to know if I needed to stiffen the frame becasue of the size of the backhoe or is the set up I have OK? I called a couple of Kubota dealers including Messicks and they were not sure if the backhoe would get in the way of the subframe.
My thought on this, take it or leave it, is that while in use, all the stresses from the backhoe are concentrated on the HST case at the three points it is attached, where with a subframe, all that stress is transferred to the entire tractor. Any bit of slop at those attachment points amplifies the stresses, and a backhoe puts a LOT of stress when digging.
What is less expensive, the subframe kit, or a new HST case? Are 3PH backhoes even made anymore?
What is less expensive, the subframe kit, or a new HST case? Are 3PH backhoes even made anymore?
I am trying to attach a listing in PDF form of Kubota heavy duty top link brackets. I do not see you tractor listed though.
Perhaps your tractor is not listed because the 3PH backhoe you have was used on smaller tractors and not offered for the L series?
The worry is possible damage to your transmission case. Pretty big risk maybe, I do not know. I do know that I got a lot of use from my BL4690A 3PH backhoe over the years. Naturally it mounts just like you show in your photos. AND I have a HD top link bracket installed.
My guess is that a HD bracket is not offered for your L series model, because a 3PH backhoe was likely not offered either. Apparently your tractor uses a subframe type backhoe as standard. (EDIT: I do see other L Series models listed though.)
Take your chances and live with the results. I think that sums it up. Not sure anyone here will be able to say you are home free using that backhoe on your tractor without risking damage. Even given it is a larger tractor than many using the same backhoe, with a HD top link bracket. (EDIT: since other L series models are listed for HD top link brackets, this would concern me)
torch
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B7100HSD, B2789, B2550, B4672, 48" cultivator, homemade FEL and Cab
The manual I have for the B4672A predates the L3301, so that tractor is not mentioned. But it does list the L3300, which was very similar in size and weight. The L3300 required a heavy-duty top link bracket to be installed, together with a FEL.
Have you asked your dealer if there is a HD top link bracket needed or available for the L3301? There is no point in reinforcing the underside of the tractor if you are simply going to risk breaking the top link bracket off anyway.
As the L3301 was intended to be mated to the BH77, which attaches via subframe, I suspect there is no HD bracket available.
They sure do make em still. Work great as long as you understand the limits of your equipment. I’ll be in the same boat this spring as I’ll be shopping 3ph backhoe attachments also. Don’t plan on it being on the tractor unless in use.
Most catastrophic issues I’ve seen or herd have been from operator error. Older equipment being worked to hard for to long. I’m sure there have been cases of weak design or defected parts but you can’t treat a backhoe attachment like real backhoe or mini Ex.
For my needs and many others going the full sub frame kit from Kubota if that’s even a part I could get for a m7060 plus a Kubota BH the cost would just not be worth it. If after I’ve got and used my 3ph Backhoe I feel it needs some added support I’ll do something like old and tired did.
Most catastrophic issues I’ve seen or herd have been from operator error. Older equipment being worked to hard for to long. I’m sure there have been cases of weak design or defected parts but you can’t treat a backhoe attachment like real backhoe or mini Ex.
this looks like a great idea and also beefs up the area I’ve seen and herd most damage caused.
For my needs and many others going the full sub frame kit from Kubota if that’s even a part I could get for a m7060 plus a Kubota BH the cost would just not be worth it. If after I’ve got and used my 3ph Backhoe I feel it needs some added support I’ll do something like old and tired did.
North Idaho Wolfman
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Here is a good video on it.
Adding a reinforced top link only adds minimal support.
It's not going to keep it from breaking it in the middle.
Adding a full subframe is the best bet.
Adding a reinforced top link only adds minimal support.
It's not going to keep it from breaking it in the middle.
Adding a full subframe is the best bet.
Thanks for all your advice, I have to do more investigation. I wish I knew for certain that the sub frame would fit the 4672 backhoe.