Kubota B2710HSD front axel sheared off.

[dieselscout80]

I used an accumulator I had around and did my own kit. Mine, I believe, has a 0.75L volume and it's preloaded with 50 bar which is a bit too much. Ideally, it would be 30 to 40 bar.

There are some kits on Ebay, located in Europe though.

Something like this, you just need a Tee and an hose. Hydraulic Accumulator 0,16 - 1 Liters with ball valve Free Charging | eBay

View attachment 2307189

Do you think one that’s just 0.5L work rather than the 0.75L?

 

[ptsg]

Do you think one that’s just 0.5L work rather than the 0.75L?

Most kits offered use the 0.5L. Should be plenty for the cylinders on these compacts.

 

[M59]

I believe you are most likely correct, but to know correct counterbalance weight you'd have to know the front axel load capacity, the existing load on the axel with the FEL empty, the effective weight of the load you're putting in the bucket which will vary based on how high you raise bucket, and the effective weight of your counterbalance which will vary with distance from rear end of tractor. In addition to this it would be advisable to know the available load capacity of the rear axel as you will be shifting weight to this pivot point. As mentioned in prior post my intension is in future, when possible, to attach my 505 lb chipper to rear accepting it may not cancel an excessive load on the front axels, but will help. I, however, do need to look up the load capacity of my rear axels. I should add if you descend a long steep hill you will transiently transfer the load to your front axels in which case the counterbalance will work against you.

Petdoc, Your going to need more data than what you mentioned because the loader arms and piston attachment points are between the front and rear axles. You've entered the arena of FEA/ Finite Element Analysis as it applies to structures. Way beyond the conversation on TBN.

As an aside, I asked and received an answer directly from Kubota America engineering, when I was interested in going from 6 ply to 10 ply tires for front on my M59. Kubota would NOT give me the specification for front axle design load. My interest in knowing the design load was to determine if I could unintentionally overload any part the front axle system because of the higher load bearing capability of the 10 ply tires.

 

[5030]

Far as hydraulic accumulators are concerned. The reason for the cost is vessel construction and what the vessel has to withstand pressure wise before structural failure contributes to the cost. That vessel has to withstand great pressure and pressure spikes so it has to be designed for that scenario, consequently the cost and I'm not sure it has to be of great volume either as all it's doing is absorbing the pressure sike and dampening the reaction and if I installed one, it would be in the main loader supply port on the loader valve itself. Kind of similar to a pressure relief vessel on a water supply line to mitigate 'water hammer' which is essentially the same thing but at much less pressure.

Concerning front axle failure of the outboards, I believe it has to do with the choice of bearings Kubota uses. I've always thought they should be radial roller bearings, not ball bearings, but I'm not an engineer and come to that conclusion from observance of the outboards, not from any other experience.

I do know from observance that hydraulic dampening units, even on large commercial forklifts aren't all that large, in fact they are quite small but I do know that charging one is beyond the capabilities of most people simply because the average user has no way to charge one with inert gas (hydrogen or argon) to the required pressure of whatever the installed in system is rated for, which would be somewhere around 2100 psi or whatever that particular tractor is rated for concerning hydraulic pressure. In my case I could using an inert compressed gas welding bottle and it's pressure gage. Normally. a fully filled gas bottle will register about 2300 PSI, which is more than adequate to pre charge one.

 

[PETDOC]

Petdoc, Your going to need more data than what you mentioned because the loader arms and piston attachment points are between the front and rear axles. You've entered the arena of FEA/ Finite Element Analysis as it applies to structures. Way beyond the conversation on TBN.

As an aside, I asked and received an answer directly from Kubota America engineering, when I was interested in going from 6 ply to 10 ply tires for front on my M59. Kubota would NOT give me the specification for front axle design load. My interest in knowing the design load was to determine if I could unintentionally overload any part the front axle system because of the higher load bearing capability of the 10 ply tires.

I do understand that the calculations I refer to are best done by rocket scientists that received an A in college physics. I am not and I did not. All I need is a ball park idea of where I am vs axel load capacity. In the Messick's YouTube I attached in earlier post the speaker referred to the opacity of Kubota on axel load capacity, but indicated they get it with spec sheets for tractors they buy. You might give them a call as they seem very helpful.

 

[ptsg]

I do understand that the calculations I refer to are best done by rocket scientists that received an A in college physics. I am not and I did not. All I need is a ball park idea of where I am vs axel load capacity. In the Messick's YouTube I attached in earlier post the speaker referred to the opacity of Kubota on axel load capacity, but indicated they get it with spec sheets for tractors they buy. You might give them a call as they seem very helpful.

Doesn't it have a tag similar to this one on my tractor, saying the permissible axle loads?

 

[5030]

Interestingly, neither of my M9 Kubota's have that sticker anywhere on them and to my knowledge, never have but, the maximum permissible axle loads are plainly spelled out in the owners manuals along with implement limitations.

 

[ptsg]

Interestingly, neither of my M9 Kubota's have that sticker anywhere on them and to my knowledge, never have but, the maximum permissible axle loads are plainly spelled out in the owners manuals along with implement limitations.

I don't think the manual for my tractor lists it either but I do have that info on the title of the tractor as well.

 

[M59]

I do understand that the calculations I refer to are best done by rocket scientists that received an A in college physics. I am not and I did not. All I need is a ball park idea of where I am vs axel load capacity. In the Messick's YouTube I attached in earlier post the speaker referred to the opacity of Kubota on axel load capacity, but indicated they get it with spec sheets for tractors they buy. You might give them a call as they seem very helpful.

Even if the manufacturer provides a written limit for front axle load how are you going to know when you have reached it given the mounting points of the FEL and their relationship to load transmission to both front and back end of the machine. That is exactly why, after Kubota America's engineer refused to provide me with a hard number, I realized knowing the number would not tell me what I needed to know, which is "What is the weakest link between the load carried by the bucket of FEL and the rest of machine. This is a FEA problem. Is it the loader arms, is it the loader arm pins, the bushings, etc, etc, etc.

You found a weak link ( the spindle to hub attachment ) but why must be answered if you are trying to craft a solution that assures a non repeat of this failure and there are many reasons for metallurgical failures.

 

[5030]

I don't think the manual for my tractor lists it either but I do have that info on the title of the tractor as well.

I have no titles for either of my Kubota's, just bills of sale. Must be different where you reside. Same with all the implements, bills of sale, only.