B6000 - Hydraulics

[modds]

Hello. I have purchased a B6000 Kubota last year and it was running pretty good, except on the F.E.L. the tilt on the bucket would not hold it's weight (under load, it would slowly give way to gravity). It was not a big deal, and I've used the tractor for some jobs, but I'm looking to fix/solve this issue and have brought it into the shop. The up/down of the F.E.L. was always working fine (recently it has stopped lifting up consistently, but will still go down normally).

Any suggestions on where to start? I have no experience with tractors/hydraulics.

Thanks,

 

[North Idaho Wolfman]

You could be having an issue with either or both the cylinder seals or the valve assembly.
Given it's age I would say bite the bullet and rebuild both.

 

[sclb]

You could be having an issue with either or both the cylinder seals or the valve assembly.
Given it's age I would say bite the bullet and rebuild both.

Could you tell us more please.
I too have a B6000 with rear hydraulics which sag slowly after raising and think this is a similar problem. What's involved with the rebuild?

 

[X32]

I have a B6100 loader backhoe and rebuilt all of the hydraulic cylinders on both ends (11) and from what I could tell they were never replaced since original and all of the edges were completely gone I was surprise it worked as well as it did after looking at the seals.

As to what's involved simply remove hydraulic cylinders remove end caps pull apart rod from cylinder (I used two trucks) and get rebuild kit from Kubota you'll need 3 types 6 will cost about $17 each and 5 will cost about 50 bucks each and each rebuild will probably take you 10 minutes but if you never did it before the 1st one probably take 30 minutes by the time you get through one or 2 you'll feel like an expert, it's very easy. I would also suggest that you wet sand all of the rods with 200 grit wet sandpaper and any places that you see rust do the same in a perpendicular motion to the action

 

[ShaunRH]

Be very careful sanding hydraulic cylinder rods. If there is no rust, don't sand!

Most are chrome coated and if you sand or damage the chrome, you get rust! Don't make your problem worse.

Rust is usually better dealt with using a chemical agent and use polishing agents, not sandpaper. You should be polishing the metal, not damaging it.

If you are getting a major rust problem and have to store the unit for a significant period outdoors, wrap the exposed cylinder surfaces in oil cloth and wax paper around the cloth, then cover with a tarp. This will keep the rust away from the surfaces and not affect the hydraulic fluid. If it's regularly used, you don't need to do that as the rams are usually fairly self cleaning, the seals taking all the abuse!

P.S. The only time I recommend abrasives is if you ding the rod and need to level it out. You have to fix this fast or you can strip the seals almost immediately!

 

[Drewdaman]

Rust is usually better dealt with using a chemical agent and use polishing agents, not sandpaper. You should be polishing the metal, not damaging it.

Thanks for providing this suggestion, and can you please clarify exactly what a "polishing agent" is, and where I can buy it? I recently bought a BH and all the cylinders are very rusty, see attached.

Thanks in advance,
Drew

 

[North Idaho Wolfman]

Use a soft Scotch Brite and Bar Keepers friend to get the rust off, and if very stubborn use CLR, then strips of heavy cloth and brasso or any bare metal polish, and then consistently wax or grease coat the rams in the future to keep rust at bay.

 

[Kennyd4110]

Thanks for providing this suggestion, and can you please clarify exactly what a "polishing agent" is, and where I can buy it? I recently bought a BH and all the cylinders are very rusty, see attached.

Thanks in advance,
Drew

That cylinder looks to far gone to save (to me)-the wiper seals won't stand a chance.

 

[ShaunRH]

That cylinder looks to far gone to save (to me)-the wiper seals won't stand a chance.

I agree that could be very deep pitting and the cylinder would need to be skimmed and re-chromed. For the price of that operation on smaller cylinders, it's usually cheaper to buy a new rod or an entire new cylinder. If you are a decent machinist and have access to a lathe capable of handling it, you can do the repair yourself. That's probably less than 0.1% of the tractor using community though.