Backhoe Kubota BH77 bucket won't stay extended

[CanuckPT]

Latest update. The local dealership I took the bucket cylinder to replaced the seals in the cylinder but found that there was a lot of "pitting" - quoted me $580 to have it repaired. I called Marshall Machinery in PA where I bought the tractor and they've gone to bat for me!! They had the cylinder UPS'd to them and have had it sent out to a local hydrualics guy there for repair so the good news is, it appears that the problem is being takend care of by the dealership I purchased from.

However, both dealerships had mentioned that pitting is often a sign of water in the hydraulic fluid. This tractor only had 19.8 hours on it when I took delivery and has been garaged since I bought it in October except for 1 night.

Is there any other reason that pitting would occur? I'm now freaking out wondering if there's a systemic problem with water (if there is any water at all) that's eating away at other vital parts of my tractor that only has 32 hours on it!!

 

[Carl_NH]

That doesn't sound right - water in fluid - usually water in the oil makes it milky.

Even still, many BH sit out for months at a time with the chromed cylinders exposed to the weather and no adverse effect.

Two things - since Marshalls has this now and you have 17 hours to the 50 hour change (it is 50 hours on your machine right?), have them ship Super UDT and the filters along with the cylinder back to you?

Especially if Marshalls said it could be water - then you might get a good deal on SUDT and filters.

At the end of the day, I think it was a bad rod assembly because your whole machine would be impacted by bad oil I would think

Carl

 

[CanuckPT]

That doesn't sound right - water in fluid - usually water in the oil makes it milky.

Even still, many BH sit out for months at a time with the chromed cylinders exposed to the weather and no adverse effect.

Two things - since Marshalls has this now and you have 17 hours to the 50 hour change (it is 50 hours on your machine right?), have them ship Super UDT and the filters along with the cylinder back to you?

Especially if Marshalls said it could be water - then you might get a good deal on SUDT and filters.

At the end of the day, I think it was a bad rod assembly because your whole machine would be impacted by bad oil I would think

Carl

Good suggestion Carl - I'll ask them about it.

 

[1savoy]

I agree with all of that. It would be worth doing the 50 hr service and drain the hydraulic fluid as well. See if you get water before the oil drains. If you do get water then you will have to figure out where it is getting in or if it has been there for awhile. Like Carl had mentioned, it seems like all the cylinders would be affected if it was water in the system. I wonder if possibly just a problem with the coating on that particular cylinder rod and not water in the system.

 

[CanuckPT]

It would be great if that were the case 1savoy!! Isolated incident sounds appealing to me!!!

 

[Carl_NH]

Canuck,

I realized I focused on the shaft being pitted - but is it the cylinder / tube insides that are steel that are pitted instead? That would damage the seals in short order and cause this condition.

Still think this is isolated to that one alone otherwise all would behave similarly.

Let us know how you make out with the fluids also.

Carl

 

[CanuckPT]

Canuck,

I realized I focused on the shaft being pitted - but is it the cylinder / tube insides that are steel that are pitted instead? That would damage the seals in short order and cause this condition.

Still think this is isolated to that one alone otherwise all would behave similarly.

Let us know how you make out with the fluids also.

Carl

The dealers both said that it was the cylinder itself that was pitted and was tearing up the seals. I truly hope that you're right & it's just the one cylinder that's affected. I've not noticed any cloudiness in the hydraulic fluids but I'm going to check for sure! I did as the dealer I purchased from about shipping some SUDT - they're looking into it..... I just want my tractor back in working order!

 

[CanuckPT]

Great news! My backhoe cylinder was repaired by Marshall Machinery (in PA where I purchased it) & it arrived today! It's all reinstalled, fluid topped off (I will do my 50 hour service early & replace all the fluid with SUTD when I get the chance to pick up some fluids & filters. Back in the saddle, now to get some seat time in!! Thanks for your advice!!!

 

[1savoy]

Glad to hear you are back in action :thumbsup::thumbsup: Good job getting it taken care of. Thanks for letting us know how you made out.

 

[Carl_NH]

Canuck,

Good for you - seems Marshall did right by you as well. Now use it and let us know how it works and hope this is the end of the issues.