Kubota BH75 bent bucket cylinder rod

[sergeant285]

Does anyone have the exact specs on the bucket cylinder for a BH75 backhoe? I bent the rod digging in some rocks. A new cylinder from the stealership is almost $1000. I can get a new rod machined, but if I can find a matching cylinder for cheaper, I’d just as soon replace it.

I know Kubota upgraded the cylinders at one point from the 30mm rod (what I have) to 32mm rod. Mine is marked with 7K50143011. I’d like to match up a cylinder from Magister or Surplus Center that upgrades to the 32mm (1.25”), but I want to get the order right. If I can get this one apart I can get the outside diameter, pin diameters, etc. from the bent cylinder, but I need to know the overall length and the extended and retracted lengths.

If anybody has already found the right cylinder and can just point me to what to order, so much the better.

I have attached photos of the markings on the cylinder for clarity.

 

[Roadworthy]

You may save yourself some grief taking it to a local hydraulic shop. They will in all likelihood be less expensive than Kubota and probably have options for you.

 

[sergeant285]

I tried one of the only two hydraulic shops within a reasonable distance. The machine work to machine a new rod makes repairing the cylinder about half the cost of a new cylinder, and I’d still have a 30mm rod. That said, I was able to determine the correct specs on the cylinder and have a new one on the way from Magister for a couple-hundred bucks. I’ll update once it’s installed, but the extended/retracted lengths are the same, as are the pins, stroke, etc., so I’m hoping it’s a drop-in replacement.

 

[sergeant285]

Oh, and the additional upside, other than cost, is I’ll have a 1.25 (32mm) updated rod instead of the weak 30mm rod that bent.

 

[ruffdog]

Another thread:

Bent bucket cylinder rod on BH75......Need Help

 

[ruffdog]

This guy straightened his cylinder:

 

[dfkrug]

This guy straightened his cylinder:

Impressive video. I never did it that way. For me, it was the 20T press.

Wear your eye, hand, and nut protection!

 

[sergeant285]

This guy straightened his cylinder:

That’s seriously ballsy. That piece of wood shooting across the shop says a lot. I would also be worried about it leaking long term, but that might well get you back up and running to finish a job. Thanks for posting.

I think my rod might be too bent for that approach. Even if it isn’t, I’ve already ordered the replacement, and I have the boom and dipper cylinders off for seals while I’m at it. Would be interesting to try, though.

I’m just hoping this aftermarket cylinder works well, and this post can offer an alternative to the stealership’s cylinders or expensive machine work when someone else encounters this apparently all-to-common issue.

 

[ptsg]

I also bent the bucket cylinder on my homemade excavator. Granted, it was kinda of a dumb stunt while fighting an huge eucalyptus tree stump.

Even though I have plans to build another stronger cylinder, I managed to straighten this one within 0.2mm.

 

[TMGT]

That's one thing I like about my M4711 backhoe (Bradco 611), the bucket cylinder is 3in with a 2in rod! Very stout.

 

[sergeant285]

Sorry for the delay on an update. I got my backhoe back going, and I had projects. I wound up using a 2x18 cylinder from Magister. $232 with shipping and taxes, so less than 1/4 the price of factory. It works perfectly. I decided to go cross tube instead of tang ‘cause it was cheaper. The top was 8mm too wide and the bottom was 2mm too wide. I just trimmed them up with my bandsaw, filed them smooth and polished them, and they fit perfectly. I thought about painting the cylinder to match, but the black is growing on me.

The SKU on the cylinder is “WCT 2x18”. It takes an SAE6 connector, so I got those from Amazon.com. Once I got the tubes trimmed, it went straight on with no issues and worked perfectly. It’s a larger rod as well, so no more undersized 30mm junk.

If you bend one of these, I highly recommend putting in a little sweat equity and getting an aftermarket cylinder.

Pics are from before the SAE6 connectors came in. The factory connectors worked with lots of teflon tape, but they leaked a little. The SAE6 connectors are perfect.