Kubota hydraulic cylinder seal replacement, "slide jig" and "correcting jig"

[joea99]

If your local shop doesn’t do honing you need to keep searching. All competent hyd repair shops hone cylinders.
I can hone as small as .125” up to 12” bore x 18.5’ long. If your cylinder is binding then likely you have a dent or burr, or hyd rod or barrel is bent. Honing a significant dent will only trash the honing stones.
If you think the cyl is mechanically binding you need to pull all the seals and dry fit the parts before reassembly to find the issue.

All I have is the internet search to find them. Any ratings are to be taken with a teaspoon of salt.

As someone in the trade, do you know of any in my area? Zip 12401 would be a good round number for radius. You are a good 4 hour drive and I doubt you would do it while I wait and shipping would be a bear. Polar or Grizzly.

 

[RickB]

Mooradian Hydraulics

Mooradian Hydraulics

www.mooradianhydraulics.com

I lived in Dutchess County for over 50 years. Mooradian's is your go-to hydraulics shop.

Powertech is on RT 28 north of Kingston. They may not do onsite cylinder repair at that location but are close enough to you to be worth a call.

https://www.google.com/search?q=powertech+hydraulics&ie=UTF-8&oe=UTF-8&hl=en-us&client=safari#trex=m_t:lcl_akp,rc_f:rln,rc_ludocids:462310814211850898,ru_gwp:0%252C7,ru_lqi:ChRwb3dlcnRlY2ggaHlkcmF1bGljc0jwsYrI5YCAgAhaHhAAEAEYABgBIhRwb3dlcnRlY2ggaHlkcmF1bGljc5IBGGh5ZHJhdWxpY19yZXBhaXJfc2VydmljZaoBHBABKhgiFHBvd2VydGVjaCBoeWRyYXVsaWNzKAA,trex_id:YWaWgb

 

[RickB]

How hot is hot? What's a good way to heat the oil?

Vegetable oil or plain water in a small fry daddy or similar. Don't take it back to the kitchen after. They are good for heating bearings too, or anything requiring a semi-press fit.

 

[RickB]

Call me lucky or skilled, likely I’ve rebuilt more cyls than most people can count. I’ve only been rebuilding cylinders full time for the last 45 years. Heating the seal is only a waste of time and energy.

This is more about how a relatively inexperienced person can be successful and less about how great you are at it.

 

[wdchyd]

Best to ask your local rental and construction companies who they go to most. There’s tons of good small shops and the best ones don’t need advertising but are well equipped for their repeat customer base.

 

[joea99]

It's an hours drive to the closest outfit I know of so far that actually talked to me and does the work in house. They offered to evaluate it at no charge, if I bring it in, so I may go up there next week.

Meantime, I'm just tip toeing ahead.

Got the old seals off and did a "dry fit" the rod and piston in the cylinder (tube). Seems OK, there were a couple spots that hung, but that seemed to be only my not keeping perfectly "square" to the tube. Repeat passes did not show a repeat of the hang.

The tube, externally, checks straight.

Don't have any v-blocks, but do have a Brown&Sharpe steel straight edge. Feeler gauge shows max of .002 which is far from the Kubota "replace" spec of .0098, if I read the WSM correctly.

 

[joea99]

Went ahead and installed all the seals, using the slider and pusher jigs I made up. Worked great. Did not heat up the seals at all. Did not use the re-sizing jig as I did not want to take more time to smooth the inside and did not want to chance buggering up the sealing face. So just used a hose clamp and some flexible thin plastic as I did not have any aluminum cans around.


So far, operates in both directions, and no leaks. Not stress tested, but seems OK.