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

[joea99]

only thing I can add is we use a small square (1” x 1”) square of thin shim stock (.010”) or a piece of alum soda can to put under the worm on the hose clamp to protect the seal when tightening the clamp. Works perfect and quickly.
No need for all this special tool stuff.
While boiling seals and sticking hyd rods in a freezer works it’s not necessary.

I've seen some instructions that use electrical tape for that, but I like the aluminum can idea better.

 

[RickB]

While boiling seals and sticking hyd rods in a freezer works it’s not necessary.

Stretching a poly piston seal at room temperature is very risky. If you have never damaged one by not heating/softening it you are just lucky or haven’t done enough for the odds to catch up with you. Heated seals return to their original size easier as well.

 

[joea99]

Stretching a poly piston seal at room temperature is very risky. If you have never damaged one by not heating/softening it you are just lucky or haven’t done enough for the odds to catch up with you. Heated seals return to their original size easier as well.

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

 

[wdchyd]

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.

 

[ROUSTABOUT]

You can cut a piece of soda can and have a ring around it under the clamp if you want. But take it off before you install. Take something and clean out the entrance. Piston never hits that area anyway.

 

[joea99]

Thanks for all the advice. I will probably follow it (I can get pretty stubborn), but first I'd like some opinions on the condition of the cylinder. The piston itself, metal part anyway, look fine.

I posted this on its own in this forum, but it has not response as yet. I guess even if it is questionable, at this point, I may as well give it a try? I cannot "feel" and ridges, using a makeshift feeler, a stick of wood with a finish mail though it.

Any thougths on the condition of the cylinder? Honing was suggested. No nearby shops can do that, all farm it out.

 

[fried1765]

Messicks, a large Kubota dealer, provided these instructions on how they install seals without the two jigs.

Read attached pdf file

Dave M7040

There is NOBODY quite like Messick's!
They are the absolute best!

 

[joea99]

There is NOBODY quite like Messick's!
They are the absolute best!

Always my first choice.

 

[joea99]

Any thougths on the condition of the cylinder? Honing was suggested. No nearby shops can do that, all farm it out.

I modified my "scratch tester" with a unbent paper clip on the end of a stick. I cannot feel suggestion of a "catch" or "bump" at any point in the cylinder.

I'm a thinkin' it's good for now.

 

[wdchyd]

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.