Cylinder Cap Removal Help

[linckeil]

Hey Guys,

New to the site. Hoping you can give me a hand. I recently picked up a used log splitter. It's a monster and goes right through the gnarliest wood I can find. I have no clue on its age or the manufacturer. Anyway, I am going through it changing all fluids, fixing some broken welds, and dealing with a few minor leaks.

I am trying to take apart the piston to replace the seals. Iv'e dealt with hydraulics before and have always been able to unthread the packing nut, but not on this piston I've never seen one like this before. Instead of trying to explain it, check out the pictures:

http://www.plowsite.com/showthread.php?t=81927

You can see a hole in the center of the slit. This is a machined hole about a quarter inch deep. This machined hole spins with the cap (which spins relatively freely). This is the only hole. At the bottom of the slit, appears to be a square piece of stock that sits in the grove. I think this stock holds the cap on. Unfortunately, the stock is kind of mangled and only a quarter inch of it is visible and I cannot get it budge. When spinning the cap, I removed a tiny piece of what I think was originally part of this stock. I drained all the fluid from the cylinder hoping that would help, but it has not. How do I remove this cap?

Can anyone identify this splitter, or the type of the piston it has? An exploded of the piston (or at least the type of the piston) would help greatly in understanding how to disassemble it. Please help. Thanks.

 

[Dirthog]

You have to remove the ring in the hole on the side of the tupe reach in with a small screw driver or something and get under the end of it then just turn the head till you can remove the whole ring then the head will come right out

 

[linckeil]

thats what i figure, but like i said, i can't move this piece of stock in there, and only about a quarter inch of it is visible. i drained all fluid and turn the cap while trying to dislodge it, but it won't budge. any suggestions?

 

[Wayne County Hose]

What you have in there is a square piece of wire. At the end, it is bent 90 degrees. This bend goes into the cylinder cap. If you turn the cap and the wire won't move, then the bent piece is broken. Here is what I do when this happens. Turn the cylinder so that the open part where the wire is points up. Spray some thin penetrating oil into the groove. Do this a few times and let it sit overnight. Then, take a small center punch and tap the wire lightly until you can get it to move. Get the end to the opening. The end you want will have a taper on it, the other end will be the broken piece. You may need a little help, but you can stick a small pick under the tapered end and tap the wire around with the center punch until it starts to come out. Another thing that works too is to turn the wire until you come to an end and can see the cylinder cap. Now turn the cylinder cap until you can see the indent where the end of the wire would go. Now get the end of the wire to that part and pound it down with a small punch so that when you turn the cap the wire turns with it. This requires patience but you can do it. Just take your time and think it through.

Good luck, Andy

 

[linckeil]

Thanks for the tips Andy.

I actually played around with it a bit last night. I was able to dislodge that piece of square stock/wire. I removed it, but it was only about an inch long. I then rotated the cap and another inch long piece of stock came around to the slit and I removed that too. But I think there is still more square stock in the grove that I cannot access. I gently used the piston as a slide hammer to try to pop the cap off once I removed all the stock that I could, but it would not come off, so I think there is still some more in there. How much would you expect to be in there? Like I said, I removed about 2 inches, but the total circumference of the cylinder is 14 inches. If there is more in there, how do I remove it? I tried snaking a coat hanger through the channel, but whenever it encountered resistance it would just bend.

 

[Wayne County Hose]

There is definately more in there. It goes all the way around. Try turning the cap and looking into the slit. You will find an indent where the wire would go down into the cap. Take a piece of the broken wire, put it in a vise. Now hammer it over until you get a 90 degree bend. snake that bend into the indent and turn the cap. This should help force out the broken pieces. This is weird, I have never seen the wire broken up like that. This will take some finesse.

 

[linckeil]

thats what i was thinking, but i didn't want to risk loosing another piece of stock/wire in the cap, but i think that is really my only option at this point....

this design seems like a big headache.. why not just make a threaded cap like every other piston i've ever worked on????

 

[dfkrug]

this design seems like a big headache.. why not just make a threaded cap like every other piston i've ever worked on????

A very good question! SMC loaders and newer JD loader cylinders use this
method. I have also owned and worked on internally-threaded caps,
externally-threaded caps, and internal snap-ring retained caps. I wonder
how many methods are out there.

 

[Wayne County Hose]

thats what i was thinking, but i didn't want to risk loosing another piece of stock/wire in the cap, but i think that is really my only option at this point....

this design seems like a big headache.. why not just make a threaded cap like every other piston i've ever worked on????

Ha! Another moron engineer trying to save 50 cents for his company and make a name for himself. I always believed that any engineer should have to work on the stuff he would be designing for at least 2 years before he can design anything. Don't get me wrong, most engineers are great. But, like any profession, there are good and bad.

 

[linckeil]

ok, so it worked... i took an inch long piece of the stock/wire i was able to remove and bent, shaped, cut, and grinded it to just the right form. i spent about 15 minutes doing this, and once i had it right, it only took about 2 minutes to remove the remaining stock/wire. what a relief! thanks for the tips andy.

so now that the piston is all apart, theres only about 4 seals in the entire assembly. i'm gonna head to a local hydraulic shop saturday morning with the disassembled piston and see if they can get me the necesary replacement parts. are there any good online sources for parts you guys use?

based on the pictures, can anyone identify the manufacturer or model of the piston? there are some numbers stamped on it, but no name is given.