Help on disassembling a cylinder for JD model 90 loader

[wateka]

I'm trying to disassemble the cylinder on my JD model 90 loader to replace the seals. So far, I cannot figure how to get it apart and wonder if I need a special tool. A picture is attached, and when I put a wrench on Ring A and turn, both Ring A and Ring B turn together and all it does is rotate those parts in the cylinder. Based on the threads shown in the picture, Ring B is screwed into Ring A (or vice versa). Without ruining the threads, how do you hold one ring still, while turning the other?

 

[kennyd]

Welcome to TBN!

The .pdf from JDParts is to big to attach, but if you register at www.jdparts.com for free you can get it yourself, there is a quick tutorial linked in my signature that can help if needed. Just put 90 in the search box.

Here is a screenshot of the parts breakdown ( I think its the correct cylinder anyway-I am nor familier with that machine), I hope this shows what you need.

 

[Willl]

Is there paint covering spanner wrench holes in ring "B" (12 and 6 o-clock position) ?

 

[wdchyd]

If it's not too late, the best way to hold the inner gland is to power the cylinder with hydraulics on the extend position.......it will push on the gland out and keep it from turning.....allowing you to tap on the retainer with a punch to loosen it (or use proper spanner)

I usually do this before taking the cyl off the machine.......and after you completely reassemble, with the cyl on the machine, pressurize it out the same to hold gland and tap the retainer tight (while under pressure)

there are no threads on the gland holding it in the cyl barrel, just retaining lock rings under the gland (push gland in to expose them)

 

[wateka]

Thanks for the replies, but no luck so far. @wdchyd, reinstalling it and putting it under a load is still an option, but the cylinder is already off and I'm an hour away from the tractor until next week. @Willl, I thought that was going to be the answer as well, until I stripped the paint off - see the new photos - those were just paint drips. @kennyd - thanks for the parts diagram, which is spot on, but JD doesnt make it clear how that retaining nut is to be removed.

 

[Coyote machine]

Maybe it is removed from internal detents, only accessable once you remove what's removable now from the housing. Other choice is to take it to a shop where they've done this type of cyl dis-assembly many times with the right tools. Couldn't cost too much to undo it, then you repack it with new seals and away you go.:thumbsup:

 

[Oliver1655]

- I use compressed air to move the piston. This will allow you place pressure on the retaining ring & loosen the locking ring.
- Once the retaining ring/cup is removed, I will apply a short burst of compressed air to pop the piston/rod assembly out. If a short burst does not work, DO NOT keep pressurizing the cylinder. Instead:
- Anchor the base to your work bench & use a simple 1,000# hand cranked cable winch fastened to the other end of the bench to pull it out. I also attach a piece of rope around the rod which is anchored to the base with around 6" of slack to keep the piston/rod from flying when it does come loose.
- I will also use my digital camera & take a photo of the way the seals/retainers on the piston are configured if it is not a common setup. It is no uncommon for the rebuild kit to not be identical to the original packing due to changes in technology. Most kits will have a diagram to work from.

Wish you the best,
John.

John

 

[wdchyd]

- Once the retaining ring/cup is removed, I will apply a short burst of compressed air to pop the piston/rod assembly out. If a short burst does not work, DO NOT keep pressurizing the cylinder.

John

Using compressed air to hold cyl out i OK......but DO NOT use air to pop out the piston assy......You're gonna get hurt or the person standing in the room

after the retainer is unscrewed from tapping with a punch, you need to use an aluminum/brass rod to tap the gland head in about 3/4" to expose the round retainer ring tucked inside a groove in the cyl barrel.......then the gland head/piston assy can be pulled out (come-along or hammer)

 

[cooterdude]

lightly tap the outer ring with a dead blow hammer all the way around the circumferance of the head the resulting shockwaves will clean any rust / pain out of the threads use a brass drift in the notches in the ring to tap the ring the direction you want it to go lefty loosy righty tighty once you have the outer ring off of the gland you have to push the gland backwards into the barrel to remove the large circlip holding the gland in the barrel if you have the jd kit alredy it comes with an orange ring you can fit into the barrel to make removal of the piston /gland easer