731 Tilt cylinder disassembly

Hiram · Feb 4, 2026

I have a Bobcat 731 that I have owned for several years. Recently it started leaking from the tilt cylinder. The leak seemed to be coming from the cylinder's lower hydraulic fitting. I replaced the o-ring and it got significantly less, but then I used it for a larger job and it started leaking seriously again. It only seems to leak when the machine has been used for long enough to get the oil hot. I'm thinking it may be leaking from the seal around the gland nut which would present as coming from the fitting since they are right next to each other and the fitting is lowest. I got a re-seal kit and removed the cylinder from the machine. I could not figure out how to get it apart. The gland nut just rotates, it does not seem to be threaded. The lower hydraulic port is in the gland nut. There is a slot about 3/16" wide and 1 1/4" long in the cylinder body approximately 3/8" below the gland nut. It seems to have two ends of a ring in there, but no way to get it out. The cylinder is original Bobcat equipment made by Cessna. I took it to The Bobcat dealer and they can't figure out how to get it apart either.

I'm hoping someone here knows how to get it apart. If not, it's looking like I'll need to replace the cylinder.

brdgbldr · Feb 4, 2026

Hiram said:
I have a Bobcat 731 that I have owned for several years. Recently it started leaking from the tilt cylinder. The leak seemed to be coming from the cylinder's lower hydraulic fitting. I replaced the o-ring and it got significantly less, but then I used it for a larger job and it started leaking seriously again. It only seems to leak when the machine has been used for long enough to get the oil hot. I'm thinking it may be leaking from the seal around the gland nut which would present as coming from the fitting since they are right next to each other and the fitting is lowest. I got a re-seal kit and removed the cylinder from the machine. I could not figure out how to get it apart. The gland nut just rotates, it does not seem to be threaded. The lower hydraulic port is in the gland nut. There is a slot about 3/16" wide and 1 1/4" long in the cylinder body approximately 3/8" below the gland nut. It seems to have two ends of a ring in there, but no way to get it out. The cylinder is original Bobcat equipment made by Cessna. I took it to The Bobcat dealer and they can't figure out how to get it apart either.

I'm hoping someone here knows how to get it apart. If not, it's looking like I'll need to replace the cylinder.

It looks like Bobcat actually still has the seal kit for that cylinder. Part number: 6514736

Not sure what you mean by the lower gland nut. The gland that comes off is the one that the rod runs through. A photo would be helpful. The other end should not come off and there are no seals there. If it is leaking at that end then that cylinder may be shot. You could possibly try to weld it shut if that is your leak.

The exploded view of that cylinder should help. I have never worked on that specific cylinder so I’m not sure of how it is held together. Pretty sure that the one end screws off though.

Here is a link to the parts catalog:
https://partscatalog.bobcat.com/

Hiram · Feb 4, 2026

Yes, I got the seal kit from Bobcat. The cylinder is still with the dealer so that's why I haven't included any pictures so far. Yes, the gland nut is the part the rod runs through. Unfortunately, it only spins and does not separate. It is definitely leaking from the rod end of the cylinder, the other end is welded. All indications are the leak is from either the seem between the cylinder and the gland nut or the hydraulic fitting. I'm thinking that because the leaking isn't significant during short periods of operation, but when doing larger jobs the leaking is significant; the leak is coming from the seem once the cylinder and oil heat up.

The leak is the main issue, but the cylinder is also leaking past the piston. When the bucket is left tilted all the way back at the end of the day, by morning it's flat on the ground. The cylinder definitely needs a seal kit - if it can be gotten apart.

Hiram · Feb 4, 2026

In looking at the Bobcat part catalog, here's a link to the right cylinder:

https://partscatalog.bobcat.com/?pa...-Hydraulic+System/0005-Tilt+Cylinder+(Cessna)

If you look at part #2 - the main cylinder, it shows the slot in the lower part of the cylinder. Part #14 looks to be a locking ring inside the cylinder holding the gland nut in. I just can't see how you're supposed to release it or get it out.

I'm going to jump in the truck and go over to Bobcat of the Rockies and see if the old guy they were expecting today came up with anything. They said he's been working on these things for 26 years (sounds middle aged to me) - only problem with their theory is that this machine is 20 years older than that.

spitzair · Feb 5, 2026

It's actually not threaded on there, it has a retaining ring that you see in that little slot you talked about. You need to dig one end of that ring out then pull the whole ring out as you turn the head of the cylinder. Once the retaining ring is out the whole head, shaft and piston assembly comes out... I've done it way long ago and it can be a bit of a bugger to get the retaining ring started on its way out but once started it comes apart quick and easy. Here's the page in the manual that shows how it's done. Hope this helps.

jameslmarchetti70@gmail.c · Feb 5, 2026

This method is the best and only way to do it. Shown above

Hiram · Feb 5, 2026

Thank you all. Yesterday afternoon I found a video on how this is done. I went back to the dealer and they had not been able to get it apart. I offered to show them the video and they weren't interested. I retrieved my cylinder, came back to my shop and got to work.

This is called a square wire retention system. The Cessna cylinder I have isn't the only place it's used. Cylinders like this have been shown in videos on Kubota, John Deere and Cat as well as the Bobcat I have. The procedure shown in the above post is the correct way to go. What they don't make obvious is there is a hook bent onto the end of the square wire. This hook is what allows the wire to be pulled in to form the retention ring and then pushed out when the time comes.

What confused everyone on my cylinder was the hook had broken off so the gland just rotated with nothing else happening. I noticed the hole in the ring track and made a pin to fit which allowed me to push the square wire out.

Now the two challenges will be: 1. The seal kit is not the right one for this cylinder. The main piston cup is 1/2" thick and there's nothing in the seal kit that thick. and 2. finding a new square wire for the retention ring.

Thanks again for the help. Y'all have been more help than you will ever know. I've been a member here for going on 6 years. I read a lot and usually find the answer to my questions without having to ask, and other folks questions where I could contribute are usually answered before I see them, so I don't post much.

Y'all have a great day, and Happy Skidding

jameslmarchetti70@gmail.c · Feb 5, 2026

Hiram said:
Thank you all. Yesterday afternoon I found a video on how this is done. I went back to the dealer and they had not been able to get it apart. I offered to show them the video and they weren't interested. I retrieved my cylinder, came back to my shop and got to work.

This is called a square wire retention system. The Cessna cylinder I have isn't the only place it's used. Cylinders like this have been shown in videos on Kubota, John Deere and Cat as well as the Bobcat I have. The procedure shown in the above post is the correct way to go. What they don't make obvious is there is a hook bent onto the end of the square wire. This hook is what allows the wire to be pulled in to form the retention ring and then pushed out when the time comes.

What confused everyone on my cylinder was the hook had broken off so the gland just rotated with nothing else happening. I noticed the hole in the ring track and made a pin to fit which allowed me to push the square wire out.

Now the two challenges will be: 1. The seal kit is not the right one for this cylinder. The main piston cup is 1/2" thick and there's nothing in the seal kit that thick. and 2. finding a new square wire for the retention ring.

Thanks again for the help. Y'all have been more help than you will ever know. I've been a member here for going on 6 years. I read a lot and usually find the answer to my questions without having to ask, and other folks questions where I could contribute are usually answered before I see them, so I don't post much.

Y'all have a great day, and Happy Skidding

Glad that worked out for you. What bothered me is if that hook may be broken off and as you said it was. Good we have that enginuity to make things work. Thanks for the follow up.

Hiram · Feb 6, 2026

One of the local hydraulics and cylinder shops had the square wire and was quite familiar with this type of cylinder. The 1/2" ring is a wear ring not a seal, so it's not as critical as I thought. For $200 he'll give it back to me tested and ready to go - provided there are no other issues. Since I was already fighting it to get the piston off the rod, I figure it's a deal. It should be ready in a few days.

Hiram · Feb 18, 2026

I got the cylinder back from the hydraulic shop for $250. The seal kit that I was assured by the dealer was the right one was 70% wrong. The cylinder seems to be in good shape, and I have no reason to believe it isn't, but I was unable to test it yesterday because of a dead battery. If it's not one thing, it's another.

731 Tilt cylinder disassembly

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