Gehl 553 lift cylinder leaking at seal

[Gehl 553]

I have a Gehl 553 telehandler with a leaking main lift cylinder (1 of 3 ) on right side of main boom. I have heard from mechanic that you have to loosen a valve on bottom of cylinder in order to dismantle cylinder. He also said if you are not careful a bolt will shoot out. Does anyone here have any experience with this cylinder. I would like to rebuild it myself but I do have a need for more info. Thanks

 

[MarshallPowerGen]

The cylinder will have a holding valve you will need to remove before you can take the gland nut off. We always used our longest ratchet and put a bucket or oil drain pan over in case it wanted to shoot off across the shop. Some will blast off and some will just unscrew without any issue.

You get real nervous when they start spinning out easy and then suddenly tighten up at the end...

 

[Gehl 553]

Hey thanks for the information. Another question or two: 1. Should I leave bottom of cylinder attached to lift 2. How much pressure will it take to pull apart?

 

[MarshallPowerGen]

It's been a couple of years since I've worked on one of those, but IIRC you should be able to leave the bottom half attached and do it on the machine if you don't have a cylinder bench/pipe vise available. Don't remember if you can get the top end clear with the forks on the ground, or if you'll need some C-channel to safety the other side with the boom up (and a crane/forklift for additional backup doesn't hurt).

No clue what you'll be up against as far as getting the upper pin out and the gland nut loose. Some are a hammer, pipe wrench and gland nut socket. Some take a torch, sawed off sledge and a .498 air hammer.

 

[Gehl 553]

I have a feeling that I should go ahead and tackle this job, hope it goes good. I will probably need torch,sledge hammer and .498 with my luck.
I think the local mechanic told me to raise up and block boom up. That is the normal way they do it. He talked like once you get holding valve and gland nut, upper pin
etc.. off , it still takes a come along or something to pull the rod out of the housing. Is that normal for a large cylinder?
As far as a crane for backup I have a TC33d 33hp New Holland tractor with loader ha ha. I will probably drive lift back to my shop 10 miles this weekend. Hope I don't lose to much fluid , could I use regular pipe plugs to block off cylinders or are they a special thread? Thanks again for all your answers

 

[MarshallPowerGen]

Most likely will be JIC or flat face fittings versus pipe. Come along/chain hoist is pretty normal for getting the rod out. Is it leaking while running, or only while operating the boom?

 

[Gehl 553]

Hello again, It leaks when running ,even for a while after engine shut down. I would guess about a drop per second. Maybe I will tie something around it to catch fluid.
Too bad diesel is 6 bucks a gallon here in eastern Ia. I don't know how much hydraulic fluid is. I did some research on fittings ,wow that's a can of worms.
I will drive over to the jobsite today and PB blast all my pins and such today, check oil, coolant levels, tires before I make the trek home (shop) this weekend.
Might take some pics also. Thanks again and have a good 4th

 

[Gehl 553]

I took some pics ,The picture of the bottom of cylinder shows bolt with an Allen screw and lock nut. I backed out screw about 4 turns and then went back in all the way, then I noticed fluid coming out, which let me release pressure on cylinder. Then I was able to compress cylinder enough to get the top of it out of the top bracket.
Now does that lower bolt have to be removed? (the one holding Allen screw) It has about a 3/4 inch nut around a bolt with an Allen screw inside of the bolt.

 

[Gehl 553]

I just want to clarify my last question (now does lower bolt have to be removed?) I should have asked, Is their anything else that has to be removed before I pull the main rod out of the cylinder? Note: I did remove the bolt ,locknut and Allen screw . It had a couple of 0-rings that were not in very good shape. Makes me wonder if that was what was making it leak out the top seal. Here is a pic of ibolt/Allen and 0-rings. You can see middle one is tore.

 

[Gehl 553]

Well I got cylinder apart, pretty good story . 1. Had to make a pipe wrench 2 foot square tube with a double 520 chain welded to it (see pic) and 8 foot of pipe over it. 2. Had to heat up 6 inch cylinder cap with rosebud oxy/acetylene and the only thing that would budge it was a long barreled air hammer with 175psi of air pressure. 3.. Then I still could not get rod removed from cylinder. 4. beat on it and heated up and cooled down for a week and used acetone and brake fluid mix to try and loosen it. Hooked up cable to a dead man pulley and winch still it would not budge. Last ditch effort I removed cylinder from lift and hoo ked it between my tractor and truck with my wife driving tractor and finally with me beating with sledge hammer and her pulling it finally came apart. The only mistake I made was I messed with allen screw on the safety release valve. After I put new seals in I will have to try to get the allen scew adjusted correctly. Does anyone have any advice on doing this ?

 

[Gehl 553]

Well I might as well finish this story. I got to looking at my cylinder after I got it apart and cleaned I could see some rust ,got a flashlight and I could also see pitting. Decided to take it to my local machine shop. They advised me to get it replaced. Told me it they could make one for $685.00. Does this sound reasonable? I had already bought seals at local Gehl dealer, now mach,shop won't guarantee unless I use they're seals. What would cause all the rust , machine was always left outdoors on the jobsite winter and summer for the past 15 years.

 

[Jonas302]

The $685 sure sounds very reasonable are they cutting the barrel off and reusing the good parts you could always save your seal kit for the other side

Might need to change hyd oil it may have collected mosture from condensation or even though the tank lid if heavy rain and melting snow even the way the lift cylinders point up could let a little bit of water in though the rod seals

Your chain wrench isn't much to look at but it held up to all that force

 

[Gehl 553]

Glad you liked the wrench, I just learned to weld kind of. They are just going to order new pipe and I imagine will use mounts ect. off the old one. I am kind of planning on changing fluid and filters, is there any way to check for moisture in fluid? From what I dumped out of barrel it looked excellent not milky. Hope I don't have to replace anymore seals. Lift has only 2200 hours but is probably 20 years old. I suppose condensation over the years takes a toll on seals. Has anybody else had this problem and what do I have to look forward to in the future? I will try and get some pics of the inside of the barrel.

 

[Txhayseed]

Well you can not reset a holding valve to spec with a test bench. I would measure the other side and set the one you loosened to those measurements. Should get you pretty close. There is no rime or reasons to cylinders. I have some come apart with out issue and like your ordeal I have some fight to the bitter end. I had one not long ago I couldn't get apart on a skytrak. Pulled it off and sent to our cylinder guy and his machine could not get the gland loose. Ended up welding a bar to it. Heating it up to the surface of the sun and using a 18 ton excavator to push down on a 12' bar. It busted loose finally. But Ive had same cylinder on numerous other machines come loose with a gland nut wrench.. Just the way that cookie crumbles