i'm trying to rebuild the bucket and stick cyls. on a cat track hoe. i have the rams out of the tubes but can't break the nuts loose that hold the pistons on the rams. i tried a 1" impact wrench didn't budge. heated the nut, tried the impact again same result. tried a torque amplifier still no luck. anybody have an idea? rick.
one thing that is possible is that there might be a set screw on the gland nut that needs to be removed first? What size of track hoe are you working on?
If they're like our old Cats, they could be put on with 2500 ft-bls or more. We used to take them to a dealer who had a hydraulic bench to loosen them. I do know of a machine shop that uses a 12' cheater bar and wrench heads cut out of plate. The bar works most of the time.
your right i have already removed the set screw and ball lock.
Then I think your gonna need a cylinder bench as RobVG is correct those torque's on the nuts can be quite high...
right before i left work today i cut a wrench out of 3/4" plate and beat it with a 16# sledge, moved it about 1/4" i'm hoping some more heat and sledge tomorrow and i win! but this is the small one only 3.5" nut the big one has about a 4.5" nut. this winter i'm thinking we need to build a hyd. bench if we can find a model.
A bench would be a cool project. But how often would you use it? I put our pistons back on with a 1" impact and loctite. Haven't lost one yet and you can get them off easily the next time you have to repack.
What size of air compressor do you have? Without enough air you cant get all your force out of that gun. What size of track hoe are the cylinders from? Is there a lock pin or screw that needs to be removed? Are the threads spiked? Some of these nuts are torqued to a very large amount (500-3000ft/lbs). Remember that it takes 1.5 times the force to break the nut loose than to install it. If you can, pin the rod end back on the machine, and use another machine to push your breaker bar, or rig up a bottle jack. Mark the nut to threads for re-torque purposes before removal. (**CAUTION if you are not careful the ROD MAY BEND**) You may have to take it to a cylinder shop as they will have a cylinder press to break the nut loose.
Hi rick ,you really should get someone with a cylinder bench to take that nut off and more important put it back on .nuts newer hoes are tight a 315c for example torque to 4700 ft lbs. and I guarantee if you dont torque it to that it will come loose over time
bolt torque I dont know what machine you have but CAT cyl nut torques are very high with out the biggest on hyd cyl benches only cutting the nut off will remove them THE BIG D
i think this is maybe a E200 trackhoe don't know for sure, the owner just droped them off for rebuild. we do alot of ag cyls. but they are easy compared to these. i got to work today and the nut on the bucket ram finally gave up and came loose the big one is still a problem. rick
RobVG, the guy that opened this shop i work in is famous around here for making his own tools and machines so making a bench is right down our line. do you know where i can get a picture of a good style bench?
cylinder rod nut A 200 size machine is going to be very tight our Kobelco on the arm is around 7000# for that size and they only go up from there and on a excavator if they are not tight they will come loose you do not want that to happen when it comes loose and starts making metal in the system it gets very expensive!! We have had to clean out more that one system because of that happening.
Not a very good picture but here is what one looks like. This one also has a hone. Edit: Maybe that's not a hone? Assembly side? The basic idea is you have a hydraulic cylinder that acts like a connecting rod. It pushes against the wrench you made which acts like a crank journal. Please disregard what I said about assembly. These other guy's are right.
Better off taking the cylinder to a hydraulic shop and having the proper torque put on the nut when installing. Their machine will easily remove the nut as well. Remember, Cat lock nuts are designed to be used only once and thrown away after being removed. New nuts are expensive, but not nearly as expensive as a complete hydraulic system cleaning and repair when one comes loose -- as they tend to do more often than not. Hydraulic cylinder resealing seems like a very easy job, but it isn't. The tools required are big, and expensive. Some manufacturers use different methods of retaining pistons and head glands, which use smaller components, smaller tools, and less torque on the fasteners. But Cat does not. I've been on the wrong end of way too many home-done hydraulic cylinder repairs, that is, cleaning up someone else's screwup. They nearly always turned out to cost a very great deal more shortly after. This is, I admit, on bigger cylinders, but the same holds basically true on the smaller ones too. Good Luck!
surfer-joe i voiced my thoughts that we should send these rams out to valtech in st.louis to get the nuts broke loose but was promptly told get that idea out of my head just find a way to get the nuts loose because thats why they bring 'em here. sometimes it's like talking to a wall if you know what i mean. so i'm thinking if we are going to do this more than once we need to build a better way. thanks for everyones help and ideas. rick
Can the rod(s) be removed from the main lift cylinder tube if the tube is left pinned onto the machine at the base?
T Gun the cyl. is at our shop on the floor, i have the ram out of the tube just can't get the nut to come loose.
sawz5, I understood that, my question was more generic. I have a similar problem with my Linkbelt. I need to repack the seals in the main lift cylinders and I am trying to figure out if I can get the cylinders apart without taking the tubes off the machine. I don't have any way (ie... another excavator) to lift the cylinders in and out of position. Back to your problem with the rod nuts, I found this website http://www.fastorq.com/ they seem to have all kinds of neat tools for similar types of problems. Those guys in the oil patch have similar challenges trying to take huge equipment with big rusty fasteners apart all the time. Perhaps if your boss wants to be able to handle these types of cylinders he might pony up some dough to buy the proper tools instead of letting you beat your head against the floor trying to solve the problem. Just curious, is the customer being charged by the hour or was he given a quote for the job?
we charge by the hour but have a very librel adjustment system, as for your problem i did two cyls. on atrackhoe this spring by taking them loose at the boom end, laying them down on a sawhorse took the headplates loose, pulled the rams out, put new seals in, put the rams back and everything went real smooth.( the machine was in the building so we had an overhead crane)
just to let everyone know the cyl. are back togather. made some heavy wrenches and used a torque amplifier and 10' bar. thanks to all for the advice. rick
Thanks for following up. :thumbsup