Hydraulic Piston Question

My latest toy has a 6ft loader on it. The piston that rolls the bucket is starting to leak hyd fluid out the end of the piston. It looks like I can get the nut off with a spanner, question is do you have to take the entire piston apart to repair the leak, if its a complete seal I would think there is no other way. Any suggestions appreciated.

scotty

• Hydraulic Piston

I bought an antique combine one time that must have had 20 hydraulic cylinders and seems like there were 4 or 5 different ways to get at them. I had never done hydraulics before but by the time I had them rebuilt I was pretty good.

Repair is not that hard and if you have a reasonable mechanical aptitude you should do fine. If your local IH house can't get seals for you, you should be able to go to a hydraulics parts jobber and get them just by presenting yours to them.

Agreeing with info in other posts, there are 2 sealing mechanisms: 1 seals the innards from the outtards, and 2 seals the piston that does the work.

With a nut on the end, you should be able to back it off and unscrew it. once you pull the nut out there should be a (outter seal) on the bottom of it. With the nut off, you should be able to plush the movable shaft (containing the piston) toward the open end of the cylinder and the piston will come right out. There should be a screw or another nut holding the packing of the piston and it should be right there in your face. Depending on the type unit (mfgr's choice) something unscrews so that the piston and shaft can be removed from a cylinder. Be sure to pay particular attention to the "packing" as there is sealing packing and then there is pressure back -up packing and you need to insure that the pressure back-up is on the right side of the seal or the first time you power her up you'll blow your seal.

Common sense goes a long way on this job and you can do the job for around $35. Might as well do the other side while you're at it. If this side needed it, won't be long before the other will too.

Good Luck,

Mark

PS. On really large cylinders (like on a 100 hp sized front end loader lift cylinders) I had to use a come-a-long to push the piston/shaft back in....and be sure to soak the packing in hydraulic fluid prior to installation. Want things as slippery as you can get them....and don't forget to "vent" the other end of the cylinder when trying to push a piston back in....it's a bear if you don't.

Thanks

scotty

Now seriously are you saying there is large nut around end of cylinder where ram enters the cylinder. You might just try tightening that nut if it is as I described. Some of those cylinders rely on tightness of the big nut keeping seal tight. It will probably only be a short term solution. When the ram is fully extended are there any marks on the ram? If there is you probably will need to take the whole cylinder to a hydraulic shop. What happens here is forign objects get where they shouldn't be as you tip bucket and score the ram. Those score or scratch marks damage the seal. This doesn't happen often, but is also quite hard to avoid 100% of the time. The seals can also just fail with time. And yes cylinder does have to come apart to replace the seals. Hydraulic shops can also repair a lot of marks on rams. By the way on terminology the piston is inside on the end of the ram. If you are doing this there are also seals on piston inside, they will not leak externally. It will just allow oil to bypass the piston and the bucket be tipping towards the dump position if they are bad. Any questions you know what to do.

You indicated to me before the loader my have been not in use for awhile, thus the seals may have just dried out, that is the simple fix.

scotty

I think you probably meant to say your rod seal is leaking. In either case, you will have to remove the rod, piston, and bearing. Most likely you'll have to get an entire kit to replace your leaky seal, while it's apart just replace all of them.