hydraulic cylinder repair

[pelhamjeff]

Hi, guys and happy new year. I'm pretty sure the cylinder on my splitter is bypassing. I am trying to decide weather to farm out the repair or do it myself. Mine is the kind with the four long bolt running the length of the cylinder, not that welded up kind. Do normal people repair these?

 

[triptester]

What you have is called a tie-rod cylinder. You can reseal it if you know the brand and can locate new seals. To dismantle the cylinder remove 4 nuts on the tie-rods and the cylinder will pull apart. Once the rod end cap and rod are removed almost all the seals are exposed. Care must be taken to ensure no surfaces get scratched.

I would try to test the cylinder first for leakage. Place a small jack between the wedge and push extend the ram so it almost touches the jack . Remove the hose at the rear of the cylinder and plug that opening. If the seal leaks the jack will slowly push the rod back into the cylinder.

I you decide to take the cylinder in for rebuild get a fixed price quote to see if the rebuild will cost more than a new cylinder. Most farm supply stores and Northern Tool will carry tie-rod cylinders.

 

[Mike Van]

Jeff, why do you think it's "bypassing"?

 

[cabinman]

What you have is called a tie-rod cylinder. You can reseal it if you know the brand and can locate new seals. To dismantle the cylinder remove 4 nuts on the tie-rods and the cylinder will pull apart. Once the rod end cap and rod are removed almost all the seals are exposed. Care must be taken to ensure no surfaces get scratched.

I would try to test the cylinder first for leakage. Place a small jack between the wedge and push extend the ram so it almost touches the jack . Remove the hose at the rear of the cylinder and plug that opening. If the seal leaks the jack will slowly push the rod back into the cylinder.

I you decide to take the cylinder in for rebuild get a fixed price quote to see if the rebuild will cost more than a new cylinder. Most farm supply stores and Northern Tool will carry tie-rod cylinders.

Trip is spot on ,.Test your system first,..I bought a new 5in x 30in cylinder for my splitter off an excavator for 300,00 bucks,. NASA quallity,.. orginaly cost 1200.00,..the mechanic said it was bad,..turned out it was the valve,..the guy took a bath, and I got it for 25 cents on the dollor, It cost a little more than a cheep one But , its top shelf

 

[Swamp Yankee]

If you don't already have one install a pressure gauge in the pressure side line. Easy to do and not very expensive. If you don't want to leave it in the line set it up with quick connects. Now you'll always be able to check what the pump is putting out, your relief valve setting, and if your cylinder seal(s) are good.
If you don't think the cylinder is performing to snuff check the return side as well. A valve spool not fully opened, a crimped or blocked hose or clogged filter in the return side can eat up your system performance in a hurry.
Good luck.

 

[JeffHK454]

By "bypassing" do you mean loosing oil from one side of the piston to the other , around the gland packing or at end caps?

Are there leaks or poor performance?

Tie rod type cylinders that have had a bunch of use tend to swell the tube and pass oil around the piston about the same time they develop leaky end caps.

 

[pelhamjeff]

I think the cylinder is bypassing for a couple of reasons. With the rod extended more than about halfway, you can grab the clevis and wiggle it side to side or up and down a fair amount. Also, from the day I got it running, there is a steady stream of fluid that leaks out around the end seal on the return stroke. I'm talking about a serious leak. I have it run down a little peice of 1" angle and collect in a measuring cup and I think it hits the 3-cup line in 20 minutes. I put this thing together for about 65 dollars including the fluid, just having fun. Yesterday, it couldnt split this easy peice of oak, and instead of straining, the engine rpm was probably dropping by 500 or so. I estimated where the seals were, based on how far the rod had extended, and the cylinder was noticably hotter in that small section than any other part of the system. My valve and pump were normal temperature. I verified this with an infrared thermometer. I should also say that this situation didnt happen suddenly, but it wasnt really gradual either. No, I dont have a gauge in the system anywhere and I dont have any hydraulic experience. That little test with a hydraulic jack is a great idea that I plan to try out tommorow. If the seal is as weak as I think it is, I may be able to push the rod in without a jack. Thanks for all the info/advice, and I will gladly read any other responses!

 

[triptester]

The rod seals in the end cap will allow play and leak when they need replacement.
The piston seals by-passing as you say in only one area may indicate that there is a problem with more than just the seals. There may be a problem with the cylinder walls that seal replacement may not solve.

 

[cabinman]

The rod seals in the end cap will allow play and leak when they need replacement.
The piston seals by-passing as you say in only one area may indicate that there is a problem with more than just the seals. There may be a problem with the cylinder walls that seal replacement may not solve.

tap the google button, maps, tsc,....And go pick up a new cylinder, Seriously,. If your fixing it your self, It might be cheaper, If not, forget it, providing you do have a bad piston/bore, just make sure its not the valve,..If you decide to go another step on your own , Tear it apart and look for your self,.Inspect the parts carefully, Use a flash light in the bore, check the piston for scratches, etc, HEY maybe a seal kit will fix you up, Expereince is just that, not somthing you read out of a book /chat line,....

 

[mga]

they aren't hard to do at all. here's a web site that explains what to look for:

http://www.maintenanceresources.com/referencelibrary/ezine/caseyhyd2.html

and, when you need parts, check out one of our member's sites:

http://www.cylinderservices.net/catalog.asp?prodid=511343

chances are your cylinder only needs new seals all around. very easy to replace.