Hydrulic cylinder leaking again.

I've paid the hydraulic 3 times to fix the leak. I've used factory o rings to repair it twice, The insanity has to stop. Doing the same thing 5 times and getting the same results has to be the definition of insanity. I'm trying something different.

Hydraulic shop strongly advised against using any glues to fill in holes in rod saying the glue will fall out under 2000 psi and then cause problems else where. Well my rod looks good, I'm thinking my problem may be at the end of cylinder where after running a brake home it appears to have some scratches. I'm filling the scratches with devcon, a liquid steel someone on YT recommended. If the glue falls off, good chance it will be pushed out the end of the cylinder where it appears to be leaking from.

Going to let the devcon dry for 24 hours before I sand it smooth with brake hone. The pic shows the devcon. Only going to replace only the one O ring that I suspect is leaking. I hope the insanity stops by trying something different. Also think because the two O rings on the piston were damaged when I removed it from cylinder and somehow the scratched on the inside of they cylinder was the reason. Forgot to say how much fun it was getting the new o rings on the piston. They would roll 90 when installed. Then I had to use two screw drivers to twist it back properly, what a pain.

Post back if it leaks. Then, I might looking for a new cylinder.
geo.

geo.,

Hard to tell in pic if a 'C' clip holds the block in, if so, like mine the tube as expanded letting fluid past the block.
Mine were a lot worse than what yours look, I went the same route you did (could have bought 2 sets)machine shop to square up the grove, all new seals, worked about a hr., then started spiting out the 'C' clips grove rounded.
I figured the cylinder wall was too week, ended up cutting a 2" muffler pipe then 'U' bolted it hard to the block still working.

Is that the piston in the lower pic. ? Those type of seals don't look like the best design is it leaking past the piston and drifting down ?

Or is it leaking at the gland which is the part that goes into the cyl. at the top. The outside and inside O-rings or quad rings on it should have back up rings.

The part that leaks are one of two I rings. The one in contact with rod. Other in contact with cylinder. I'm thinking the second I ring in contact with cylinder is my leaker.

My end uses a wire not a clip.

I wonder if they are using the correct type of seal for that spot ?

Mike, I purchased rebuilt kit from terramite, they are the same as the hyd shop uses. I'm thinking there has to be something better than a simple o ring. Something like used on piston, a two part o ring that what will expand under pressure. Willing to try anything. It's very simple to take cylinder apart without removing hoses from cylinder. geo

So it's leaking on the gland where the rod slides thru? Unusual to use an o ring in that application but I have seen it before. A quad ring they call it would work much better, they have an x cross section that acts sorta like a cup seal under pressure. One other thing to check is that the groove isn't worn, or that it wasn't remachined bigger to remove wear or pitting in a previous rebuild and now the factory o ring is too small

George talk to Baum iron seal experts Omaha neb

If the end is leaking externally and the end is held in by a round wire snap ring.And if the end is leaking by the snap ring and not by the shaft Like on a 148 JohnDeere loader I have on my 3rd time used 3 wraps of Teflon tape under the o ring Pulled tight and it hasn't leaked in 2 years I also used gun grease for lube when i put it back together. I put the tape in the groove before I put the o ring on. I think the cylinder tube stretched in diameter at the end.

Has it occurred that the leak may not be from where the O-ring contacts the piston? Maybe it is leaking around the backside of the O-ring. Look carefully at where the leak is actually coming from.

Goerge, a piece of the thin round weedwacker line works good on the piston seals to pull it around d the piston. Just loop it through the seal and get a good grip on the ends of the line and pull to help work it around the piston.

Go to Surplus Center website and match one up,worn out cylinders are a constant source of aggravation. Hydraulic Cylinder bores wear out just like cylinder walls in an engine.

I'll try that next time. Wasn't hard to get on, just twisted 90.

I agree. There's some darned tough cylinder seals available nowadays and the folks at Baum are good to work with.

You will find that the shop is correct about using epoxy goop on the bore or rod. If it works at all it wont be for long. Next time you install piston seals warm them in boiling water and they go right on and shrink back after cooling so they work correctly.
"hydraulic" shops vary considerably in knowledge and abilities. The one I use would retube that cylinder and install a new rod. Believe me I understand being thrifty but sometimes a person has to pay to play, LOL

M w J,
I'm going to try the Teflon trick. I thinking it will work. Not going to repeat doing the same thing 6 times and getting the same result, leaks. Sometimes leaks show up later, so I'll Post back later with results. I have some blue Teflon that is thicker and stronger. Going to use it.

Time to get to work, put it back together before the barn warms up.
geo