valve rebuild.

[bigdeano]

A leaking piston seal should cause a faster leak down when the cylinder is hooked to the valve. The rod area is smaller than the piston area so the pressure will be higher, maybe a lot higher depending on rod to piston diameter. Plus the higher pressure is applied to both valve work ports, not just one like it normally would be. If the valve has some wear it could have noticeably faster leak down.

 

[LD1]

I will admit that a loader lift cyl should be mounted in a push instead of a pull position, but I have seen some old loaders that werent mounted that way. Also there are a lot of other equipment that do mount lift cyl on the retraction side of the cyl instead of the lift. The C frame on a lot of dozers, the boom on a lot of backhoes, some knuckle boom loader, just to name a few. No one is disputing your statements about cyl not retracting unless the oil has someplace to go outside the cyl. You are 100% correct, but I am also 100% correct that a cyl can extend without adding extra oil to take up the space lost as the rod exits the cyl barrel, while oil wont compress, it will expand. Will someone experience it using normal farm equipment with normal loads, with the cyl mounted to push rather than pull, probably not, but lift a backhoe bucket full of dirt with the lift cyl mounted to retract on lift, and let the piston come unscrewed from the rod and see how fast it will fall.

No one is disputing what you say. And what you describe is what alot of members experience on their curl cylinders.

I am not trying to muddy the waters. I am trying to keep it to loaders that have cylinders that push to raise. Because thats what the OP is asking about. And thats what is talked about 99% of the time when false information gets preached like the gospel. Something I, and a few others here on TBN have been trying to correct for a few years now.

 

[ch1ch2]

To test if the piston seals are indeed leaking by causing your issue, you need to try to pick up something you know the loader will not lift. Chained to a stump, something heavy, etc. Make sure you CANNOT lift it. Put the loader up to it and put a little pressure on it. Unhook the loader hoses on the rod ends. Now attempt to lift again. If oil comes out the rod end ports, the piston seals are bypassing. If not....the cylinders aint your problem.

Thanks that is good advise and is no more work because I would have to take the hose off anyway to rebuild the cylinder.

 

[jenkinsph]

You could totally remove the piston seals, and do as you describe, and as long as the hoses and QD's dont pour oil onto the ground, the cylinders aint gonna move and the loader WILL NOT drift.

For a loader to drift, the oil has to go somewhere OUTSIDE the cylinder

My bad, after reading through the discussion following I can see my mistake. The displacement of the cylinder rod prevents it from drifting.

 

[jenkinsph]

I am not trying to muddy the waters. I am trying to keep it to loaders that have cylinders that push to raise. Because thats what the OP is asking about. And thats what is talked about 99% of the time when false information gets preached like the gospel. Something I, and a few others here on TBN have been trying to correct for a few years now.

LD1, you are absolutely right about this and I was wrong and can admit it. Thanks for pointing it out to me.

 

[LD1]

LD1, you are absolutely right about this and I was wrong and can admit it. Thanks for pointing it out to me.

No problem. I am just glad that you understand. As opposed to a thread just last week. I think it went 14 pages going back and forth about this very topic.

 

[ch1ch2]

No problem. I am just glad that you understand. As opposed to a thread just last week. I think it went 14 pages going back and forth about this very topic.

I don't know about others but that thread opened my eyes about my mis-thinking on the cylinder.

 

[LD1]

I don't know about others but that thread opened my eyes about my mis-thinking on the cylinder.

That is all I am trying to do. Educate people. Sometimes it gets out of hand, because people dont like being proven wrong. I dont know where it all started.....the misconception that a cylinder can drift (compress) if the seals are bad. But there are ALOT of people that still believe that. And those people continue to spread the mis-information and its a never ending battle. I'll do the best I can to educate as many people as I can.

 

[muddstopper]

No one is disputing what you say. And what you describe is what alot of members experience on their curl cylinders.

I am not trying to muddy the waters. I am trying to keep it to loaders that have cylinders that push to raise. Because thats what the OP is asking about. And thats what is talked about 99% of the time when false information gets preached like the gospel. Something I, and a few others here on TBN have been trying to correct for a few years now.

I'll agree with that