LD1
Epic Contributor
I will add that it's unlikely your issue, if it was you wouldn't be able to curl
Pop in FEL Curl Cylinder in my BX25D - Bucket uncurls on own weight
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I tried to pull the rod with just my hands and no leverage and it wouldn't budge. But I wasn't trying very hard, I will try again later today after work. Hydraulic lines are off, obviously, but I didn't, and wasn't planning to, pull the connectors off the assembly. I'm assuming they don't have valves in them, or am I wrong? Obviously I have never tried to disassemble hydraulics before so any advice is appreciated and I am sure will help others if/when they get into my predicament.
LD1
Epic Contributor
No valves. Lines off should be fine
I went home for lunch and was able to pull the rod without much effort. I swear I tried on Sunday but maybe not. Anyway, it does extend all the way as if I were running it on the tractor and does not come out. When I take it apart, I'm going to take some pictures for you all to see, after all, who doesn't like looking at the guts of machinery, right?
LD1
Epic Contributor
That means Piston still attached to rod. Might have blown seals out. There are ways to test, but require hooking cylinder hoses back up.
Hook hoses back up, extend cylinder all the way (like dumping the bucket), the unhook the rod side hose and put in a bucket. Then try extending again.
Extending pumps oil in the base end hose, and puts pressure on the Piston to extend the rod. With the rod all the way extended, it won't extend any further but it will build up max system pressure. There should be no oil coming out the rod side hose.
If you blew the Piston seals, oil will flow around the Piston and come out that hose. Anything from a trickle to a geyser. That will for sure tell weather seals are blown
Hook hoses back up, extend cylinder all the way (like dumping the bucket), the unhook the rod side hose and put in a bucket. Then try extending again.
Extending pumps oil in the base end hose, and puts pressure on the Piston to extend the rod. With the rod all the way extended, it won't extend any further but it will build up max system pressure. There should be no oil coming out the rod side hose.
If you blew the Piston seals, oil will flow around the Piston and come out that hose. Anything from a trickle to a geyser. That will for sure tell weather seals are blown
LD1
Epic Contributor
Not talking about an external visable leak.
Rather oil blowing by the Piston seals inside the cylinder. That oil will come out where the hose is attached at the rod end. With the hose connected, that oil that is bypassing just goes back through the valve and into the tractor.
Need to fully extend then take hose off to see how fast/much oil is bypassing. Like I said, with hose on it just goes back to tractor
Rather oil blowing by the Piston seals inside the cylinder. That oil will come out where the hose is attached at the rod end. With the hose connected, that oil that is bypassing just goes back through the valve and into the tractor.
Need to fully extend then take hose off to see how fast/much oil is bypassing. Like I said, with hose on it just goes back to tractor
I think I understand. I don't know if this tells you anything but when I disconnected, the rod was fully pushed in, oil came out of both ends. I need to teach myself how to read the hydraulic schematic. I'm sure it's not hard but I think it would help me understand what's going on.
LD1
Epic Contributor
There is two cavities inside the cylinder. The rod side of the piston, and the cap side (base end).
the two hoses go one to each of these cavities.
As oil is pumped in the base end, it pushes on the piston and the rod extends. When this happens, the oil that "was" on the rod end is pushed out. So oil goes in base end, and comes back out rod end.
The opposite happens when retracting. Oil goes in rod end and pushes on the piston to retract. Oil that is presently on the base end is pushed back out the base port.
The piston has seals around it that seal tightly to the cylinder bore. Keeps oil on their respective sides of the cylinder and in their own cavity.
When you extend the cylinder all the way, and fill that cavity....it pushes all the oil out the rod side. At this point the cylinder cannot extend any further physically because the piston is contained by the gland cap (what you need the special tool to remove). From here.....if you continue to try to extend the cylinder, the oil is contained by the piston seals and does nothing more than build pressure up to whatever your tractor is set at.
IF the piston seals are leaky.....it wont build full pressure, rather it will sneak by the piston VIA the leaky seals.....and out the rod end port and back through the valve. The SAME path the oil takes from that rod side when extending to expel the oil.
So if you extend the cylinder all the way, then remove the hose on the rod side of the cylinder and then try to continue to extend....obviously the cylinder cannot physically extend any further. BUT....if the seals leak, the oil will start coming out that rod end port. If seals are good, you should be able to hold the lever to extend several seconds and not get more than a drop of oil out that port.
Clear as mud?
the two hoses go one to each of these cavities.
As oil is pumped in the base end, it pushes on the piston and the rod extends. When this happens, the oil that "was" on the rod end is pushed out. So oil goes in base end, and comes back out rod end.
The opposite happens when retracting. Oil goes in rod end and pushes on the piston to retract. Oil that is presently on the base end is pushed back out the base port.
The piston has seals around it that seal tightly to the cylinder bore. Keeps oil on their respective sides of the cylinder and in their own cavity.
When you extend the cylinder all the way, and fill that cavity....it pushes all the oil out the rod side. At this point the cylinder cannot extend any further physically because the piston is contained by the gland cap (what you need the special tool to remove). From here.....if you continue to try to extend the cylinder, the oil is contained by the piston seals and does nothing more than build pressure up to whatever your tractor is set at.
IF the piston seals are leaky.....it wont build full pressure, rather it will sneak by the piston VIA the leaky seals.....and out the rod end port and back through the valve. The SAME path the oil takes from that rod side when extending to expel the oil.
So if you extend the cylinder all the way, then remove the hose on the rod side of the cylinder and then try to continue to extend....obviously the cylinder cannot physically extend any further. BUT....if the seals leak, the oil will start coming out that rod end port. If seals are good, you should be able to hold the lever to extend several seconds and not get more than a drop of oil out that port.
Clear as mud?
Yes, that is clear. Thank you. And that's how I assumed they worked. The way you said it before made it sound like there was a bypass built in. Anyway, what you said in the last post makes perfect sense.
Based on the operation of the bucket cylinder fully extended or retracted, and the fact that it won't hold the curl/uncurl by itself, and that it "popped" a couple of times where the sound was coming most certainly from the cylinder, I think that pretty much proves there is a leak in my mind. I almost liken the sound to if you have one of those rubber poppers that you flip, set on the ground and then they flip back and bounce off the ground. It almost sounded like that. I could do your test and mess with the fluid, or I could just open it up and inspect it.
Which begs another question, let's say I was totally wrong and the problem wasn't in the cylinder at all. Is just the act of opening the cylinder and taking the rod out require that all the seals be replaced or can the old ones remain? And, what if it just that one of the seals rolled off (however it may do that, I don't know). Does that seal or all the seals need to be replaced, or can it just be reset?
Thanks again for all your answers, I really appreciate the advice!
Based on the operation of the bucket cylinder fully extended or retracted, and the fact that it won't hold the curl/uncurl by itself, and that it "popped" a couple of times where the sound was coming most certainly from the cylinder, I think that pretty much proves there is a leak in my mind. I almost liken the sound to if you have one of those rubber poppers that you flip, set on the ground and then they flip back and bounce off the ground. It almost sounded like that. I could do your test and mess with the fluid, or I could just open it up and inspect it.
Which begs another question, let's say I was totally wrong and the problem wasn't in the cylinder at all. Is just the act of opening the cylinder and taking the rod out require that all the seals be replaced or can the old ones remain? And, what if it just that one of the seals rolled off (however it may do that, I don't know). Does that seal or all the seals need to be replaced, or can it just be reset?
Thanks again for all your answers, I really appreciate the advice!
