Shaver post pounder
- Thread starter THEPARTYHOUND
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THEPARTYHOUND
Gold Member
No Beez, i wish there was a travel pin of some kind. Ive got a ratchet strap acting as my travel pin! I may have to rig up some kind of travel pin if i get this working though.
I'm not sure I understand the configuration given the description of the flushing behavior. There is a remote valve on the tractor that is connected to the high pressure inlet of the shaver valve. There is a high pressure line from the outlet of the shaver valve connected to the single acting hydraulic cylinder. And there is a large diameter low pressure line coming out of the shaver valve going to the hydraulic fill port on your tractor. There are three positions the shaver valve can be in: neutral, extend the cylinder, and allow the cylinder to retract under the force of the ram. Can you describe what you mean when you say you've "tried to open the valve on the pounder". Do you mean you tried to move the actuator on the shaver valve to the position that should extend the cylinder and nothing happened? Or do you mean the actuator moved but the cylinder did not extend? When the fluid is flowing into the shaver valve and out into the flush bucket, which position is the shaver valve actuator in: extend or retract? I'm trying to understand how fluid can be flowing through the valve if the cylinder isn't retracting, because that's the only place the fluid can come from unless there's a total failure of the shaver valve that's allowing the inlet high pressure fluid to go directly out the low pressure line back to the tank.
I guess here's what I'd do next. I'd disconnect the hose at the cylinder, stick the end of the hose in a 5gal bucket with a towel over the top to keep from getting sprayed, and crack the shaver valve open really quick to see if you get a jet spray of hydraulic fluid out the end of the hose. If you do, assume the valve is working and check the ram. Put a floor jack or bottle jack under the sliding part of the ram and try to lift it. It should go up easily from the lowered position because the springs are just starting to stretch so it's just the weight of the ram you're lifting.
OP
THEPARTYHOUND
Gold Member
That is correct. With the high pressure line from the pounder hooked up to the tractor's remote hydraulics and the pounder valve in the neutral position fluid flows freely out of the discharge hose. I thought this was normal operation for open center hydraulic valves.
OP
THEPARTYHOUND
Gold Member
FWIW, there are no springs on this pounder. It is only gravity and weight that does the pounding.
I will do as you suggest. That makes sense to me...
I will do as you suggest. That makes sense to me...
Yes that's normal operation. Your earlier post made it clear you were flushing in neutral position, I should have read more carefully.
You're lucky you don't have springs. I've had 3 break and they're no fun to change.
Birdhunter1
Veteran Member
What I did was to hold the valve in up mode and let the air/oil mix itself out. Eventually the ram raised, it went alittle bit, then fell slightly, then raised some more, then some more, then no problem at all. I would be willing to bet if this does not work your ram is stuck or you aren't getting oil to it.
OP
THEPARTYHOUND
Gold Member
Ok, i pulled the high pressure line off at the cylinder. When i push the hydraulic valve fluid does come out of the now removed hose, but just a little bit. And if i hold my finger over the hose and push the lever i can hold the pressure back.
OK, next I'd make sure the remote is working. Easiest thing is probably remove fitting from high pressure line going to the shaver valve and do the same test into a bucket with the remote valve open. If you happen to have a stub of hose with a quick disconnect on one end that fits the remote, an easier way would be connect it to the remote valve using the quick disconnect so you don't have to take anything apart.
OP
THEPARTYHOUND
Gold Member
I know that i have fluid coming from the remote because i used it to flush the pounder in the earlier post and it flowed out very quickly...a gallon in only a few seconds.
Then I'd say it's proven that the shaver valve is not working. Does it feel like the valve has complete free motion? Does it seem like the valve handle is moving the same distance when you move it both directions from neutral position? The only thing I can think of before pulling the spool out is removing the bottom cup to see if it's filled with a bunch of rust or some crud that's preventing the spool valve from moving fully into position. That would be an easy check, the bottom cup is easy to take off and doesn't see the hydraulic system so you don't have to worry about damaging anything or losing orings. If it's like mine, there are 4 allen screws that hold the bottom cup on, I've included a photo of mine with my finger pointing at the thing you want to take off. There shouldn't be anything inside that will fall out, but best to put a bowl under it just in case.
OK, hold on, I just read this again. When you say you push on the valve, if it's like mine, that's the direction that would cause the ram to come down, not go up. Did you try moving the valve in both directions to see if either direction produces oil flow?
OP
THEPARTYHOUND
Gold Member
I did try pushing it both directions. When pulling down oil flow through the return hose seemed to increase.
I will post a pic of the part that is missing screws. It seems similar to the cup you were pointing at.
OP
THEPARTYHOUND
Gold Member
*FIXED*
I got the problem figured out. It was operator error. When i plugged the pounder in to the hydraulic port on the tractor and pulled the lever on the tractor to actuate the hydraulic port i got fluid into and back out of the pounder. This led me to believe that i had the lever on the tractor in the correct direction. Today, on a whim, i pushed the lever on the tractor in the other direction. Bingo! The pounder lifted and i was golden! Thanks for all the help guys!
I got the problem figured out. It was operator error. When i plugged the pounder in to the hydraulic port on the tractor and pulled the lever on the tractor to actuate the hydraulic port i got fluid into and back out of the pounder. This led me to believe that i had the lever on the tractor in the correct direction. Today, on a whim, i pushed the lever on the tractor in the other direction. Bingo! The pounder lifted and i was golden! Thanks for all the help guys!
Great, glad it's fixed, but I'm scratching my head trying to understand what was happening. Why would there be any flow to the pounder valve if the remote lever was in the wrong position? There should have been no flow to the valve, because it was connected to the return side of the remote valve, which only sees the return pressure in the hydraulic system. Or was it because the valve inlet was looking at the relatively low pressure in the hydraulic system, and that was enough pressure to force some fluid through the valve and out the shaver return line? I would have thought it would have been more like a dribble rather than a high speed flow.
OP
THEPARTYHOUND
Gold Member
I agree, thats what i thought too. I have very little knowledge of hydraulic systems and that was why i posted up here. It put a gallon of hydraulic fluid through the pounder in a matter of a few seconds, so it certainly wasnt a dribble! Thats why i thought i was on the right port and didnt bother trying to push the lever in the other direction on the tractor.
Tx Jim
New Member
If SCV is operating correctly there should be no hyd pressure to post pounder when tractor scv control lever is moved in opposite direction. Poppet valves in tractor control valve must be leaking internally
