Getting tired of hydraulics- Another help needed thread

[futuresweets10]

When I pull the spool up is when it does not work right, when I push it in thats the function that does work. Which secondary (the one on the top or the one on the bottom) would the problem be in?

I got the one on the bottom off and took it apart and everything looks good. The one on the top is not coming out with out taking the entire valve assembly off. Removal and re-installation is about a full day worth of work, so Im not looking forward to that.

 

[futuresweets10]

Well I just got the top secondary out and everything looks good in it.... I am at a complete loss as to what it could be. The shop that re-did the valves didnt find anything in the valves that could be a problem and now after checking the secondaries that pretty much eliminates the valves I would think. I dont think it could be the cylinder because it holds pressure on one side.... With that logic there is no problem, yet the bucket still doesnt hold. Im seriously about ready sell the **** thing for scrap.

Here is the only logic that makes any sense to me now.... Neither the valves nor the cylinder should be the problem with basic laws of physics, but one has to be. When the hoe was parked for a year before I got it the FEL arm was up and I assume the bucket was up or level for this time. It worked fine before it was parked and now it does not. I dont see a valve problem happening while the unit is parked, especially since I paid almost 300 for a hydraulic shop to go through the valves and then I took both secondaries off and checked them. If a cylinder was up, with weight on it, for a year or so, could that eventually cause the seal to blow from having to hold the weight for all that time?

 

[J_J]

Have you tried a gate valve in the work port to see if it will hold. If it will hold, then it is the valve, worn spool, or work port relief valve leaking, maybe some debris causing the relief not to seat.

 

[futuresweets10]

Have you tried a gate valve in the work port to see if it will hold. If it will hold, then it is the valve, worn spool, or work port relief valve leaking, maybe some debris causing the relief not to seat.

No, how exactly would I go about doing that....

Like I said before, I had the valves re-done at a shop and the problem was there before and after the rebuild.... I also pulled the work port valves out and there was no debris in them or down the the valve assembly where the work port valves came out. The shop said the spools looked good.

 

[kenstrac]

I had a similar problem on a BH piston the bolt that holds the piston to the rod was loose .
Pressure against piston would seal the piston putting pressure towards the rod,applying pressure on the rod end would push the piston away from the rod and it would leak between piston and rod.

 

[futuresweets10]

I had a similar problem on a BH piston the bolt that holds the piston to the rod was loose .
Pressure against piston would seal the piston putting pressure towards the rod,applying pressure on the rod end would push the piston away from the rod and it would leak between piston and rod.

I doubt thats my problem being as it sounds like is possible and nothing possible could ever happen.... As soon as I find the tool to take the gland off I will take the cylinder apart and see whats up with it....

 

[dcyrilc]

I doubt thats my problem being as it sounds like is possible and nothing possible could ever happen.... As soon as I find the tool to take the gland off I will take the cylinder apart and see whats up with it....

My question is have you tried reversing any of the hoses yet to see if the problem moves or stays. This will isolate the problem to either the valve or the cylinder. If the problem moves, it's a valve issue - if it stays the same, it's a cylinder issue.

 

[futuresweets10]

My question is have you tried reversing any of the hoses yet to see if the problem moves or stays. This will isolate the problem to either the valve or the cylinder. If the problem moves, it's a valve issue - if it stays the same, it's a cylinder issue.

Not too many of the lines on the machine are reversible as is.. Would require additional fittings and hoses.... None of that matters at this moment as I just finished taking the cylinder off the machine.... Once I figure out how the **** thing comes apart I will be able to tell if its the cylinder....

 

[J_J]

No, how exactly would I go about doing that....

Like I said before, I had the valves re-done at a shop and the problem was there before and after the rebuild.... I also pulled the work port valves out and there was no debris in them or down the the valve assembly where the work port valves came out. The shop said the spools looked good.

Do you know if the shop pressurized the valve after fixing and did they tell you the results. I believe they are obligated to inform you of the results.

If you add a gate valve to the extend work port, and after you raise the FEL, then shut off the gate valve, and if the FEL remains in place/raised up with engine off, that means that the cyl is probably good, and it is probably a worn valve, or a relief valve leaking.

If the cyl is leaking, with the gate valve closed, I believe the cyl will try and equalize and not fully collapse.

Can you tell if the main relief valve and work port relief valve is working. Did you ever put a pressure gage on the valve?

I would have asked then what the relief valve settings were.

Did you check the torque on the bolts holding the valve together. Maybe to tight.

 

[futuresweets10]

Do you know if the shop pressurized the valve after fixing and did they tell you the results. I believe they are obligated to inform you of the results.

If you add a gate valve to the extend work port, and after you raise the FEL, then shut off the gate valve, and if the FEL remains in place/raised up with engine off, that means that the cyl is probably good, and it is probably a worn valve, or a relief valve leaking.

If the cyl is leaking, with the gate valve closed, I believe the cyl will try and equalize and not fully collapse.

Can you tell if the main relief valve and work port relief valve is working. Did you ever put a pressure gage on the valve?

I would have asked then what the relief valve settings were.

Did you check the torque on the bolts holding the valve together. Maybe to tight.

Pretty much everything you listed is a NO. I still dont quite get the gate valve thing as the work port valves arent "inline" with anything. Never put a pressure gauge on the valve as I would have no clue where to put it. They didnt give me ANY testing info or specs on the valves though. I doubt it has anything to do with the bolts being to tight as the problem was there before they worked on it.

Being that I already have the cylinder most of the way off I think I am going to go through it and see if there is a problem there.... If the cylinder is fine then I know for a fact is the valve and I know the 300 that I paid to have the valve re-done is wasted.... If it is the valve I am going to shoot for making the company that did it come to my place (with out charging mileage) and fix it right this time on their dime