So I've been reading a bunch of posts for simular swing problems, but I haven't found one thats exactly the same. I am new to trouble shooting backhoe's But I work around hydrolics. My backhoe's has lost it's swing, when I try to use the swing, no other function works either, I thought there was a issue in the valve, sending all the fluid straght back to tank. I pulled the spool and all the orings seems to be in tact. I then pulled the upper and lower (i'm calling them) pressure relief valves. Both where missing an oring. I thaught I found my issue, so bought new o rings for the spool and both valves (inclueding the inner needle oring). I did not change the orings that go on the item that screws in from the back (maybe called poppet). I did not regain my swing. Mine has peddles and they are low to the floor, but I have got ahold of the linkage with an adjustable and I am sure that I have shifted the valve all the way with out getting swing. Mine hase 2 cylinders, it's an 1988ish. If its level a not on the ground, i can get out and push it all the way right and left. I am now thinking it may be leaking past the piston inside a cylinder, Unless some one points me in another direction, tomorrow I will pull the lines off and cap them and check pressure going to them. Any ideas will be appriciated. Thank You
If you can move it sure appears it's a bad piston. If you cap the line and give the foot pedal a quick push you'll know in a hurry if there's pressure the hose will jump.
Thank You Billrog, There is 1 other symtom, When I first start trying to use it, it seems to work. It goes to the left and if I let the bucket drag the ground, I can hear the it build pressure and drag the motor down a little. Going right is alot weeker and after a few swings both ways, it moves less and less, gets weeker and weeker. untill its limp. I still think it could be a piston seal. It is sitting in the middle of a snow covered field about an hour north of me. If it is not the piston and I find that it indeed is not getting pressure to the cylinders, then what. Back to the valve I guess. Do you or anyone have a backup idea. I did not take the anti cavitation poppets out of the valve, they are hard to get to and just the name leads me to think they are not important. I have been wrong alot in my life.
Mitch wish I could be of more help my philosophy is start simple I can't see how 2 valves would give up at the same time so it should at least swing one way I'd think ? Best of luck not envying you .
It is very unlikely, but it if you can swing the boom side to side by hand that would almost mean both cylinder pistons have come off the rods. I would be looking at them and putting new seal kits in them. You should do what needs to be done to get the foot pedal linkage tightened up. It is the only way you will get the spools in the valves to get full travel.
One of my pistons was unscrewed, I'll be back in business in no time, thank you for your help.
Mitch happy your back in business it's a good feeling to have. My thought at one time was the same as Tinker how could 1 piston have that effect until my neighbors skid steer had 1 piston go & acted in the same manner as your swing. In a lot cases all anyone can do remotely is give encouragement. There are times when different components can create the same symptoms.
I agree, I appriciate Tinkers imput, He may have raised a question in my mind, but I have the advantage of hind sight. I took the wrong cylender off, home, and apart 1st, only to find it was in good shape. me thinking I understood something kept me from spending 10 minutes to pull the second cylinder off to bring home on the 1st trip. It cost me 2 hours in drive time. I didn't read his post until I was done. I am going to replace the seals in both, one had a rod seal weaping and I can't remember which one. They are off now and the cushion pin got bent, so I will freshen them both up, ordering parts anyways. Adjusting my linkage wouldn't be a bad idea either. Thank You Both
If some Bozo didn't get one cylinder rod nut (or) bolt tight enough there is a fair chance the other side needs attention. It is much easier to unscrew the gland, with those cylinders on the machine . I never remove swing cylinders to reseal them.