I have an 04 or 05 Cat 267B track skid. whe the machine is running at idle or full throttle the bucket curls all the way up and you can hear the pressure build up. If you pull back on the joystick and slowly re\otate it to dump the bucket will slowly dump. Cat in idaho said it was the complete joystick assembly that was bad. Anybosy else have this issue and if so was it the stick or something else. Any ideas will be appreciated. Thank you.
Also the bucket curls by itself. The stick is in the neutral position.
If that hydraulic system is controlled electronically could just need to run calibration on it. The electric actuators are controlled by a signal received from controller that receives it's signal from joystick. Could be the joystick position sensor, bad wiring or the controller. Could even be one of the cylinders' seals are coming apart and trash got in control valve hanging up the spool. You rreally need someone in your area to run CAT ET on it to see if there are any codes and to run joystick actuator calibration to make sure it is not that. Now if it does not have electric..meaning it is linkaged...i think all 267B's are though?.....the linkage or cable controlling it are hung. Give me the PIN and i can see how it is setup. Good luck!
Jeremiah, it's a pilot system, so it sounds like something in the pilot system is awry. What exactly... that I'm not sure of.
Ahhh.a pilot system. The PPC valve has little spools inside them. It is the spool just above the number 11 spring in this parts picture. Could be a broke spring on main spool inside control valve or the spool hung still. 80% of the time it winds up being this spool in the PPCV. Tear down the bucket curl spool and that is probally what is going on. Take some needle nose pliers and work that little spool out, sand it up with some emory paper. (or however you spell emery?) You do need some mechanical skill to tackle this one but take your time, relieve pressure in hydraulic tank and give it a try. Good luck!
do the aux hyd cause a problem on the cats? On the bobcats if they are stuck on it messes with everything. Does it do it from start up before you release the safety interlocks or after?
it does it from start up. Before I release the safety.
I took apart the pilot valve and everything saeemed ok. I will sent it to cat to do a diagnostic.
I took apart the pilot valve and everything seemed ok. I will send it to cat to do a diagnostic. it does it from start up. Before I release the safety.
Well I took it to cat and no codes in the computer. They think its the joystick valve. 920.00 dollars. Ouch. I am starting to agree with them, as i have rebuilt the valve body, joystick and main and it is still doing the curl. Any more Ideas will be greatly appreciated. Thanks.
Then it is NOT the pilot control valve/joy stick. Until the interlock is released the joystick has no pilot pressure feeding it. There is a problem with the spool in the main valve. Either it is sticking because of debris or something is broken, possibly a centering spring.
sounds like a valve stuck like everyone has said. on bobcats they use a spool and magnetic coils to run the aux a stem may be bad with debri or just cocked in the bore and allowing oil to flow by. On most machines the lift has a safety hyd lock as not to be able to get oil to the cyliders until it has power going to the coil or valve to release. That way the arms can not lift and kill you as you are entering/ exiting the machine. do your lift arms lift regardless of what you do when you move the funtions and dont come down unless you shut the machine off and use the bypass lower valve? I agree on the pilot pressure not being at the controls until you press the safety release button.