I have a Johndeere Ct 322 with parking brake issues. There has been extensive work done to the machine in the last year, the hydraulic pump has been replaced, both final drives, boom and bucket solenoids and parking brake switch/valve body. The machine starts and runs fine but the brake will not release unless you raise the boom and tip the bucket back and forth a couple times and while operating if you lower the boom the brakes will apply. Any suggestions will be helpful. Thank you
Welcome to HEF Mike! You will need to check the charge pressure on your machine (tee into the hose that goes from the filter to the side of the hydrostatic pump). Spec is 250-300 psi at fast idle. You will need to have a long hose so you can sit in the cab and check the charge pressure with the park brake on, then check with the park brake off. Check the pressures at both idle and full throttle and post the results. If it is low you would normally need to flow test the charge pump, but since you mentioned a park brake valve body (as well as other parts) I need to ask, did you mean the filter head? The relief valve for the charge system is in the filter head and is none serviceable. Also did this problem only start to occur after the repairs?
I replaced the park brake switch/ valvebody(at least that's what johndeere called it) it is located down by the foot pedals 5 or 6 hoses connected to it and it has a small solenoid on the top side. I have a couple hundred hrs on the machine since the repairs have been made. Thanks you for help, I will see what I can do