Lack of brakes
It would be wise to check out the Master cylinder, it sounds like it needs a re-seal, I do not know what a W14B is??? but near all loading shovels have 2 line brakes, one for the front axle and one for the rear, fed from 2 master cylinders or 1 tandem cylinder, if its an air over hydraulic system the min air pressure needed would be 65 psi, the usual max working pressure would be 120/125 psi, lots of calipers are fitted with top and bottom bleed screws, this is so 1 caliper does both left and right side wheel station, the only bleed screw you need to be fiddling with is the top/highest one, I always use a water pressure test kit to help me to bleed out a brake system, I fill the fluid pot up, then screw on a test fitting in place of the pot cap, then open a bleed screw a bit and hand pump a few psi into the pot, then do up/undo any other bleed screw/s in the system, I always start on the closest bleed valve to the master cylinder, lots of service manuals say start at the furthest bleed valve, I stick to what works for me and gets the job done, if you use a pressure in the pot system to bleed the brakes, you dont fan the brake peddle and get other people involved in what can be a mucky old job if they pump the peddle at the wrong time, so re-seal your master cylinders and it should work great.
tctractors