Problem: leak produced from closed reservoir tank valve.
This is the “boom functions valve” and the arrows show the place where a major leak has developed after powering up the machine when the tank reservoir shut off valve was left closed by accident. Obviously the pic does not show fluid flow. When under power the leak outputs a stream that would fill your coffee cup in about 2 seconds. Make repairs with the valve body in place or remove the assembly for bench work?
Repairs require the valve be removed. 5 individual seal kits are used, part# 352-29006 (see pic below). Note: as suggested by the Altec tech rep, stand the valve on end when disassembling so the ball bearing parts do not fall out and go everywhere.