are you absolutly sure about this model number?
the reach truck is not a FB according to komatsu...
it is an FR and as far as the 14 part?
there is no such thing that i can find

UNLESS this is either an extremely NEW truck which i doubt as thier new truck model numbers are nowhere like this
so......
i can assume this truck is old?
or the dataplate is defaced and you are just reading it incorrectly?

please check it again....

but so i wont come across totally out of line here
in most cases i have dealt with in reach trucks
if you have issues such as this pay close attention to the wiring for the auxillary functions especially where it runs through the mast and terminates at the valve block on the carriage. and yes there is a malfunctioning valve which would explain the symptom of the hydraulic pump deadheading while in operation and the very slow movement of the pentograph cylinders. there are some check valves(some call them counterbalance valves) in the manifold block along with those solenoid valves that could be the problem too.

unfortunatly these issues are hard to diagnose most of the time and its just a process of elimination you have to go through.