When you go from Europe to US, and find the sockets are quite different, you still will
know how to plug stuff in, right? But what if you have never seen an
electric socket before? Chances are, something embarrassing will happen
when you try to use an electric appliance.
The same happens with hydraulic components.
Everybody, involved in hydraulic pump and motor repair, has general
idea about how main components work together, so even when such person
comes across an unknown, let's say, axial piston motor, he will still
know how the main pats combine into a working assembly. But what if you
don't know how a hydraulic motor works? Chances are, something very
expensive may happen if you try to assemble it...
Have you ever thought about what would happen, if
you did something obviously wrong, like, say, mounting the valve plate
the other way round, upside down? Of course, it is impossible for most
pumps and motors due to unilateral fit of the valve plate, but there
are motors, like this Kawasaki M2X170, which allow the valve plate to
be mounted in two manners. Of course only one of them is correct...
Take a close look at the first picture. Yes, that's
right, the valve plate should have been assembled with the brass side
towards the cylinder block. The cylinder block got around 2 mm deeper
before the final stop. And yes, the machine did work for a month (!)
Insane Hydraulics shows you this, so that you don't have to do it at home.