what other valve operating mechanisms are there on engines, and how do they work?

Answer 1

You mean besides the valves in the heads used for combustion control?

ok... here we go lets just do a car in general..since most of this stuff is attached to or a part of the engine

1) Fuel pump. valves keep the fuel going in one direction

2) Smog pumps.. same thing.. \

3) Oil pump... if the oil doesnt circulate the engine will not run for long..

4) Air conditioning (two)
a) The compressor fluid.. it MUST go in one direction or it can not be compressed...
b) The air flow... many cars have flapper valves to keep the air going into the car and not out under the engine. Same for the venting system... the fresh air vent is just a manual valve.
5) Brakes: no valve..no pressure.. no pressure, no stop. No stop, .. well then you won't have to worry about any more valves.
6) Tires... after all they call them VALVES on the tire stems..
7) Power steering pumps.. same story ... different pump
8) Gas tank... this is getting pretty lame, but that little flapper just inside the gas nozzle opening.. it closes when you pull out the gas nozzle... well technically it too is a valve.
9) Water pump... some do some dont... for those that do see #7
10) Lube 'zerts' (the little nozzles where the mechanic greases your car. .. ... simple valves to let the grease IN and keep it there.

is that enough....?

Answer 2

you have your intake and exhaust valves that are controlled by your engine,you have an egr valve that is controlled by vaccuum and some vehicles have a control valve for heat &a/c.also you have proportioning valves located in your braking system which are controlled hydraulically by pushing your brakes