Chevrolet Repair: truck wont start, fuel gauge, electric switch

Question
I have a 1987 Chevy Scottsdale 4x4.  It has run great for the two years that I have owned it.  After work I added a quart of oil as I have every few months.  I tried to crank the engine to no avail.  It cranks but won't start at all.  I can't figure out what's going on.  This truck does have a dual tank with an electric switch.  It will only work when the switch is switched to the left side.  I have tried switching it back and forth, still nothing.  Can you suggest a starting point to begin looking.  

Answer
I think that the switch has gone completly out and your not getting fuel to the engine. 1987 was the last year before they went to TBI if my memory serves me right. If your switch is working then the fuel gauge will register for the side it works on, when you switching it back and forth see of there is any change of the guage, if not then I would say your switch went bad. If there is movement then maybe your fuel pump went out. Easiest way to check that is disconnect inlet fuel line from carb and turn engine over for one or two seconds, see if fuel is coming out of pump. If not disconnect fuel line too pump and see if fuel comes out there, if so then pump is bad, if not then switch is bad.