I used to love it when a vehicle would come into the shop with half a dozen new parts- - - -and the same symptoms as before the "mechanic's" repairs got started. We called those guys "wheelbarrow mechanics"- - - -roll a wheelbarrow full of new parts up to the job and keep swapping bits and pieces until something fixed the problem- - - -and NEVER take anything off. "It was bad anyway". Sun had a slogan on all their test equipment- - - -"We test- - -not guess!"
Shortly after I started teaching at a state trade school in Tennessee the retired former chief administrator of the tech school brought his truck in for repair. It was a 1955 International pickup with a 6 volt electrical system. The lead instructor had warned me about this one- - - -"It won't start when it's hot, and he won't let me put an 8 volt battery in it!" Sure enough, the vehicle had a new 6 volt battery, coil, rebuilt carburetor, rebuilt generator, voltage regulator, starter, big battery cables, etc., and a BUNCH of ground wires between the frame and the engine. It took me 15 minutes to fix it. While cranking, the starter had 5.3 volts applied to it (excellent)- - - -and the voltage at the coil primary terminal was 4.2 volts! When I reached under the dash and touched the back of the ignition switch, I burned my fingers on the loose, corroded primary wire terminal from the switch to the coil. One lug terminal and about 2 inches cut back to eliminate the charred insulation on that wire, and the problem was solved forever!
Jerry
