Originally Posted by UtahYork
2. Power to my ignition switch comes from the starter post wire, but I'm not sure if I used a #10 wire. More likely I used a #12 and I can change that. I have a 30A fuse on this line and it was the one blowing when I'm trying to start the engine.

#10 wire is good for 50 amps at 10 feet of length, 100 amps at 5 feet
#12 is 35 amps at 10 feet, 60 amps at 5 feet.

30 amp fuse is too light for the alternator output that happens immediately after starting. Needs to be closer to rated output of the alternator.

Quote
3. I picked up a ground wire for the alternator and I'll get that installed

GM didn't run a separate ground wire to a 10-SI alternator.


'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.