Hi: This is a new switch. I have even tested (OK) the start solenoid, and tried another from an operational (Husqvarna) tractor. Yes; the red (letter B) on the switch is 12V feeding the switch. The White (S) is to the Start solenoid (Power) terminal. Both "main" grounds are fine. When I run 12 V direct from the battery to this white (solenoid) terminal the solenoid activates and powers the starter. When the ign. switch is turned to Start (S) there is 8.46 V there and the white solenoid conductor has 11.46 V (?). The battery reads 12.70 volts. I have an operational Husqvarna in the shop and I tried this Ignition Switch and it too tested 8.5 V at the "S" terminal. Both ignition switches work fine on the Husqvarna and test at 12.68 Volts. Both Solenoids work too!
Thank you: I am at a loss with this thing. I have been unable to find a correct Murray Electrical schematic and the one from the parts manual is pretty useless. I have been a licensed Canadian Mechanic for many decades and am embarrassed by this! I'm "retired" here in Mexico; I mostly do PWC's, outboards (Yamaha) and light construction equipment; there aren't many tractors sold here.
