# 1966 Ford 3000 won't fire



## wahawkins (Apr 7, 2015)

1966 Ford 3000 won't fire a lick. Rebuild starter and turns engine over great. Points seem to be clean and gapped correctly. New spark plugs. Voltage between two bolts on coil is 8v. Voltage between coil and battery is 12v. While turning engine over, voltage between the two bolts on coil drops to 4 or 5 volts. There is a third wire on coil that's goes up over the engine which is burnt in to. I assume it is a sending wire and shouldn't have anything to do with allowing the engine to fire. I may be wrong on that assumption. Any suggestions? Thanks


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## HarveyW (Sep 15, 2014)

Hello wahawkins,

That burned out wire you see is a resistance wire. You have to replace it. That is a 6 volt coil and you need the resistor wire for the tractor to run. 

During cranking, there is a wire from the starter solenoid that temporarily provides 12 volts to the coil (drops down to +/-8V during cranking). This provides a hotter spark during cranking.

This is a very good system IMO, but I'm sure others will badmouth it. 

To monitor for spark I usually pull a plug and put it against ground with the plug wire attached. Crank the engine and you should see a blue-white spark across the plug gap.

Ultradog often posts a picture of a HOT spark. Can't find it right now..

As a temporary measure to see if the engine will start & run, run a wire from battery hot to the coil input terminal. You don't want to run the engine for an extended period with this arrangement, as it will burn the points.


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