From bad to worse

[corvette8n]

https://www.fordbarn.com/forum/showthread.php?t=296663

So after I did the compression test, I decided to back the car out into the driveway to hook up my vacuum gauge. No start, tried some starting fluid down the carb no dice, plugged the timing light into one of the wires, no spark. I measured the power at the top of the coil, 6 volts, that doesn’t seem right. So I guess the dizzy needs to come off, how do I check the resister under the dash.?

[rich b]

I don't think a reading of 6 volts across the resistor under no load is necessarily bad; maybe I'm wrong about the first part; but you do need to figure out why there is no spark when you do have juice to the coil.

[corvette8n]

So what’s the best way to test this style coil, Skip rebuilt mine about 3 yrs ago but I have no spark.

[Andy]

You can check low voltage resistance from the terminal on top to the spring contact on the bottom. It should be low ohms. Like 2-3. The high voltage windings are high ohms. It should be 10000 ohms or so.

[alanwoodieman]

pull the rotor button off the shaft and look for carbon tracks on the shaft--could be shorted out!

[aussie merc]

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shorted rotor is more common than you think specially now nos stock is getting harder to get ive actualy seen where they have put heat shrink under the rotor to help stop this

[Jack E/NJ]

>>>So what’s the best way to test this style coil,>>>


Make a spark. 8^) Put a plug in an old 440 boot. Tape 440 center wire to coil's high-tension brush. Hot wire coil. Ground plug. Momentarily pigtail coil's point contact to ground. Look for a plug spark. Jack E/NJ

[aussie merc]

testing resistor can be done at the coil connection test light at the wire to earth turn on should be bright but will start to loose some of it brightness around 30 seconds as the resistor takes effect should stabilize around 4.5 volts [need the test lamp as modern multimeters dont draw enough current to effect the resistor]

[deuce lover]

Originally Posted by corvette8n

So what’s the best way to test this style coil, Skip rebuilt mine about 3 yrs ago but I have no spark.

If you have a multimeter you can clip it to the terminal on top and the other to the terminal that the condenser attaches. If it buzzes the circuit is closed so you should at least have spark.That test doesn't mean that the coil is completely good.When coils get hot the circuit can break also.Now the condenser is another story.I would replace it or try another.

[marko39]

Originally Posted by corvette8n

https://www.fordbarn.com/forum/showthread.php?t=296663

So after I did the compression test, I decided to back the car out into the driveway to hook up my vacuum gauge. No start, tried some starting fluid down the carb no dice, plugged the timing light into one of the wires, no spark. I measured the power at the top of the coil, 6 volts, that doesn’t seem right. So I guess the dizzy needs to come off, how do I check the resister under the dash.?

To test resistor the points must be closed. With ignition on you should have 6 volts entering resistor and 3-4 volts leaving which is what you should see at coil. If you have 6 volts at coil car should start although it would be wise not to run it very long.

[Frank Miller]

Not completely familiar with this coil but there is a wire that goes to the points. If you connect a test light to that and crank the engine with the key on the light should turn on and off. If it stays on you have a bad connection at the points and they will need to be cleaned.