Ignition coil specs

I have a 1952 8N, 12 volt, negative ground. All of a sudden, I am not getting a spark at the plugs. Replaced the condenser twice, filed and reset the points. It looks like all the connections are ok.Still no spark. Next on my list to check is the ignition coil. I replaced it in 2005. The coil has an external resistor.

Does anybody know what the correct resistance should be for the primary and secondary coils? Thanks.
 
Trouble shoot then parts NEVER the other way around

Pull the ignition side wire of the coil. Then turn the ignition on and touch that wire to the coil. You should see a spark when you do that if the points are closed. Then move the engine to a point that the points are open. Then touch that wire back to the coil. This time with the points open you should not get a spark. If you get a spark when the points are open you have a short on the system. Could be where the wires hook to the points or could be the insulator going in the side of the distributor. One way the check if it is the insulator is remove the hook up to the points and try touching that wire back on with the points out of the circuit. If you get a spark then the insulator is likely to be shorted out
 
I don't quite understand what you are saying. Do you mean to pull the secondary wire that goes between the coil and the distributor cap? Also, I would not be able to tell if the points are open or closed unless I have the distributor cap off. Could I disconnect the secondary wire and hold it near the engine block, crank the engine to see if there is a spark?
 
Try again Remove the ignition wire as in the wire going to the ignition switch and then do the spark test. With the ignition on and points closed when you remove and touch it back on you should get a spark each time you hook it back up . With the points open you should not get a spark.

Or you can leave the ignition off and run a hot wire form the non ground side of the battery to the coil and touch it and then remove and you should get a spark that way. Very simple no meter etc needed way to test an ignition and I do it that way all the time.

Just last month I got a Case VAC for $300 and I did that test to ee if the points where good or not. Had no spark so cleaned the points fixed the fuel line and drove it off the trailer
 
Okay, I disconnected the wire from the BAT side of the coil. The wire does not come directly from the ignition switch. It connects to a terminal on the back side of the alternator. See attached picture. The red wire to the right goes to the coil. When I turned the ignition on and touched the wire to the terminal on the coil, I did not get a spark.

I then ran a jumper wire from the positive terminal of the battery and touched it to the same coil terminal. Again, I did not get a spark.

The other day, I checked across the primary terminals, and I did get continuity.

So, does any of this tell me the coil is bad? Thanks.
 
You need to read every thing I write. NO SPARK means the points are bad or dirty. If the points do not conduct power then you will NEVER have a spark when you hook up the coil like I said or out of the coil wire going to the cap. Spark happen when the magnetic field in the coil collapse so every time the points open if they conduct power you get a spark from the coil to the spark plugs
 
Again, I am having trouble understanding what you are saying. I filed the contacts on the points and reset them.

I am trying to check the coil to see if it is good, I think the points are okay. So, I did the two checks you suggested and did not get a spark. Does that tell me anything about the coil?
 
Easy way to test a coil is ground the point side of it and with the ignition side off and ignition turned on hold the center wire that goes to the cap about a 1/4 inch from the block then touch the wire back on and then pull it off. Each time you pull it of if the coil is good you will get a blue/white spark that jumps a 1/4 inch or more
 

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