no spark

These step by step "isolating roadside problems in 10 mins" procedure or hotwiring as per these attachments have helped me many times
 

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All good above. Bypass your switch and heavy cable. If switch is pop out unhook the heavy cable from the distributor.

With the modern distributor upper plate installed you can run a jumper from the + post of the coil, (the wire that goes to the switch) directly to the distributor. Unhook the red wire to the switch of course. If you have a ready-made switch bypass cable, use that.
 
This post really scares me. I am hoping that me fresh battery will solve my problems, otherwise I am dead.
 
Battery voltage on both sides of the coil, battery voltage at the points says the power is going through the switch, through the cable, through the notorious pigtail wire up to the points. A weak spark ( like a dim light bulb or slow starter) could possibly be a bad ground. Tom Wesenberg carried jumper wires with alligator clips. Attaching a jumper wire to the problematic item like the distributor, light bulb to a know good ground or back to the battery will show if it’s a bad grounding issue ! Yes you can have battery voltage at an item but because of corrosion, bad connections, broken wires the voltage will not carry a load , like a coil or light bulbs. Sometimes using a test light will find issues quicker than using a VOM. I’am thinking that paint on the head is insulating electrical the distributor ??!!
 
If you have bad connections to the primary winding, you may not have sufficient current to saturate the coil. Try the hand crank to start the car. This leaves out the heavy draw of the battery.
 
Ord, there is a boss on the cylinder head around the distributor hole. Clean the paint off there too.


Before removing your distributor, take and ohm reading from the point arm to a clean head nut. I've only done this once on our coupe, and it was a small reading to the right of the decimal. A small fraction of an ohm. With heavy paint you may get a high reading. The amp reading suggested above would also be revealing. (turn the ig switch off to use the ohmmeter)
 
If you use a voltmeter referencing the battery ground post, you can easily find a resistive connection or resistive points etc. Use the above wiring diagram, just remember: At the coil, battery voltage on both terminals with points open. Point side needs to be at 0V when points closed. If not, trace it back to see where you have the bad connection/resistive. This is measured with the RED voltmeter lead on the BATTERY GND POST.
 
update, cleaned paint off the boss on the head where dist goes, had a weak spark at points still and no spark from coil. rechecked clearences and found rotor to cap about .060. Replaced rotor and reduced gap but still no spark. Replaced the coil wire from from my driver model a and had spark. Hit carb with either and engine fired right up and ran for a couple of seconds. Found ignition switch defective but not always. new switch coming. Coil wire came from a ford V8 and I guess that the wire was the modern style and Henry didn't like it. New wire also coming. I am not there yet but getting there. I had to stop for the day to go teach a class so hopefully it should be resoved in the next 2 days.
 
Sounds like you have things going in the right direction! Thanks for letting us know what you found!
 
Installed new coil wire and no change. Feeling pretty frustrated and left it alone for a few days. There were 3 of us trying to get the problem sorted out. Went out today turned on the switch and had a better spark from the coil. Engine fired right up. adjusted idle and mixture ran carb dry( forgot to turn gas on). Turned gas on on and engine fires right up every time. No idea what changed. My friend stated he said a prayer to the lord last night about the engine.

All I know it runs fine now and maybe a little more potent than I expected,.080 over, over size valves, 5.5 comp and a touring cam. It sure sounds healthy!
 
Now I lay me down to sleep.
I pray the Lord my Ford to keep.
If it should roll before I wake,
I pray the Lord to put on the brake.
 
Been starting and running fine everyday. Can't wait until I get a body to put on it. It drives great but due to no body very limited road use.
 
These step by step "isolating roadside problems in 10 mins" procedure or hotwiring as per these attachments have helped me many times

You isolation wiring is a great idea, however, how do I handle the high tension wire from the coil to the distributer cap? There is a second wire that comes along with the high tension wire that is screwed into the top plate of the distributer. What do I do with that? Leave it off?
 
Frank, you say another wire follows the high tension lead from the coil to the upper plate??? I don't believe there is such a wire on a stock Model A setup.

If one end is screwed to the upper plate, that is a ground. Where is the other end attached?

Pics of your battery and its connections, your junction box etc. would help.
 
Frank, you say another wire follows the high tension lead from the coil to the upper plate??? I don't believe there is such a wire on a stock Model A setup.

If one end is screwed to the upper plate, that is a ground. Where is the other end attached?

Pics of your battery and its connections, your junction box etc. would help.

I have a model b engine 1933
 
Her is a wiring diagram of my engines electrical system
 

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In the diagram, the item called "circuit breaker" (red Arrow) is the ignition points. Both it and the condenser are inside the distributor.
HTH.
 
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