Suddenly won't start

I concur with Tom you most likely have a poor or partially shorted connection in the distributor lower to upper plate. when you said you had 6 volts after taking out the distributor lead I knew that was probably the case.
Take the cam screw and cam off and rotate the upper plate till it comes out and you will find the pigtail upper to lower plate lead. Check carefully for the lead where it connects to the upper plate and how the terminal is bent. It could be shorting against the housing slightly or have a poor wire connection. I'm more of a fan of using a volt/ohm meter over a test light as long as you know how to use it.

Hopefully you have found it. Remember if you pull the lower plate you need to take the condenser out first. It's common for some to screw the terminal in too far and push the lower plate arm into the distributor housing and shorting... I like to use a piece of rubber inner tube glued on the inside of the housing at that area so it is kind of fool proof.

Hopefully you have found it!
Larry Shepard
Larry
 
I apologize if it appears I am not listening. I read posts 3 and 9 again. I have voltage at the wire entering distributor. Nothing at the points when open. Apparently, the problem is in distributor. I will get help here. Thanks for all of your time.





OK, now we're finally getting somewhere. This is the first we have heard this. I seem to remember that you said there was 6v at the open point arm, but, I guess I'm wrong about that.
Just as Tom mentioned there appears to be a problem between the primary cable and the points.

That connector wire is a very fine multi strand wire that has been known break. Also the ends of that wire have been know to be allowed to ground against something when making the connections.

Fix that problem and make sure you then have 6v at the open point arm, then no volts at the same arm when closed. Then I think the car should start.

And again, get yourself a cheap test light. It'll be one of your best friends. Most test lights will have 12v bulbs, doesn't matter, 6v will still light it.
 
For reply No. 43:

If one researches past Model A Forum suggestions over the past (20) or so years, one can find where usually the typical Model A Cafeteria Style suggestion fixes are offered to try the customary bouncing around and sampling odds and ends, followed by follow up Model A answers after one tries changing the condenser, the points, the coil, the ignition switch, the battery, the battery cables, the light switch, the fuse holder(s), the light bulbs, the ammeter, the high intensity coil wire, the rotor, the generator cut out, the distributor body ..... and even changing the dip stick ....... and then finally .......... one either gives up and sells his Model A ........... or quits bouncing around from pillar to post, obtains and studies a Model A wiring diagram, obtains a multi-meter, and starts monitoring (+) & (-) voltage from point A at the battery to where the failure occurs.

Next, ever notice that the Model A parts suppliers never complain about Cafeteria Style suggested Model A engine diagnostics ...... this is how they stay in business. LOL
 
Yes 6 volts entering distributor. With points open, I do get about 2 volts on the arm, but not 6. If I remove top plate will I mess up the timing? I don't want to add another variable.
 
Yes 6 volts entering distributor. With points open, I do get about 2 volts on the arm, but not 6. If I remove top plate will I mess up the timing? I don't want to add another variable.
Yes, but you need to learn to set the timing anyway. Without a spark, you have no timing. This little scenario you are working on has probably kicked more peoples asses than all other model a problems put together. Learn it now and you will be way ahead of the game.
Take a good careful look around at all the parts of the plate , etc before you take the cam screw loose.Good Luck.
 
Hand crank the engine until the edge of the rotor is lined up exact as this picture. Remove the screw, cam, and top plate. Fix the wire and terminal, them put it back together the same way it came apart. Position the rotor like the picture again, and you are ready to drive. You won't have to recheck timing. If it was TDC to start with, then it will be TDC again.
 

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How did you measure the 6 volts at the distributor? I had a similar problem, but I think I could only measure the voltage at the moveable arm. I discovered the cable that ran from the switch to the distributor was shorting out inside the screw in canister that screws into the distributor. I'll try to post a picture I took after I cut the canister open.
 

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I did as Tom said and removed nut and cam. Top plate not coming out. This has modern points and condenser on top. Hook, I was also thinking that armored cable might be causing a problem inside.
 
I chased the very same problem for a few days. I had the same symptoms. It was the wire inside the armored cable at the distributor. I got a reading of about .5 to .6 volts on the point arm.
 
All fixed. When I took off the top plate, I found that it did not have the pigtail or any wires. Large copper plate underneath and a copper tab on top plate which simply contacts bottom. Obviously a modern type? Anyhow, tab was cocked and was shorting against top plate. Simply bent it so it wouldn't hit. Still pretty close. Probably not the ideal setup but ok for now. I want to thank you all for your patience. It was much appreciated.
 
That wireless top plate is a problem waiting to happen.
Use the original plate and wire if you don't want your car to die at any moment.
 
The wireless modern plate is the older style and was troublesome for the reason you found.


The modern plate of the past 10 years or so use the flexible wire and work fine.

I'm wondering if that wire could be used on the older style modern plate. I haven't looked or tried it, but, I think I would try it. If it will work then it should be cheap, easy and reliable.

I've been running a modern plate for 10 years or so with no problems. I tried it because we have been told they are no good and just wanted to find out for myself. I keep a good original style distributor in the 'spare parts' box in the rumble seat. Last I looked at it it was getting a bit rusty from rattling around back there for so long.

The other issue with a modern plate is the poor quality of readily available points and condenser. The expensive ones from NAPA have been good. I can't think of the part numbers though.

Make sure to use cam lube on the points block and cam. Don't run them dry.
 
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As the others said
I changed out a lot of those wireless plates and put back the original style, as they cause driveability issues and all out break downs...
Fix it right or you'll be on the side of the road somewheres

Glad you found it and hopefully learned something along the way
 
Or have your wife hang on to it while you crank the motor. This only works one time.

this could lead to sleeping on the couch or worse................!
 
Patrick,
Are you saying the current modern wireless plates actually use a wire to make the wireless plate more reliable?? :confused: :eek: :D

I like wire!




Nope, not what I'm saying. Maybe it came across that way, but, its not what I meant. The modern plate I'm using is wired. Bought it like that. I too like wire.

Apparently what I was referring to is confusing. I'm usually confused so that would make sense.

What I was wondering if a wire could be added to the older modern wireless plate. I just thought maybe that would be an easy and reliable fix.
 
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