Disappearing Spark update - nope, not fixed yet : (

[SDJason]

Originally Posted by Phil

If you haven't I would change the condenser. The are cheap and can cause wired problems. If I understand correctly when you are cranking the engine you are going coil wire to head bolt.
If you can, I would borrow a known good distributor see if that solves the problem then work backwards from there if that clears the problem.

If that does not do it Try to borrow a coil are try that.

I am assuming the car was running and just developed this problem.

I have thought about buying a second distributor, just to have on hand anyways - but am hoping I can figure out this puzzle first.

Replacing both the condenser & coil with new ones still ends with the same symptom - good spark when manually opening the points, but the spark disappears when using the starter.

Long story short (no pun intended) - almost a month ago now, I was left by the side of the road. The initial symptom was a short somewhere in the distributor (no voltage on the points arm). Somehow, that disappeared during the course of dismantling & putting the distributor back together a few times while trying to trace the short. Now I've got the disappearing spark while using the starter. I thought once the short was gone, that'd be the end of it, but no such luck. I've gone over pretty much the entire electrical path, and everything seems fine.

If I could use a handcrank, I'd try that - but the engine is off by about a 1/4" to the right. Next up, I have to find a friend or neighbor to bribe to help me push the thing down the street and try popping the clutch. I suppose it's also possible the battery is weak, but the engine seems to be turning with the starter as fast as I think I remember it doing before, and the cells come back at about 75% with a hydrometer...

This thing really has me puzzled (and frustrated)...

[Tom Wesenberg]

"I really need to get a neighbor or friend to help me try to push start the thing next; I may have to offer up a bribe to find a willing volunteer... "

That would be my next step. In fact since what you have sounds exactly like what happened to me a couple years ago, I hope you don't do anything else but push start it, then see if it doesn't work fine after running a few minutes. That's all it took for me, except I was able to hand crank mine, so it didn't need a push start. Is there a nearby hill you could roll down?

[Mike V. Florida]

Originally Posted by Phil

Ok, question. You say opening points manually gives you a spark every time. Does that mean a spark at the points or are you checking the spark through the coil wire to to a head bolt? The later would be the test you would need to make to make sure you have a good coil.

If he does have a large spark just at the points, it would point to a bad condenser as the condenser reduces the spark at the points and supplies the coil for an extra boost.

[Tom Wesenberg]

Jason did mention that the spark from the end of the coil wire is fine when the points are opened by hand, but not so fine when the starter is cranking the engine. This is identical to what I had a couple years ago. I tried sanding the points a few times, but it was always the same thing. Finally I figured I'd just hand crank it, and it fired right off on the first pull. When I first got my 1939 motorbike running I had the same points problem. I'd have some spark, and then when I went to drive the bike it quit. I'd have to remove the cover and flywheel, sand the points and try again. Finally after about a dozen times of removing the flywheel and sanding the points it kept running like it should. Some times points can be finicky and for no apparent reason. When I worked at the GM dealership, I'd get new points out of a foil sealed box and about 1 in 10 wouldn't work.

This is why I hope Jason push starts the car, to see if the same fix doesn't work for him as it worked for me.

[Popeye31]

Ok I think the problem is in the points plate or the connection from the bottom plate to the points post. the way to check this is first put a piece of paper between the points contact so the point aren't closed. next take a multi meter and check for 6 volts with the key on at the point post that goes through the top plate . put your red lead on a head bolt and the black lead on the points post.if you have 6 volts change the points. if you don't have 6 volts take the distributor cam out. place a rag on the side of the distributor and place the upper plate on the rag so it doesn't ground on the motor. next use the mutimeter and check the wire from the bottom plate to the points post. if you have 6 volts your broblem is the end connector of the wire from the bottom plate is grounding on the distributor base. this is the most common cause of sometime spark on model As. most of the time people replace this connector with a modern style connector that is to big and like I said it grounds out on the distributor body . the fix change the connector to a original style flag type connector . or solder the wire to the post after you put the nut on . you can always desolder it when you need to change points. or swap the original style plates for the modern style plates.

[noboD]

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Disconnect the wire from ignition switch to coil. Power the coil with another battery while cranking. That will tell you if it's distributor or wireing.

[Mikeinnj]

Originally Posted by H. L. Chauvin

Hi SD,

(turning the engine over with the starter results in one or two sparks, then none, but manually opening the points results in spark every time).

The above statement means a "lot".

1. "Definitely" appears your starter is "intermittingly" using up all of your electrical power & not allowing any to get to the points at times during starter rotation.

2. I would do this first as a very simple test:

Place vehicle in 2nd gear, depress clutch, & either push the vehicle by hand by yourself, or have someone else help to push, & when you get up a "little" speed, let go of the clutch with the switch "ON" to see if it will either fire or start.

You can spend the next 6-8 months trying 10,000 other things; but again, I would try the above first & report what happened if I wanted to get it running this weekend.

Results of & reporting "what" happened with this test are most important.

Place vehicle in 2nd gear, depress clutch, & either push the vehicle by hand by yourself........that Ive gotta see !

[Tom Wesenberg]

Originally Posted by Mikeinnj

Place vehicle in 2nd gear, depress clutch, & either push the vehicle by hand by yourself........that Ive gotta see !

That would be tough to do. Someone reported jacking up one rear wheel, placing the tranny in high gear, turn the key on and then grab the tire and turn it to start the engine. Just make sure the car doesn't fall off the jack.

[H. L. Chauvin]

By hand, by yourself, just takes lots of agility, a strong marsh type push pole, & a very strong hurricane force wind in the right direction.

[supergnat]

Check to be sure that your fixed point in the distributor is tight after the locking screw is tightened. I had a problem with my fixed point block which allowed the fixed point to be turn and move around even thought the locking screw was tight. This may be a shot in the dark but it is easy to check. I replaced the fixed point block and the problem was fixed. I identified the problem by using a VOM meter to check the voltage across the points while I hand cranked the engine. The voltage level was very inconsistent.
Supergnat

[Mike in NRN IN]

Is it possible - just wondering since I had a similar problem - that there is short in the ignition switch? I had a replacement switch that failed - replaced it with a 'restored' pop-out switch and my problem went away.

I have also installed the switch cable too far once and it shorted out the lower plate against the distributor body. That was a fun one to figure out.

Good luck.

[1931 flamingo]

If you can't find help to push, park on a hill and let gravity help you get started................
Paul in CT

[Mitch//pa]

Originally Posted by 1931 flamingo

If you can't find help to push, park on a hill and let gravity help you get started................
Paul in CT

The problem is getting it to the hill

[SDJason]

Originally Posted by supergnat

Check to be sure that your fixed point in the distributor is tight after the locking screw is tightened. I had a problem with my fixed point block which allowed the fixed point to be turn and move around even thought the locking screw was tight. This may be a shot in the dark but it is easy to check. I replaced the fixed point block and the problem was fixed. I identified the problem by using a VOM meter to check the voltage across the points while I hand cranked the engine. The voltage level was very inconsistent.
Supergnat

Thanks - I'll check that...

[columbiA]

Back in 56,I had a 32 Chev coupe with a poor battery & no hand crank.If I couldnt park on a hill,I would jack up the LH wheel & with trans in high gear,would give the wheel a flip or two & it would start. As for no spark when using starter,perhaps the starter is drawing to many amps & not enoughvoltage left for ignition.