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I'm having ignition problems too

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Steve_Lawrence

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I cooked my Pertronix unit a while back and put points back in. I checked that there was power to the coil and also that the points were opening and closing, but I still couldn't get any spark. I replaced the worn strap that grounds the guts of the distributor, as it was down to just a few strands of wire. No spark. I tried a jumper cable to ground the engine in case it was a bad ground strap. No spark. I put in another distrtibutor. All was well.

After setting the timing by ear, I headed out to gas her up and to check for pinging under load. When I slowed to make a turn about a half mile from home she died. Now I'm back to the same place. power to the coil, points doing their thing. No spark.

What am I not thinking of here? I'm hoping that the group's collective wisdom can point me to some simple problem that can be easily fixed, leaving me feeling stupid, but with a running Midget./bcforum/images/%%GRAEMLIN_URL%%/wall.gif

The Midget is a '74, if that makes any difference.
 
Condenser?
 
You may want to check the high-tension wire between the coil and the dist (and maybe all of the plug wires too), should be around 70 ohms (I think) for each of them.
Bill
 
THANKS!

I replaced the condensor and coil already. The car ran for a while and then died again. Is there anything that may be "killing" these components?

I'll test the coil wire and the plug wires tonight and report back.
 
Hehe, condencer.
 
Possibly excess primary voltage. Did you remove a voltage resistor or reducer wire when you installed the Pertronix? If you are using a coil designed for less than 12 volts, it could be burning out both the coil and condensor.
 
It's also quite easy to put the condenser in (on the early dizzys) such that the forked lug on its wire accidentally touches the breaker plate... effectively grounding the points just like a kill switch.

A quick check would be to temporarily remove the condenser and see if the car will start. You shouldn't run without the condenser but it will start without one which would let you know if it's at fault.

Perhaps this will help:
https://home.mindspring.com/~purlawson/files/LucasPointsIgnitions.pdf
 
One differing opinion: whenever you make a change in the electrical system and it works for a while, then quits, I immediately suspect a bad connection somewhere--probably something loose and coming open or shorting. You disturbed something that was intermittent, it held for a while, and then stopped working.

In any case, if it's reliably not working, you should be able to trace the problem with a voltmeter. Don't guess whether the condenser is shorted; measure the voltage across it with the points open. If it's shorted, you get zero. Measure the voltage at the supply side of the coil--if it's zero, you are disconnected somewhere. If you have voltage at the supply side, disconnect the other terminal and see if it has voltage on it; if not, the coil is open. Simple tests like this can eliminate a lot of guessing.
 
RonMacPherson said:
Possibly excess primary voltage. Did you remove a voltage resistor or reducer wire when you installed the Pertronix? If you are using a coil designed for less than 12 volts, it could be burning out both the coil and condensor.
Click to expand...

i agree with Ron
check you specs what voltage is requied to the coil personally dont know but im sure some here could tell you
also were are you checking for spark at a plug lead or the coil lead??
also try diconecting the power to the coil and check resistance through distrubiter points open and points closed make sure its not continuilly earthed (had this happen to me 1 stand had busted away and earthed my system out )
hope this might help
 
This sounds most likely, that the coil supply resistor was removed in some way.

Otherwise, simply testing the ignition system would do best.

Remove dist cap and rotor. Main (coil) HT (high tension) wire (called the secondary wire) close to a ground (1/4 inch).

Use a test light with the ground clip on a ground (battery)

Look to see if the points are open.

If no, turn the engine until they are open.

Ignition on.

Check the primary (small) wire (the one from the coil) for power. The test light should light up when it is touched.

Check that the moving part of the points also has power.

Rotate the engine until the points are closed.

Check that the moving part of the points do not have power. (it is grounded by the stationary point)

If this is the case, try opening the points with the test light. (Don't touch the metal part while doing this, and don't touch the HT wire. They both can give a mild shock)

The coil should spark. If it doesn't, the points could be slightly burned.

Try using the test light to ground the moving point to the distributor ground. If that produces a spark, try cleaning the points with fine sand paper or nail file.

However there is a reason they were burnt. Either the condensor is defective (wrong capasitance), the coil is defective (wrong inductance) or the supply voltage is incorrect (supply resistor is defective or non-existant)
 
Coil could be getting hot and cutting out. I have seen this before. Also could be someting as simple as grease on the points. I put in a set of new points and they quit and I had to sand and clean them. Try running a piece of clean newspaper through them with them closed to remove and residue.You have to pull it straight or it will tear.
 
Thanks! I have a lot of things to try now.

I'll work through the lists that you have provided and report back with the results.

It looks like I'll have to wait until the weekend. My father-in-law has been in the ICU for almost two weeks now, and the things that we have put off in order to spend time with him are getting out of hand.

Here's what I do know about the ignition system. There has always been something close to battery voltage coming into the coil. There is no ballast resistor, but I don't think a '74 ever had one. When checking for spark, I have been using my timing light on #1 and also on the secondary coil wire.

The Pertronix was using the ubiquitous Bosch blue coil. I put in a new set of points, a new condensor, a new cap, a new rotor, and a new wire to ground the plate that the points mount to, and still got no spark. I swapped the coil with a new one the has "do not use with ballast resistor" printed on it. Still no spark.

I thought a few bad words but managed not to say them out loud, and then put in a rebuilt ditributor that came with new points and condensor. I got spark.

I drove a half mile, and lost spark. I repeated those same words to myself a few times and then came here.
 
Re: Thanks! I have a lot of things to try now.

After you family is no longer needed at the ICU- then I think that it may be good to go back to Advance or Pep Boys and get the cheapest "no resister" coil that they have and put it in just to verify that yours is not dying upon heat-up (which is common when a coil is going bad, whether it is old or brand-new).
Bill
 
Re: Thanks! I have a lot of things to try now.

My wife spent 10 days in the hospital last month so I can imagine how you are feeling. While I know your car is probably a good way to take your mind off your family's current medical situation... by all means worry about your family first. The car can always be sorted out later.

When the time is right to sort this out, please go back to my first post and download the PDF I posted a link to. It has a troubleshooting section for the ignition system. And during those tests, please look for spark directly on a plug and don't use the timing light. The light isn't part of the ignition system and if there's a problem with it... you could be chasing this for a long time.
 
Re: Thanks! I have a lot of things to try now.

Steve, Replace the rotor ,replace the rotor, replace the rotor, You will not be able to see the failure just replace it.---Keoke
 
One Less USAF Vet

MSGT LaVerne Charls "Bud" Riley reported to St Peter for assignment to new duties Friday morning. I'm glad that his suffering has ended, but sure will miss the guy.

While we were looking for paperwork and pictures, I found a scrapbook that his mother had made for him during the war. It gave me a new perspective, as I hadn't thought a lot about the people who were waiting at home. She had news clippings and letters that tell the same stories that he had shared, but you could read between the lines and see her pride and her worry. It was touching to see into the thoughts from 60+ years ago as if they were now.

For the vets on the board, here's a bit about his wartime service. He and his brother, Bob, volunteered for the Army Air Corp in 1942. Both were already pilots, but Bud's eyes were not good enough for the Army to trust him with an engine, so he ended up flying gliders and also flying right-seat on the C-47's that towed them, retrieved them, and dropped paratroopers. I belive his wartime rank was Captain, but he never got back up to that rank in his post-war career.

He flew a CG-4 with troops and an artillary piece into Normandy a day or two after D-Day. The Resistance smuggled him back to one of the beaches where he was able to catch a British ship back to England where he rejoined his unit (I believe it was the 94th FTS, but can't swear to that). After that he flew CG-4s into Belgium and Holland several times.

As landing areas became secure, he would pilot a glider or co-pilot a C-47 on retrieval missions for whatever gliders were reuseable. They would fly low and slow over the "goal-posts" and snatch the nylon tow-ropes to jerk the gliders into the air. He said that was quite a ride, regardless of which end of the rope you were on.

There were not a lot of useable gliders to retrieve, as the pilots who survived one mission quickly learned that survival is all about getting out of the glider as fast as possible. They learned to deliberately knock a wing off on one of the poles that the Germans planted in the fields to make landings difficult. The hole that left behind was an excellent emergency exit. He said that his best and "safest" landing was when he managed to catch a pole on one wing and a tree on the other. The remains of the fuelage slid into a hedgerow so the troops had cover as soon as the dove through the two new exits.

Bob ended up flying P-38s in Africa and then going back to Wright-Patterson as an instructor. After the war, he was a test-pilot, except for a stint flying P-51s in Korea.

Anyhoo, I've rambled off-topic long enough. I'll be back to sorting out my ignition problems in a week or two. In the meantime, a big THANK YOU to all the vets on the board.
 
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