The Stovebolt Site Forums The Shop Area The Electrical Bay Yes. Still no spark

First thanks everyone for all the help on my last thread concerning no spark. Here is where I am at at this point the truck is a 1949 Chevy 3100 6v negative ground. I have voltage going all the way to the points with the gap set correctly and everything checked point to point we are getting 6v to the points and to to the primary and secondary windings in the coil but nothing to the spark plugs. We have changed the coil with a known good coil, changed the points, condenser and coil several times still no spark. Changed the cap and rotor and made sure everything is grounded. I had a friend come confirm everything and from what we both agree we should be getting spark
So what’s next... here are my questions:
With the 6v the engine seems slow to crank and the voltage drops to 2 volts at the coil. Is this normal?
Can the starter be the problem? I did change the switch when I first got it because it was bad. I know it spins.
Can the voltage regulator be the problem? All we have hooked up is a toggle switch that gives power to the coil the regulator is not in the loop. Should it be?.
Not shore what else to check. Any further suggestion?

Thanks
KT

Any possibility that your distributor cap is too tall and the rotor is not making contact with the terminals? Have you checked your grounds to be sure they are clean and tight? A lot of bolters run the negative cable directly from the battery to the lower starter mounting bolt. Just some ideas.

Thank you but yes the rotor is touching the cap. I have checked the grounds and everything is grounded correctly including the distributer.

KT

For a quick check on the ignition system you could run the starter on 12 volts separate from the rest of the electrical system, let the full 6 volts energize the ignition and let the 12 volts spin the starter.

2 volts at the coil primary input (from the ignition switch) is FAR too low. You should see a minimum of 4 to 4.5 volts during cranking, at the starter, and the coil. Have someone test the voltage at the battery posts (not the cable terminals) while you crank the engine. I'm going to hazard a guess you've got a dead cell in the battery. With very low cranking speed and low voltage, you're sending all the juice to the starter and virtually none to the ignition system. The compression will also be very low at slow cranking speed.
Jerry

The battery is new about 3 weeks old. I checked all 3 cells with a hydrometer today. All are good. We checked the battery volts at the Posts and got 6v today.
I read earlier that on a 6v there should be 00 positive cable. Although the cable I have is new from Classic Parts I do not think it’s a 00 cable and the specs do not say. Could it be that simple?

Yep. You need bigger cables.
Also, reading 6 volts on a 6 volt battery indicates a discharged battery. You should be reading around 6.5 volts or higher for a fully charges battery.

Both the positive and negative cable/strap should be at least 1 gauge, but 00 gauge is better/best for both.

Tractor Supply or a farm store or a welding supplier should have them. For the grounds, use a cable rather than a strap, if necessary.

Make sure all connections are clean/shiny. Use a conductive antioxidant copper-grease to minimize oxidation at connection points for battery cables and all ground straps.

Pull the coil wire out of the distributor cap and hold a half inch from a good ground. Remove cap and work points with a screwdriver, don't worry about precision just rattle them around. You should get a good blue spark or at least an orange spark with a blue streak in center. If you do then the starter draw is too great or cables insufficient. If you don't then try a jumper wire from the positive battery post straight to the + side of the coil; this eliminates all the electrical system and any possible problems in it.

Hi. Here is where I am at. Testing the batter posts 6.24 testing battery to starter 6.24 to coil to points 6.24. I unplugged the plug wire to the coil and put my lead in 6.24 that dropped between 4.98 to 5.2 when trying to start. I did bypass the ignition with a jumper wire direct from battery to coil and the readings were the same as when hooked to to the ignition wires. I cleaned the points again and tried to rattle the with no spark at all. I also got a larger gage battery cable. I’m no expert so I appreciate advice. Thanks

If you are getting power to points and when you manually open them you get no spark? (Use tip of screwdriver to open points). Sounds like the condenser is bad. ?? Check the Condenser. Mine went bad after less than 70 miles. Junk made nowadays!.

are the points wired correctly? I had an off brand dual point distributor that the PO had wired the second set to ground.

What is the delco remy number for your distributor?

Model 1|2352 - 1A20

Hopefully you got this fixed but if not make sure the dwell is set properly. You need to make sure that the points are fully closed and that they fully open when they are supposed to. I am no expert either but I had a similar problem that kind of happened out of no where.

I was pulling my hair out checking all kinds of different things and the adjustment was slightly loose I guess and the points "looked" like they were functioning (opening and closing) properly but they were not. They looked closed but they were like .00001 open when they were supposed to be closed. It was crazy but you have to check with a volt meter as you turn the distributor watching the voltage react when the points open and closed.

There is actual equipment that a real mechanic will use to test this but for average joes like us you just gotta do what you gotta do.

You said in your first post you changed coil,points and condensor. Have you changed the coil wire?

Several folks have said the battery is the problem. I think 6.24 would start it. It seems to be "breaking down" while cranking. Either the cells in battery are breaking down or the starter is "breaking down"/taking all the voltage. If you want to know if the starter is bad and taking all the voltage, push the truck to start it. (don't forget to turn the key on). If you want to test the battery, take it out and take it to a place that can check it under a machine load. Your problem will be identified doing these things or you will move to other causes. We are guessing right now. You seem to report all other possibilities are new or checked by you. Right now, we have to believe that.

I think I read one time cranking voltage was 2V next time was 4.98V to 5.2V. Did you edit a post?

All. Thank you for the responses. A friend stopped by and we started at the beginning and retested everything issue 1 seemed to be the insulator on the side of the distributer not properly seated. Issue 2 seems to be a short someplace from the ignition to the coil We disconnected the positive side of the coil and jumped straight off the battery and boom we got spark. Put some starter fluid in and it tried to crank so I don’t think it will be long... we will be rebuilding the carb and moving on from there. Again thanks for all the help.

BINGO! John L.