no spark

[Ordsgt]

Brand new engine installed in a chassis no body. Engine cranks fine. 6.3 volts at Battery, both posts on coil and at points. Spark jumps with screwdriver from point arm to points. New coil still no spark installed another new coil still no spark. new coil wire still no spark. no spark from coil to head with just wire and no spark at any plugs. New points, condenser and coil wire. Gap on rotor and points is in spec and 3 different boats ( Distrib top). I am stumped

[Marshall V. Daut]

Try another condenser. Even the so-called "short-proof" ones can be bad right out of the package. I experienced that this past week when I installed a new one. No spark arcing from the new coil, but the points sparked. Still, though, no start. Putting in a grungy old condenser from my ignition parts box solved the problem. The engine fired right up. The new condenser just came this week and although it's supposed to be short-proof, this one was bad.
I'm not saying a bad condenser is your problem, but it's unlikely a second condenser will also be bad.
Marshall

[Ordsgt]

I have the modern points in distributor that was not producing spark. replaced with a 2nd distributor with original points all new with same results. no spark to plugs or to top of distributor. Placed a clear cap on and no spark from rotor.

[Gary WA]

Originally Posted by Ordsgt

I have the modern points in distributor that was not producing spark. replaced with a 2nd distributor with original points all new with same results. no spark to plugs or to top of distributor. Placed a clear cap on and no spark from rotor.

What kind of switch do you have popout or standard on/off? is your end screwed in to far in distributor?

[Ordsgt]

standard switch and screwed cable in till would no go farther. Will back it out some and see if that makes a difference

[Ayers1]

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Originally Posted by Ordsgt

standard switch and screwed cable in till would no go farther. Will back it out some and see if that makes a difference

That could be the problem. If you screw it in too far you short out the lower plate. I put mine in just slightly past when it makes contact. Hope that's all it is!

[Ordsgt]

Backed it out 2 turns, no change

[Ayers1]

It sounds like you have spark at points but not at cap when you hold it close to the head, is that correct? Double check the ignition switch and make sure it is working properly. I had one a few years ago that would work intermittently. Finally found it after swapping the coil and distributor and nothing changed.

[Bigsnapper43]

I bet the plug from the key is still screwed in too far. Don't ask why I would say this!!!

[Gary WA]

Originally Posted by Ordsgt

Backed it out 2 turns, no change

if you screwed in to far could have bent the contact!

[Ordsgt]

I will take it all apart tomorrow and check everything again. Been working on the for the past 6 hours and will give it and me a rest and continue when I get up

[Ayers1]

Originally Posted by Bigsnapper43

I bet the plug from the key is still screwed in too far. Don't ask why I would say this!!!

I think we've all been there at 1 time or another. Usually I have the distributor out and screw it in until it makes contact, then turn the distributor around to the proper install position. That's usually not more than 1/2 a turn. It works for me.

[nkaminar]

Check for shorts or broken wires inside the distributor.

Here is a simple test for your ignition system.

1. Crank the engine over by hand until the points are fully open then check the gap. It should be 0.020 inch.
2. Turn on the ignition and measure the voltage at the movable point. It should be the same as you battery voltage or about 6.4 volts for a 6 volt car or about 12.7 volts for a 12 volt car.
3. Crank the engine over by hand until the points are closed. With the ignition on measure the voltage at the movable point. It should be close to zero, less than half a volt. Do not leave the ignition on for more than a couple of minutes or you may burn out the coil.

If the ignition system fails #3 then dress the points with 400 grit wet and dry paper and after that clean the grit out by sliding cardboard through the points or snapping them closed. Then try that test again.

If the ignition system fails #2 then look to see why you are not getting voltage to the points. Trace the voltage from the ignition switch or battery all the way to the points. Look for shorts or open connections or broken wires or bad components, like the ignition switch or ammeter.

[rotorwrench]

I always check continuity through the breaker circuit to make sure that the circuit is open when points are and closed with breaker closed. An Ohm meter is a person's most used tool when checking electrical systems. I also keep several condensers around that I know are functional. Another good tool is a spark lite tool to check spark from the coil. Polarity is another check that it does.

[CT Jack]

Assuming your ignition switch is good, disconnect any accessory wiring that is connected to the ignition switch. Sometimes the best temporary solution for solving a problem like yours is to completely bypass existing ignition wiring. Run a temporary wire from the (-) pole of the battery to you ignition switch. Then run another wire from the other side of the switch to the (-) pole on the coil. Make certain the (+) wire from the coil is going to a good clean ground. If you follow the suggestions given in #10 & #13 your engine should start.

[eagle]

Sounds like you have been throwing the kitchen sink at it. MUCH better to use the wiring diagram and a voltmeter and find the TROUBLE before replacing parts. Simple test, power side of coil should be battery at all times, with ignition switch ON, point side of coil should be battery when points open, turn engine slowly with crank, point side of coil should drop to 0V when points close. Keep the distributor open (so you can see the points) so you can trace back the lack of ground...Is the point arm 0V? Is the ign switch contact 0V? Its not complicated but requires methodic troubleshooting. RESIST throwing parts in, you will only introduce additional problems.

[Ordsgt]

did use the diagrams and meters to measure voltage and resistance unable to isolate the problem. The spark at the points is weak compared to what I normally see. Just to make clear this is in a chassis not a complete car but the wire harness is a Model A there are no lighting or accessories involved

[Ayers1]

Ok, I'm reaching a little here. You said new engine, I assume freshly painted? Guys, could it be the distributor isn't grounding through the head like it should? Just trying to think outside the box a little.

[nkaminar]

Voltage is not current. You should be getting about 4 to 5 amps through the points when they are closed. Put your multimeter on the 10 amp scale in hook it in line (in series) with either of the low voltage leads to the coil. Close the points by turning the engine over with the hand crank and read the current. Report the measurement to the group. If you are not getting the normal amount of current through the points then there is some added resistance somewhere. It may be a grounding issues as Avers said above or a bad contact somewhere. I have found that 90% of electrical problems can be traced to bad connectors or bad contacts. Everything should be bright and shinny and tight.

One other thing to check is the polarity of the coil. A minor point and probably not your problem. You can get a polarity checker from the suppliers, see https://www.snydersantiqueauto.com/p...6303&cat=41753

[Ordsgt]

everything is new paint. will pull dist and remove paint at base. Engine has additional ground strap trans to batt ground