Electrical Issues.

[chargerdave]

I am new to this forum. For the past 4 years I have been periodically working on a 56 Dodge C3 truck. I had the 230 six rebuilt, and now I am converting it to 12V Negative Ground. I know that a 56 was already 12V, but my engine was purchased separately and it was a 55 with a 6V starter.

All of my gauges, lights, etc., are already 12 V. My problem is I am now to the point of trying to fire up this engine for the first time since the rebuild, and have had no luck. I kept my 6V starter to keep the stock appearance of the foot actuated lever starter. I took my On/Off Ignition switch and wired the post labeled coil to the + terminal on the coil, and ran the - wire from coil to the points side of the distributor. I wired a ballast resistor in between the ignition switch and the coil. When I first tried to start it, turned over just fine but no fire to plugs. I re-gapped my points, rechecked wiring and timing to make sure #1 was at TDC, but still no fire past the distributor. Now I have a new problem. The last two times I have turned the key on so I could then push the start button, the wire to the ballast resistor has gotten so hot that it smoked and burnt up two ballast resistors. I am frustrated and out of answers. Since this is a lever actuated starter, there is no solenoid, or relay to run a wire to bypass the resistor just during the start procedure. I know I sound like an idiot to most of you guys, but need some answers. Appreciate any help you can offer.

[B1B Keven]

Did you change the coil to 12v?

[Dave72dt]

You've got a SHORT somewhere in the primary ign circuit. Unhook the coil and try again. Wire not hot, rehook the coil and unhook the dist. Continue testing and working your way down the circuit. Could have a cond grounding out or points welded shut, wire inside dis touching ground.

[chargerdave]

Yes, I have a 12V coil that requires an external ballast resistor.

[catfishcuz]

If the ballast resister is getting hot you have it wired backwards.

[greg g]

Did you swap the coil leads ign to pos, neg to points. 6v starters are 2x more robust than 12V ones and is won't care about the extra voltage. For short testing purposes you can bypass the ballast resistor. You need it for prolonged running but not for a 5 or 10 minute lets hear it run session.

[Dave72dt]

Resistors WILL get hot. Those little porcelain resisters will often smoke a bit first time used and should make no difference which way you feed them, strictly an in and out. The wire to the resister shouldn't get hot so it's letting too many amps go through if it's melting the insulation, especially if it's the 6v gauge wire. Somewhere in the circuit all that voltage is going directly to ground and is the reason you're not getting any spark to the plugs.

[chargerdave]

Yes I swapped the wires so the power wire from the ignition switch goes to + terminal and the negative wire to the points side of the distributor. The only place I can think of a ground is the ground strap that grounds the points to the breaker plate/distributor housing, that I was told was needed.

[Dave72dt]

Pull your primary wire off the distributorand turn the key on. I'm assuming an external wire attachment point on the dist. That post that goes from the inside to the outside can ground out if the insulators are bad. Try disconnecting that ground strap. I'm thinking it's installed wrong.

[Dave72dt]

Pull your primary wire off the distributor and turn the key on. I'm assuming an external wire attachment point on the dist. That post that goes from the inside to the outside can ground out if the insulators are bad. Try disconnecting that ground strap. I'm thinking it's installed wrong.

[mechresto]

Yes I swapped the wires so the power wire from the ignition switch goes to + terminal and the negative wire to the points side of the distributor. The only place I can think of a ground is the ground strap that grounds the points to the breaker plate/distributor housing, that I was told was needed.

there's a ground strap on your points? there should not be one, one side of the points are connected to the coil, the other side is already grounded via the breaker plate. if you or someone else has connected an auxiliary ground, remove it. some models have a ground strap from the breakerplate to the distributor housing, early model vac advance units had an issue with bad grounding, if yours has this braided strap from breakerplate to housing leave it in.

as to your ballast resistor, it reduces voltage at the points "during running only" it's function is to keep point arcing to a minimum. a 12v system needs straight battery voltage to the points when cranking to provide the hottest spark possible to avoid hard starting issues, so the ballast resistor needs to be by-passed during cranking. you'll save yourself a bunch of headaches in doing so.

It's no huge deal wiring in a by-pass on a conventional key start system, with a foot starter there's a fairly simple way, if going for a stock appearance you just have to hide one wire. If you're interested, fire me an email and I'll show you how it's done.

Bryan

Edited April 13, 2012 by mechresto

[chargerdave]

I also have a spare distributor from that same era, but can't use because the shaft is seized, and it has the same ground wire from the breaker plate(which mounted stationary to the inside of the body of the distributor to the hold down screw for the points. This is how both of these distributors were set up when I got them, and they came from two completely different sources. Once one on the junk rusted together engine the truck came with, and the other I bought off of EBAy.

[HanksB3B]

Are there numbers on the distributors?

What is the correct Distributor Number for your truck? I have two rebuilt units one is my back-up and the other is for sale (if you find that to be the problem and it'll help you out).

Hank

[Dave72dt]

Troubleshooting electrical requires a systematic, logical approach. Explain in detail what and how you've been testing. Maybe some pictures. What have you replaced, including wires and what with as far as wire gauge size.

[chargerdave]

Well, opened up the distributor and moved the ground wire from the points mounting screw, to the condenser mounting screw. The other end is soldered to the breaker plate that attaches to the distributor body.

Also moved my battery ground cable from the frame to the engine block to get a better ground. Tried to start the engine and it turns over real fast but doesn't try to start. Seem to have solved the short issue. No more overheating wires or burnt resistors. Now to find out why it won't start.

[Don Coatney]

The distributor hot wire (shown in the picture below under the screwdriver blade) must not be grounded. The ground wire also shown connects the breaker plate to the distributor body. Both of these wires must be flexible as they move with the advance mechinism.

[Alshere59]

As stated the hot side can not be connected to ground. The electrical path has to flow as shown in this pic.

http://en.wikipedia.org/wiki/File:Car_ignition_system.svg

If you have it right you should be getting spark at the plugs. Are you? A number of ways to check this the simplest is with a screw driver in you spark plug boot and holding the shaft of the screw driver next to the block and watching. Or you can buy a cheap tester that goes in line like this if you are like me and have difficulty seeing it without getting shocked while using the screw driver.

http://www.amazon.com/Lisle-20610-Inline-Spark-Tester/dp/B0002STSC6

If you have spark and since you mentioned the engine was rebuilt, have you verified number one cylinder is at top dead center on the compression stroke with your rotor pointing at the number 1 spark plug wire? If it wasn't indexed or was off by a tooth or so when it was rebuilt it may not be where the manual shows it.

To check.

Take the plug out of number one cylinder and put your thumb over the hole. Turn the engine over until you feel the compression of the engine.

I try to turn it manually with wrench on the crankshaft nut or by pulling the on the fan once i start to feel the compression. This gives you better control while lining up your timing marks to TDC without going past the marks.

NOTE: Remove all of the plugs to make it easier to turn if pulling on the fan and that also ensures has zero chance of firing. Then once the timing marks are lined up look at the distributer with the cap removed. Is the rotor pointing at number 1 plug? It should be at the 7 O'Clock position but it may not if the oil pump wasn't indexed. (Research indexing the oil pump for how to change it.)

It will work at any position as long as you line up the rotor with the wire you have going to the number 1 plug so your choice just remember when reading the manuals for our cars that it is different. At any rate move your spark plug wires around or turn your distributer until the rotor is pointing directly at the wire leading to number one plug. Check your firing order then put it back together. Verify firing order again and see if it starts.

Edited April 14, 2012 by Alshere59

[Dave72dt]

Next part is to finish checking the primary ign circuit. Do you have power to the point? Do they open and close? With the key on, cap and rotor off do you have little sparks between the points when they open and close. You can do this manually with a screwdriver or by the starter. Until you have those little sparks,it doesn't matter where the plug wires are, it won't start. If you have that, you've completed the primary circuit testing. The coil wire should be producing spark at this time.

This is the beginning of the secondary ign system. If nothing, you have a bad coil or coil wire. Next is the cap and rotor and when timing comes into play.

Edited April 14, 2012 by Dave72dt

[chargerdave]

Checked the spark at the points with a screw driver, but got nothing. I tried two different coils, and got same result. No spark at the points.

[Dave72dt]

The condenser is the most likely culprit at this point, again assuming you have power to the points. Double check that. A little sand paper run between the points won't hurt as they may have glazed over.

[chargerdave]

Well, replaced new condenser with another new condenser, and a new lead wire post and insulators on body of insulator, and also discovered a short on the wire to the points. I now have a strong spark at the points, but still no spark at the plugs. I have installed a new rotor, new wires, new coil wire and coil and a new distributor cap, but still no spark at the plugs. Beginning to consider a problem with the distributor cap.

[Dave72dt]

With the coil wire close to a ground source, turning the engine over and key on should produce sparks. Do you have that? The cap is next in the secondary ign circuit, then the rotor, plug wires and plugs.

[JBNeal]

A couple of things: verify that the contact at the center of the distributor cap is in place, as I've seen these fall out, never to be seen again, requiring cap replacement; also verify if the contact will mate with the rotor, as I've seen a "correct" cap fit onto a distributor, but the contact and rotor were too far apart for any spark to be transferred. The latter problem was eventually pinned down to an improperly boxed part at the factory.

[MBF]

Try another rotor. I pulled my hair out years ago after tuning up a V-4 outboard that wouldn't start. Rebuilt the mag, changed the points, condenser again, bought a new cap and still nothing. Turned out that the brand new rotor that I had just bought was defective. Put the old rotor back in and it popped right off. If you can fire your coil to ground by working the points with the key on, I believe the problem has to be either the cap or rotor. Mike

[mechresto]

Maybe a dumb question---------is your distributor shaft rotating when you crank the engine?