Electrical: No Power to Distributor

[valleyguy]

Changed points and condensor in my 2R6 truck; set gap. Truck won't start now and no spark showing in distributor when I crank starter; Checked primary wire going to coil (positive side) and there is power. Wire from coil (negative side) going to the distributor shows no power. Bad coil? something else?

Thanks,

Joe D.

[PackardV8]

It was running before you changed points and condensor and now it isn't. Most likely, something you did or didn't do during the tuneup. Check the ground wire inside the distributor. Check the wire which connects the points to the coil. Replace the condensor with the old one.

jack vines

[valleyguy]

Jack, appreciate your help. An electrical guru I am not... I have attached two photos. Ome before and one after. I did change the wire coming from the distriibutor since the old black one looked a little frayed. The new one is red. I noticed that that particular wire (coming from the dist) comes through a rubber connector so obviously not grounded; not sure what you are referring to when you say "ground wire). I also changed the condensor. Notice that the Blue connector at about 7 o'clock (in both pics) has no connection (and didn't when I got the truck) and there is a red wire that looks like it may have gone there (visible in the second pic); I'm not sure what that was, but the truck was running without it. So... to recap the only things I changed were the points, the condensor and that new red wire. I did create a momentary spark when I was messing around getting things back in place, so I thought I might have blown a fuse or something. Checked my two fuses and they look ok.
Any ideas appreciated.

Joe D.

[jclary]

Don't hold me as an "expert" on this, but give this a try. Slightly bend the center contact on that rotor button "up" just a little to make sure it contacts the carbon contact in the center of your distributor cap. When you place the rotor back on the shaft, do not push it all the way down. If it needs to go down further, the distributor cap will take care of that when you snap it back in place.

Once done...crank the engine over and let me know what happens. That was how I solved the mystery on one of mine that wouldn't start after I had "fixed it!"

[valleyguy]

John, I'll certainly try that tomorrow, but can't see how that would be my problem, since I did'nt change the cap or rotor (I had done that a couple of weeks ago.
)
Thank,

Joe D.

[carussell]

Inside '57 Hawk 289 Distributor

Attached are distributor images from my '57 Hawk V8. This is essentially the same and yours should appear very close to this. Mines a little dirty, but you get the general layout.
The black wire at the bottom is the ground and should connect from the condenser mounting plate to the distributor body at the clip that holds the distributor cap.
The "grayish" looking wire is the "positive" and should run from the insulated terminal entering the distributor body to the points; the "positive" side - black wire - of the condenser should also connect there (at the points). Make sure the end connectors on both of these wires are not touching the distributor body; that will short the circuit to ground, will not allow spark, and will burn out your coil if left for very long.
Mind you, the negative side of the coil is just a grounding circuit for a transformer; every time the points close, the circuit to ground is completed and current is "pulled" through the coil's primary winding (the coil is a simple step-up transformer). The field created from this action - on the "secondary" of the coil - produces a much higher voltage (due to more windings than the primary) and creates the "spark" that goes from the top of your coil to the top of your distributor, which in turn - "distributes" that high voltage via the rotor to your plugs at precisely timed intervals. I hope this helps.

[Rerun]

Joe,

An essential part of the ignition circuit is the wire that grounds the distributor breaker plate to the distributor housing. Since the breaker plate moves with the vacuum advance mechanism, there should be a very flexible wire between the breaker plate and the INSIDE of the distributor housing. It appears that a P.O. of your vehicle ran the red wire from the blue crimp terminal out between the cap and the housing to ground. Not good, as it will keep the cap from seating properly. Plus, this wire is too stiff for the job anyway. You can see this wire in the pics that carussel provided. Actually, it looks like this wire may be be broken in his distributor, as well. This wire is constantly flexing when the engine is running, and it is very common for them to break.

The engine may continue to run with this wire broken or missing, but making the ground through the spots where the breaker plate touches the housing adds a lot of resistance to the circuit. This will greatly reduce the output of the coil.

The other thing that I see on your photos is the terminal at the end of the condenser wire. It looks like it may be touching the distributor housing. If it is, NO SPARK. It would be electrically the same as having the points closed all of the time. Bend it in so that it can't touch the housing. Same goes for the other end of the new red wire you put in. Makes sure that the bare wire at the insulator bushing it isn't touching the breaker plate.

Hope that this helps.

[gordr]

I would say you have a short to ground someplace. First things first: if the battery is installed properly, with a positive ground, you need to reverse connections on your coil. If the truck has been switched to negative ground (six or twelve volt) disregard this. To test for a short to ground, turn the engine until the points are visibly open, switch on the ignition, and disconnect either small wire to the coil. If you get spark when breaking and making that connection, then there is short within the distributor.

I would hazard a guess that maybe you got one of the insulating washers in the stack on the points base on wrong. Easy enough to do.

Remember that the breaker plate moves when the vacuum advance operates. the wires within the distributor should not be ordinary hookup wire, but should be copper braid or the ultra-fine stranded "flexy" wire. There should be a wire from the stud on the points to the feed-through bushing in the wall of the distributor (another place where a short to ground can occur), and there should also be a ground wire from a screw on the breaker plate to a grounded screw on the distributor wall. Both should be flexy; the ground wire need not be insulated.

If you have a junk later-model V8 distributor on hand, the entire primary lead for it is made of that flexy wire. You may also find some at your FLAPS. Regular hookup wire will work for a while, but it may eventually fail from fatigue cracks, and this will happen, without fail, when you have a suit and tie on, and are late for an important engagement.

[carussell]

Joe, You can see this wire in the pics that carussel provided. Actually, it looks like this wire may be be broken in his distributor, as well.

I was about to edit my post stating that the wire is not actually broken in my images, it's just turned at an odd angle. I was trying to get quick images for assistance in this post and did not move the wire to give a better appearance. My 289 V8 runs fine!

Just an FYI - the distributor circuit is essentially the same on negative or positive ground, 6 or 12 volt, 6 cylinder or 8 cylinder. The only differences will be polarity of the coil, battery common (ground) being negative or positive, and the number of plug wires. The distributor internal wiring should be the same; it always performs the same basic function.

[Mike]

If you have a junk later-model V8 distributor on hand, the entire primary lead for it is made of that flexy wire. You may also find some at your FLAPS. Regular hookup wire will work for a while, but it may eventually fail from fatigue cracks, and this will happen, without fail, when you have a suit and tie on, and are late for an important engagement.[/QUOTE]


On distributors with movable breaker plates, it's important to make the wires to the points, and the ground for the breaker plate, out of very flexible wire. You can try to find suitable "pig tails" at auto parts stores; or you can make up your own. Wires inside the distributor are more flexible if they are as long as possible. I like to use a grommet for the points' wire, and run the ground through it, to a screw on the outside.
Special care is needed when soldering terminals to the ends that will be inside the distributor. You need to use heat sinking clips and be pretty quick, to prevent solder wicking up the wire, making it rigid. Crimp terminals just aren't as good, unless you have some pretty expensive tools.
You can't beat "Dean's Wet Noodle": http://www.robotcombat.com/products/...cessories.html .
Mike M.

[Rerun]

I was about to edit my post stating that the wire is not actually broken in my images, it's just turned at an odd angle. I was trying to get quick images for assistance in this post and did not move the wire to give a better appearance. My 289 V8 runs fine!

Glad to hear that the ground wire is OK. It really looked questionable in the picture. I have replaced a number of them that had broken conductors, but the insulation was still intact, causing an intermittent problem as the advance moved. Really makes troubleshooting fun! I prefer the flat braided type, if you can find them. On occasion, I have cut the leads off worn electric motor, generator, or starter brushes and used them for this purpose by adding a ring terminal to the cut end.

[valleyguy]

Wow, lots of things to look for; I'll start over again, a little more carefully this time;

Gord, one thing I need clarification on is your statement: "I would hazard a guess that maybe you got one of the insulating washers in the stack on the points base on wrong. Easy enough to do." Can you elaborate, and which location is this?
Thanks,

Joe D.

[gordr]

Joe, somethng about that picture just didn't look quite right, that's all. Usually you have several insulating washers, and sometimes also a separate fiber sleeve that keeps the screw from gounding against the hole in the support bracket. If that gets left out, shorts will happen. Newer moulded washers usualy have asleeve for that purpose moulded into them.

Same caveats apply to the washer stack on the screw that serves as terminal on the side of the distributor case.

[valleyguy]

OK, you guys were all right; It must have been something touching/grounding out. I replaced the primary wire with one a little smaller and more flexible, not ideal but hopefully it will work ok. The PO had given me an old extra distributor that had no parts left in it, except the ground wire!, which has a end clip that was designed to fit down into that notch in the dist housing, but still not interfere with the cap fitting on. Its an old scrungy wire but its not broken so I'm re-using it. Then, I doubled checked to make sure nothing was touching, cranked the motor and now I have spark. I'll set the points tomorrow, and hopefully get the old girl running again. Many thanks to all of you.

Joe D.

[carussell]

Glad you were able to get it going!