No power to the distributor

Rocky Rocket

Rocky Rocket

Junior Member
At a loss and embarrassed... I installed a new dash wiring harness, new coil, new amp gauge, new ignition switch, anti theft cable to the distributor and brand new distributor, all repo stuff of course. i had one brand new coil i discovered was bad after OHMing it out. Replaced that coil with a good one. i have 6V to the coil but i cant get power or very faint spark to the points. Cant get the coil wire to spark to a head bolt. i jiggled the cable to the dist. tightened and backed off a little incase it was shorting out on the distributor housing still nada. Gotta be something simple I'm over looking, hell I've replaced everything from the key to the distributor. Any ideas? I have good grounding using 4AWG cables from the block to the frame and battery to frame and bell housing.
 
With the key on and the points open, use a digital volt meter and with the positive lead connected to a good ground (preferably right to the + battery post) measure the voltage between the following points, in order:

1- Battery negative post. Make a note of the exact voltage.
2- Fuse block or lug on the starter.
3- The terminal box lugs (both sides)
4- Both sides of the ammeter.
5- Ignition switch terminal with the wire from the ammeter or terminal box going to it.
6- At the points.

If any of these test points measures more than 0.2 volts different than the battery post, you will have isolated the issue.
 
Paul has the right approach. It would help to have a little current flowing. You could use a test light between ground and the movable point to supply the current, or a small incandescent bulb in the same electrical position. Resistance anywhere in the circuit would only be picked up with some current flowing.

Having the points closed is another good test but only keep the ignition on for a few minutes so that you do not burn out something.
 
Ignition key OFF! With a multimeter or test light check for a ground (with points closed). Using wireing diagram, Starting with points and working back to firewall terminal block. Check ammeter and ignition switch connections for ground. Good hunting!
 
If you don't have test equipment or you are old school like me, unscrew the ignition cable from the distributor. With the ignition key turned on, scrape the spring-loaded tip of the cable across a cylinder head nut. The tip should have a pretty good sparking going on, not one strong spark, but several small ones like you see jumping around from Dr. Frankenstein's laboratory equipment. If there is no sparking, the trouble lies upstream in the wiring. If the tip does spark, the problem is inside the distributor. If you have installed the so-called "modern" upper plate with the scraper on the bottom side, replace it with the original style. Lots of complaints have stemmed from the use of the scraper plate.
You changed coils and found a good one. If you can't get a spark at the tip of the ignition cable and hence to the ignition points, the coil wire will not give a strong arcing spark between its tip and a cylinder head nut when the engine is turned over with the key on. You've got to get a good spark between the points before you can get a strong spark from the coil. If you have good spark at the tip if the ignition cable, between the points and from the ignition coil to a stud nut, the electrical part of the mystery should be solved. You just have to time the ignition properly and set the points gap between 0.018" and 0.022". Assuming the fuel system is up to snuff (carburetor), the engine should start right up. Fine tune the timing from there for the best compromise between a good idle and power.
Marshall
 
Good advice above...

This won't help you now, but in the future don't go in replacing a bunch of parts like you just did, only go one at a time. If that part checks out go to the next, etc. Now you have a myriad of checks to do and it's possible, quite probable, that with so many crap reproduction parts, you have more than just one giving you trouble....
I learned that many years ago:)
 
hotwire one at a time to trace fault .... simple hot wire.jpg
 
Also, should the engine still not start after ensuring the electrical portion is in order, remove #1 spark plug and either pour in a little gasoline or spray starter fluid inside the cylinder. Replace the spark plug and try to start the engine. If it at least fires and tries to run, the problem is no longer ignition - it's fuel delivery. Make sure the carb float's needle isn't stuck inside the seat, which will not allow fuel to enter the float chamber. Tap the carb above the fuel inlet with a small hammer a couple times to free up a stuck needle in its seat. This happens because the crap gas we have to buy these days turns sticky if not in use after a while. This sticks the needle in the brass seat, shutting off the flow of fuel. I just ran into this problem Monday in a 1924 Model T Coupe that hadn't been started since the owner was killed by a school bus one year ago yesterday. The needle had to be removed with a needle nose pliers (or as my wife calls them: nodle-neese pliers) because the old fuel had almost glued it up inside the seat. Make sure you are getting fuel into the cylinders. If spraying starter fluid makes the engine start, you've still got fuel delivery problems between the cylinders and the gas tank.
Marshall
 
I stick to the A&L capacitor/condenser. They are reliable. Make sure that little wire on the underside of the points plate is good. They flex per the design so they can crap out over time. The breaker points control the ground path so the whole breaker circuit has to have continuity for it to function.

The coil gets power from the generator side of the terminal box so that the ammeter will show you when the points open and close per the 1929 Service bulletin. Some folks swap the ignition switch to control the power to the coil like a modern system so that would put a need for a direct circuit from the coil to the breaker instead of the way the OEM circuit was designed. It will work either way.
 
it was my new Rex distributor points with the brass slide on the bottom plate. i switched it out with the old style points.
6 solid volts to the points! back on the road!

good call!
 
Glad to hear your were able to locate the problem. Unfortunately that brass ring setup on the bottom plate is a breakdown waiting to happen. The wire connection is almost failure proof.
 
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