I'll try to be as descriptive as possible. Running a Mallory Unilite distributor with Mallory Promaster coil (29440) with ballast resistor (700) and Mallory ignition module. I was out the other day and the car just shut off (no spark). I have already replaced (last year) the ignition module. When it cooled off for a bit I was able to start it and get it home. I tested the ignition module and it was bad again, so I sent it in under warranty and got a new one. I replaced the starter and alternator with new ones I bought here from a member who bought it from Jamie but never used them. I replaced my battery cables with lectric limited cables. I replaced the plugs and wires with Taylor Thunder Volt 83055 I replaced the ignition module and installed a power cleaner (29351) inline. I spark tested the coil and it was weak (yellowish spark) so I replaced the coil with a Mallory canister coil (29219). I have 12v (key on) running from my wiper motor plug connector into the ballast resistor (upper post). That's my power. Red wire from ignition module is also on that ballast post. Ballast resistor (bottom post) goes out to the coil positive post by itself. On the negative coil post I have the brown tach wire and the green ignition module wire. The brown wire from ignition module, I ran a new ground wire to the braided ground wire that goes from the block to the firewall. When I pull the coil wire and test for spark, it will spark once, then nothing. I can make the ignition module trigger with a credit card. Any ideas? I'm pretty sure I have everything wired right according to the Mallory diagram. The only thing I haven't replaced is the cap, and it look ok.
Why are you running your power from the wiper motor? You should be running it from the engine harness. It is easy enough to do it that way. Have a look at this thread, http://www.v8buick.com/index.php?th...ystem-function-tests-and-modification.248990/
Thanks for the link Larry, I will read it and see if I did something wrong. I used the wiper motor connection because I didn't know about the connection inside the harness, and I wanted a quick tie in to 12v to see if I could get the car to start. No I did not connect the R wire on the starter solenoid. Put some dielectric on it and taped it back up into the harness. The starter I removed did have the R wire hooked up.
Larry, from the link you posted above you said: So once I do this, I use this wire from the engine harness connector on the firewall as my 12v ignition wire to my ballast resistor, then out to the + coil correct? What happens if I run 12v right to the coil without going through the ballast resistor? Will is smoke the coil? Sorry for all the questions, I've been having a hard time with this for the last couple weeks... I've replaced damn near everything.
The original wire in the harness that went to the + side of the coil is a resistance wire unless it was modified by a prior owner. The original points system used that resistance wire. A ballast resistor does the same thing as a resistance wire. Use one or the other, not both together. This is spelled out in the unilite instructions. They call it a loom resistance wire. If you don't use one or the other, it will eventually destroy the unilite module. Read the top header. https://static.summitracing.com/glo...MalloryInstructionsunilitedistributor3738.pdf My link explains how to replace the resistance wire for systems that require full battery voltage like the GM HEI.
Ok, so i ditched the ballast resistor completely and went back to the original factory resistance wire to the + coil. You were right to ask why I jumped the 12v from the wiper motor harness. That was a problem. Yes there is 12v on key up, but not on crank, so there was the crank/no start issue. Jamie's starter has the "S" and "R" terminals on the solenoid unlike Powermaster starters. I needed to re-hook up the "R" terminal with the wire I had previously taped back into the harness when I replaced the old starter, and I got power back and good spark. Car fires up and runs again.
OK, as long as you are using the original resistance wire, you are good to go. The starter solenoid provides full battery voltage for quicker starts only when cranking. The rest of the time, the resistance wire cuts down the voltage so the unilite module should live a long happy life.
What is up with that cap in the picture. What does your rotor look like. Isn't one of the terminals twisted 180 degees. (4:30)
All the contacts in that pic are orientated correctly, but I did replace the cap. See how the center button is all pitted? It was also nearly flat across. The new cap button is spherical and smooth. This is the rotor: https://www.msdperformance.com/prod...vice_items_for_mallory_distributors/parts/305
I'm getting 9v from the resistance wire, which is exactly what the module calls for. Thanks again Larry!
