Have a 74 460 with breakerless ignition in a 65 pickup.Sometimes when driving along at highway speed it will pop very loud just as if you had turned the ignition switch on and off. Last week, out of the blue it decided it did not want to start. After lots of checking , lots of frustration, and lots of trail and error I found out that if I ran a ground wire straight from the battery to the ignition module it will start every time and runs great, and no more popping either! The ignition module does not have any sealant at all left on it bottom side, it has slowly melted and run down the inner fenderwell. Tried to get a new one form two different parts houses and the ones that they say replace it (different color wires at plugs) will not work, no spark at all when the news ones are installed. Put the old one back on and it starts and runs great again. If you are looking into the female three wire plug on my module, the left wire is blue, the top wire is black, the right wire is green. Looking into the four wire plug with the line-up tab to your left, the top left wire is orange, top right is purple, bottom left is red, and the bottom right is white. The only number I can find on the distributor is 12121. Parts houses are of no more help. Anybody got any ideas on how to find a replacement module. I feel like I need to be getting one since all of the bottom of mine is exposed to the elements. Thanks

 

The modules are identified by the color of the plastic piece where the wires enter the module. The most common no-frills module has blue plastic. The early ones were black plastic but the blue should interchange with it. There were I believe brown, green, and yellow modules, possibly more. They all had added features for timing control, mainly for emissions reasons.

The module and ignition system are grounded through the black wire that leaves the module and goes to the distributor. Inside the distributor, the black wire is bolted to the metal body. This wire must have a problem on your truck.

 

Here is your module, and the later module for comparison. The later module used one less wire and "should" work. Only diff I see is your distrbutor may not be getting it's ground. Too early for me to figure it out. I'm usually converting points to Duraspark and use the later module.

 

The choices are
1: Find a matching module. I would watch ebay
2: Rewire a standard “blue module”. You will not use wire #4 BLU in the 3 wire plug. The rewiring would all be on the new module pigtail ends, not the truck harness.
3: The simplest and cheapest choice would be just to use a GM 4 Pin module. Here is a link, I have been using this on my truck for about 2 years, it is my daily driver.
Here is a link... Dirt cheap Ignition



If you choice #2 I can post more info

Jim

 

double post ...............

 

Thanks, surely with all of this info I should be able to get something to work. Will keep you informed, but it will probably be a while, other more pressing work is piling up. Thanks again!