Hello Olds Family, I have a couple concerns in my recently acquired 72 442. My car has the MSD A6L and the switched wire is connected to the IGN spade in the fuse box. It doesn't appear to be very clean power and my MSD does not get the constant 12v that it needs to stay running. When it is plugged in and running, my harness gets wicked hot coming out of the firewall. Today I found an alternative 12v switched plug that was currently not being used, more on that later in the thread. I also noted today that the flasher fuse was blown, it was not yesterday. The question that I have is does anyone have any experience in rebuilding their fuse box? Like taking it off the firewall and cleaning and resoldering any questionable joints.

As for the pink and orange wires connected to a female plug, can anyone identify this? I have looked at a few of our fellow wiring diagrams and I didn't see anything that matched. I have only had the car a few weeks and I am still waiting for my assembly manual and chassis manual. I am including a picture of the plug with attached wires. The single red wire connected is a temporary wire to power my MSD A6L

 

I would use the IGN terminal to trigger a 30A relay to power battery voltage to the MSD box.

 

I agree that you should use an ignition triggered relay fed from a fused wire directly from the battery to run the MSD box. As far as rebuilding the fuse box, the best option is to remove the entire dash harness and remove all of the pins/ terminals. I use a combination of wire brushes, wire wheels (Dremel and bench grinder), and de-rusting solutions like evaporust or metal rescue. I recommend taking pics of the back of the fuse block before removing the wires and terminals so you know where everything goes. Once I have the box re-assembled, I will paint with a coat of matt or flat rattle can clear. It will not get in the areas where the fuse sits, but will protect the outer portion of the terminals.

 

It was already plugged in to the IGN terminal and I couldn't get constant power. Not to mention it blew my turn signal fuse. It was like that when I bought the car. I'm looking for a best solution and it being plugged in to the terminal was overheating my harness until the fuse blew. I will try it with a bigger gauge wire than what I was using to see if that fixes the heating of the wire and the blowing of the fuse. I will also add a relay as suggested. Thank you for the information.

 

Can you draw a simple diagram of what you are describing? I have it pictured in my head but I would like to make sure that I understand what you are describing.

 

Mike, there are two red wires coming from the MSD 6AL.

One is heavy-gauge, about 12 gauge. It needs to go directly to the battery. It is the main supply for the MSD.
One is light-gauge, about 18 gauge. It needs a source of power when cranking and running. This is the signal wire that turns on the MSD.

The IGN terminal would be a suitable connection point for the light-gauge red MSD wire. This only takes a few milliamps.

Good luck with your project.

Gary

 

I understand that and I had it hooked up properly. With the small gauge red wire connected to the IGN spade in the fuse box. It is losing power and it is inconsistent at that connection.

 

Does the MSD and distributor have good grounds?

 

Keep up with your plan to rehabilitate the fuse box connections. When I rebuilt my Olds, I was amazed at the sorry state of some of those connections.

The two easiest things to cut the amperage going through the fuse box and firewall connectors are to operate the headlights with relays and to use a Ford starter solenoid on the purple wire (not the battery connection) to the starter.

It sounded like you had correct MSD hookup... my previous comment was to make sure that readers of this post weren't confused by redundant, unnecessary MSD wiring advice. MSD already has an internal relay that accomplishes what other posters suggested. I should have been more clear on that goal.