The plastic AC relay pigtail is shot on my 70 442. I bought a new one on-line, but rather than splice the wires I want to remove them from the new connector housing, replace the female wire connectors on the existing wires and insert them into the new connector housing. Simple enough. How do I determine the correct non insulated locking female spade connector (or whatever they're called)? What I can't figure out is if I need 6.3 or 4.8 mm connectors. I want to do the same at the alternator and elsewhere. Also, where would be the best place to get these? I'd rather pick them up locally rather than order on-line. My google search only shows on-line stores which is fine if that's what I have to do. In the old days I'd go to Radio Shack for something like this. Any help will be appreciated.


Old pigtail

replacement pigtail

 

Measure the tangs you want to connect to in order to verify the size you need.

On my 1970 Cutlass, every spade connector is 4.8 mm except headlights, which are 6.3 mm.

Clean the matching spades to eliminate corrosion. Your connector melted because of corrosion between the spade and connector.

 

Or high current draw from the load that the relay controls.

 

Those are Packard 56 connectors. The larger ones are Packard 59 series and were primarily used on headlights. Also, the Chinesium brass terminals you show in your photo above are crap. Do not use them. Correct Packard 56 terminals look like this and are much thicker. They are also silver plated for conductivity.

 

Thank you for adding that.

Even with low, constant current draw, corrosion (resistance) between the spade and connector causes constant minor heating that accelerates the corrosion. A downward cycle ensues.

 

There’s a place called terminal supply Here in the D, they have all the correct ends, been through just what your doing on my 78 Bird, if I can find their catalog, ill Post it
with a tiny screwdriver, You slip out the terminal, replace, slide back in.

 

Yes. The proper way to test a circuit is with a clamp on ammeter which will instantly show the current draw of any circuit. Lacking that it's just a guess.

 

I’ve bought terminals and plastic shells from here:

https://www.clipsandfasteners.com/Pa...-p/w32c031.htm

Joe is absolutely right about the quality of latter day parts.

One fix is to use a tiny gauge flat blade screwdriver to release the terminals from the old shells, give them a light cleaning with a dremel wire brush and hit them with Deoxit 5 which reduces oxidation on old terminals to improve conductivity.

If you dig around under my user name you’ll find a few posts about repairing wiring harnesses and one or two about modifying them for modern equipment too.

My simplistic advice would be to retain the original terminals where possible and substitute reproduction shells where you need them.

Honestly though, if the shells have melted for some reason, that’s an indication of a problem which you should trace out and fix before just fixing the symptom - a melted shell.

I’ve also used terminal supply along the way.

Chris

 

Thx for all the input. Packard 56 terminals are on order.

 

Your connector housing melted because of the dirty connectors causing too much resistance and heating up. Your best compromise is to clean the bejesus out of the existing connectors (like cfair said) and put them in the new housing. The older connectors are better as long as they can be cleaned.and fit tight. Do your best to get all the oil and dirt out of the crimp connection to the wire as well. Sometimes it is best to solder the wire and connector together if possible, but they have to be very clean to do that.

 

By the crimping tool, I’d put new stuff on, I bought a used harness for the melted connectors, crimp, solder, done. You have a restored factory harness that doesn’t have corroded old connectors on. Same for headlamp plugs. And they sell just 1 end if that’s all you need.
They had the factory match for a AC solenoid crimp on and connector, also the trunk light plugs too for a buddys car.

 

I did clean the AC relay connectors today and installed them in the new plug. That’s a short term fix. I will be checking all the connections over time. I had to coax 2 of the headlights back to life yesterday, so they’re next one the list. I’ll throw a fire extinguisher in for peace of mind.

 

All the connections get corroded over time, some worse that others, head lamp sockets take a beating, there in the grill.

 

^^^This. There's a reason why GM eventually moved from the Packard 56 connectors to the sealed Weatherpack connectors.

 

Another little tip: lacquer thinner is great for getting cr*p off wiring. Cleans ‘em right up so you can see the original color and any striping Olds might have used to identify circuits.

While you’re looking closely at the wiring, have a roll of blue tape nearby to mark any frayed, broken or uninsulated wires. That way you’ll have a map of what to fix now or later.

If you’re in restoration mode, start with the high amperage battery-connected wires. These have taken a lot of load for years and sometimes need maintenance. Also look out for the door switch wires that turn on the courtesy lights. Each time the door opens, the wires move (as designed) that means they’ve been worked for 50 years or more and have a somewhat higher probability of being frayed and popping that courtesy light fuse.

Chris