Slippery Electrical Connections
| 01 October 2002
Do you know how to make it easier to slide electrical connections together or easier to take them apart after they’ve been together for a long time? How about the same questions applied to bayonet bulbs? Sometimes slide-together electrical connections don’t like to slide. Bulb bases are the same way. They don’t like to turn, especially when exposure to moisture has caused corrosion. Isn’t it exasperating to try to change a burned-out bulb only to have it break because it won’t come out of the socket? The older the car, the more likely it is to have these problems, both because of age and the design of the electrical equipment. In particular, first generation Mustangs can benefit a great deal from careful attention to electrical connections.
The trick is to apply a thin film of petroleum jelly to the base of the bulb; i.e., to the contact point(s) on the bottom and to the metal base where it contacts the socket. Slide-together connectors can be handled in a similar fashion. Apply a thin film to the opening(s) on the female side of the connector, just enough to place a thin membrane of petroleum jelly over the hole(s). When the bulb is put in the socket or when the connector is pushed together, the petroleum jelly will provide some lubrication which makes the job easier. It will also provide some corrosion protection and it will make future disassembly much easier. A thin film of petroleum jelly won’t compromise the electrical connection; in fact, by reducing corrosion, the connection is more dependable. On concours cars be careful with your housekeeping; wipe away all traces of excess from connectors that are visible to judges.
If you’re restoring a car, consider applying petroleum jelly to each connection and each bulb base as you go through the assembly process. If you have a driver, think about methodically removing each bulb and disconnecting each connector so they can be cleaned and reassembled with a film of petroleum jelly. You’ll be glad you took the time to do the job at your convenience rather than, for example, waiting until you need to replace a burned-out corroded bulb. Bulbs never burn out at a convenient time, you know. Murphy’s Law says that if a bulb is going to fail, failure will usually occur when it’s most inconvenient, like when it’s time to go through tech inspection at a show. Furthermore, that particular bulb will have the worst corrosion of any bulb on the car.
Petroleum jelly or wheel bearing grease can also be effective in reducing the potential for a floating ground in older Mustangs. All ground connections need to be clean and tight with good bare metal to bare metal contact. During assembly, use a light smear of grease/jelly on the connection to help keep it free of corrosion and help maintain the integrity of the ground. If judging is a consideration, wipe away any excess. While you’re working with grounds, make sure the ground circuit is complete. Most devices use the car’s unibody as the ground path but the negative side of the battery isn’t connected to the body. It’s connected to the engine block. The critical ground-link between the engine and the unibody is a wire that connects the engine to the body at the firewall. Be sure it’s in good condition with tight and clean connections at both ends. Check it closely because it’s prone to failure from heat and engine movement.