How to Repair the Electrical Sheathing on a Wire

Engine vibration can damage your wiring harness insulation.

Engine vibration wears on engine wiring harnesses. The constant movement and abrasive points can wear a hole in the harness and wire insulation. You can repair the damage as long as the copper strands in the wire are not damaged. If you find damaged copper strands, do not attempt to repair the wire, but replace the complete wire. A good fix for damaged insulation is to use adhesive lined heat-shrink tubing. The tubing will shrink around the installation and bond to the wire with the adhesive providing a watertight seal. If you do not have heat-shrink tubing and need to repair a wire, try this repair using RTV and black electrical tape.

Things You'll Need

• Dow 744 RTV sealant or equivalent
• Black electrical tape
• Wrench, 10mm

Instructions

1. Disconnect the battery. Use a 10mm wrench to disconnect the negative battery cable.

2. Locate the damaged wire. Spread the RTV sealant into the damaged insulation. Wait 30 minutes for the RTV sealant to cure.

3. Wrap black electrical tape around the sealant and damaged area. Tightly wrap the electrical tape over the sealant and damaged area until it covers both sides by one inch.

4. Reconnect the negative battery cable to the negative battery terminal.

Tips & Warnings

• This is only a temporary repair. Permanently replace the wire at the first opportunity.

References

• Autoshop 101: Wire, Terminal and Connector Repair
• Ohm Check: How To Fix a Wire
• Ellsworth Adhesives: Dow Corning Sealant 744 RTV