Heat Shrink Tubing protects encased wires from damage Options

[JeffBowlsby]

The heat shrink tubing used on our cars' engine bay wiring collects and routes individual wires for convenience, protects the wires from physical abrasion, dirt and fluid contamination, and most importantly heat exposure. The internal wires have a thin wire insulation further protecting the concealed copper wires and preventing internal shorts, as long as the wires remain pliable and the insulation does not crack.

One consequence of heat if it gets too high, is that it can melt, even char the outer Polyolefin HST casing, within limits. I recently repaired Ted Piersons (TRP) original FI harness that was charred in certain locations and was delighted that the damage was limited to the outer casing and did not reach the internal wires which generally requires a replacement harness. If the outer casing is damaged, hardened, cracked, even charred, its time to replace it to save the internal wiring. Consider it a preventive maintenance item. Automotive engine bay wiring harnesses are not capable of being 'life of car' equipment, they are a maintenance replacement item. Replace damaged casing and other worn out or damaged components such as the rubber boots and wire terminals, and you will greatly extend the service life of the harness.

Heat exposure is arguably the most damaging exposure and common Polyolefin HST protects against heat up to about 195 degF. Higher performing HST is available rated to almost 400 degF, but its generally overkill for 914s.

[TRP]

The heat shrink tubing used on our cars' engine bay wiring collects and routes individual wires for convenience, protects the wires from physical abrasion, dirt and fluid contamination, and most importantly heat exposure....

... I recently repaired Ted Piersons (TRP) original FI harness that was charred in certain locations and was delighted that the damage was limited to the outer casing and did not reach the internal wires which generally requires a replacement harness.

True story! The shrink tubing did its job quite well. When I sent the harness to Jeff it was clearly 'brown' and stiff in a few areas where it had been exposed to some high temps over the years; luckily the wires inside were in great shape! There were a few areas where the heat shrink had been cut back or compromised, the wires in those areas needed to be replaced. The newly repaired harnesses from Jeff are perfect.

Thanks Jeff for tuning up my harnesses! They look SPECTACULAR.

Ted