Hi,
Yep, I know what you’re talking about.
I had to run new wires for my wing tip strobes through a Comanche wing which only has two inspection holes. I ended up using long flexible wire routing poles that did not follow the nav light routing.
Some mechanics have been able to use the nav light wiring as a pull wire after connecting the new wiring but I decided that that could create problems, especially is the pull wire and the new wires separated somewhere in the wing that was inaccessible. If that happened I would have two problems instead of one.
I removed the wing tip and the inspection panels I had to work with, decided that since I was going to the trouble of running wires to add an additional 22 gauge wire (not used for the current project) to the wires I needed to run, then fished through the holes for the wires.
Since I couldn’t install rubber grommets due to lack of access, I protected the wires with a sleeve of Ico-Flex XPF (or Protect-Fast) sleeving. (https://www.aircraftspruce.com/catalog/elpages/expandablesleeving.php), Spirap and caterpillar grommet when I could.
I believe you can get access to the wiring by removing your fuel tanks. If you haven’t inspected for wing spar corrosion behind the tanks (Piper Service Bulletin 1006) in the last 7 years, as recommended in the service bulletin you may get better access and check for corrosion by combining the two tasks.
I have attached the bulletin.
Let me know what solution you use.
Steve
