On Thu, 26 Jan 2006 13:03:16 -0600, "Jim Burns"
wrote:

Replacement Ignition Harnesses...
Who's replaced them?

Me.

Reason(s)?

You name it. old-and-trashed, oil soaked and deteriorated, burnt,
abraded by water, corroded hardware, chafed, pinched, cut..primarily
because I allegedly got paid to do it.
..
Engine Make/Model?

Pick one. 4-to-1 Lyc-to-TCM

Airplane Make/Model?

Every "modern" Piper except a TCM Malibu, lotsa Cessna/Beech singles,
couple of Barons.

Straight or 90 degree?

Both, depended on the install.

Standard or all weather?

Both, depended on the install. Don't recall ever "converting" one from
standard to all weather.

Best or worst brands or manufacturers?

Standard Unison/Slick harnesses are inexpensive and relatively easy to
repair, you can usually shorten them a couple times before poking in a
replacement lead. The silicone coating will gradually abrade and get a
little funky looking. Downside is they don't like the heat, and unless
they've changed the plug nut from the aluminium I'm familiar with, the
nuts will gall if you try to force them onto a boogered or corroded
sparkplug. Poking on a new nut on is fairly simple.

Have also used Bendix/TCM harnesses. They are pretty much mandatory on
turbo installs (w/90 degree elbows) depending on the wire routing so
you can keep them away from the exhaust stacks. They hold up a lot
longer, are a little tougher to repair/poke in a new lead. Cad-plated
steel nuts won't gall on funky plugs.

Custom features or wire sizes?

Didn't have any real need for them.

On our Aztec's we always used the standard Unison harness with
straight (all weather) ends, secured the lowers to the intake pipes,
uppers to baffle bolts extending through the head to the "inside" with
plain nuts/lock washers. We used the Unison's 'cause when (not if,
when) an exhaust gasket blew or a stack dropped and semi-torched the
lead they were easy and cheap to replace.

Really doesn't make a big difference whose leads you use if you are
careful routing and securing them.

TC