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Six-Cylinder PMag Plug Wire Map?

Ironflight

VAF Moderator / Line Boy
Mentor
I’m running the spark plug wires for my IO-540 that will sport two six-cylinder P-Mags, and rather than randomly throwing wires in various places, or recreating what some one else has already done, I’d see if someone has already mapped which wire in the kit goes where. There are six plug wires for each mag - one short, one long, two equal medium-short ones, and two equal medium-long ones. Two P-Mags, twelve leads, so double those numbers.

The question is which is intended to go where? Obviously, Emagair knows, since they cut the lengths….but I couldn’t find it in the manual! I could be staring right at it of course, but anyone else already done this homework?
 
I’m running the spark plug wires for my IO-540 that will sport two six-cylinder P-Mags, and rather than randomly throwing wires in various places, or recreating what some one else has already done, I’d see if someone has already mapped which wire in the kit goes where. There are six plug wires for each mag - one short, one long, two equal medium-short ones, and two equal medium-long ones. Two P-Mags, twelve leads, so double those numbers.

The question is which is intended to go where? Obviously, Emagair knows, since they cut the lengths….but I couldn’t find it in the manual! I could be staring right at it of course, but anyone else already done this homework?
AFAIK they have never marked which lead goes where.
What I’d do is split the leads into 2 sets of short, medium, long. Use 1 set for each mag.
L Mag - select lead lengths needed for cyl 2, 4, 6 (top plugs) & 1,3,5 (bottom plugs) & repeat for R Mag.
Btw I’d measure & note the lengths of each lead for the future when doing the resistance test for serviceability. HTH
Ps - I also use a label (black on white cloth tape) to mark which bank of coil is 1&2 and 3&4 (ie for 4cyl, not sure how they are done on the 6cyl) on the side of the mag as the aft side can be hard to read.
 
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OK, so I decided to do the homework….12 wires, 12 positions, how hard can “hunt and peck” be? A little careful guessing and the lengths all come out pretty close when draped over their respective cylinder location. So ‘ll share the data for anyone lookign in the future. Note that I describe the as-supplied leads as “short”, Short-medium”, “long-medium”, and “long” becasue I didn;t measure the actual lengths before installing…..lazy….

Six Cylinder P-Mag Plug Wiring.jpeg

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I'm more of a visual person, this is what I did and just taped them to the side of the plane when running the wires. I decided to run top plugs from one P-Mag and bottoms from the other instead of each mag doing both. According the the manual, either way is acceptable. I'll clean these up these diagrams for my wiring manual.

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