Ignition lead repair

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Getonit

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i was removing my Mags for the 500 service and I accidentally broke off one of the leads inside the mags. Is it possible to just repair one lead? Or are the economics that bad? Engine is IO-550
 
what type of mag ,make, model, age , photo. how do you brake a lead off? only thing I can think of is the capacitor lead bolt pulled out of a slick mag,due to over tight or locktite.they mean 12 inch lbs.however it is part of a overhall cost anyway. you sure you should be doing this type of work?
 
Single ignition leads can be replaced. Depending on how old the whole harness is, and what kind of condition it is in, it might be worth considering a full replacement.
 
Yes, they can be repaired. It's not that unusual a situation. I have Slick ignition harnesses and had something similar. There's a tool that is needed to install the end of lead into the wire properly if that is what has separated. The replaceable cigarette wire ends just thread on to that.
 
First of all I will have a mechanic reinstall and retime everything, this is njot a complete hangar fairy operation. During removal of mag from housing I caught the end of contactor on cap and pulled it off from ignition wire. Upon closer examination it looks like it just pushes on there, with a small brad looking connector, not sure how reliable that repair wouild be. The leads have about 750 hours on them, and I found two cuts, wear marks through and into the wire shielding. Engine was running fine, no random misses, etc. What is expected life of a harness?
 

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I coat mine with a thin layer of dielectric grease; i too have found those adhered to the housing. Heat + a bit of moisure seems to bond them over time.
 
Getonit said:
First of all I will have a mechanic reinstall and retime everything, this is njot a complete hangar fairy operation. During removal of mag from housing I caught the end of contactor on cap and pulled it off from ignition wire. Upon closer examination it looks like it just pushes on there, with a small brad looking connector, not sure how reliable that repair wouild be. The leads have about 750 hours on them, and I found two cuts, wear marks through and into the wire shielding. Engine was running fine, no random misses, etc. What is expected life of a harness?
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As I mentioned above it is repairable. Find someone who rebuilds/services magnetos; they usually have the tool needed to re-insert it dead center into the end of the lead. You can try to do it yourself and it'll most likely make contact and work, but it is difficult to get it centered, which is what you really want. You do not want to keep poking it in over and over though.

Heat + vibration, and physical chafing kill ignition harnesses. Some installations will go right through a 2000 hour TBO from overhaul to the next. I got 1300 hours from new out of one side of my Aztec and changed the other the next annual - heat had started to breakdown the insulator between the center lead and the shield.
 
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Looks like an updated design similar to my old Slicks. My 50 y/o slick harnesses just press back together, unless the dielectric insulation on the ignition lead is split (mine can be trimmed back and re-assembled). Inspect the insulation, and if no other damage is present, I think you can just reassemble and fly it (I'm not reading your manual right now, so I might be wrong).
 
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