Headsup for spark plug lead issue

[erich weaver]

Something to be aware of: Twice in the last year I have had to replace one of the leads between my pmags and my automotive sparkplugs. In both cases, the very small band that is attached to the metal retention clip that attaches to the sparkplug tip had broken. This piece is what causes the retention clip to produce an audible pop when it latches onto the sparkplug tip and prevents it from working its way loose. You cant see that its broken by looking into the rubber boot on the sparkplug lead; the retention clip has to be removed from the rubber boot, at which time the broken band falls out in two very small pieces.

Next time you have the cowl off, check the sparkplug lead connections. If you do not hear a distinctive pop when you push the rubber boot down onto the sparkplug, you do not have a good connection and will likely soon see signs of trouble, like elevated EGT and lowered CHT relative to normal on that cylinder. Also, you wont see an EGT increase on that cylinder during the runup mag check for the pmag with the bad lead.

regards,

Erich

[flyingriki]

Did you make your own leads?
Source of the materials?

[erich weaver]

When I originally got my pmags, they provided the materials for the leads and you fabricated them yourself . These days I understand they provide them pre-made and when one of mine went bad I threw money at it and just ordered a whole new set ($75 I think). If you have a little slack to play with, its possible re-use your old lead if you get the nice pmag people to send you a new retention clip that you can crimp on. Maybe there is some place else to buy just the clips, don't know; maybe someone else can chime in with this info.