Gap adjust on tempest BY plugs

sansoneservices

sansoneservices

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gary sansone
Tapping the combined brain cells on the forum.. Electronic mags require enlarged plug gaps. I have a tool for enlarging gaps on standard (massive) plugs but the tempest extended nose BY plugs don't facilitate the tool. I could lock needle-nose vise grips on the ground electrode but it leaves marks. I'm going to make a tool since there isn't one available. Any grease monkeys here have an idea?
 
You can buy the expensive pre-gapped plugs made for the Electroair but honestly, I’ve got 3 Surefly mags on my Lycomings and when I swap the plugs, I just use them as is, pre-gapped after checking to make sure they are at normal spec, always seem to be around .018 / .016.

I’ve used a curved pick before and adjustment them out without leaving marks but zero indication of any difference in performance or starting. Once the plugs have 100 hours on them, I just gap them to be about .020/.022 which is close to natural wear at that point and then keep them there.
 
Skymac said:
You can buy the expensive pre-gapped plugs made for the Electroair but honestly, I’ve got 3 Surefly mags on my Lycomings and when I swap the plugs, I just use them as is, pre-gapped after checking to make sure they are at normal spec, always seem to be around .018 / .016.

I’ve used a curved pick before and adjustment them out without leaving marks but zero indication of any difference in performance or starting. Once the plugs have 100 hours on them, I just gap them to be about .020/.022 which is close to natural wear at that point and then keep them there.
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Thanks, I installed new plugs as recommended by SureFly and didn't open the gaps. Normally gaps widen with age as you stated. I might just leave mine in place but a friend wants me to install a SureFly mag and enlarge his plug gaps.
 
sansoneservices said:
Tapping the combined brain cells on the forum.. Electronic mags require enlarged plug gaps. I have a tool for enlarging gaps on standard (massive) plugs but the tempest extended nose BY plugs don't facilitate the tool. I could lock needle-nose vise grips on the ground electrode but it leaves marks. I'm going to make a tool since there isn't one available. Any grease monkeys here have an idea?
Click to expand...

Gap Setting Tool CT-415AV - Champion Aerospace

www.championaerospace.com www.championaerospace.com

There are some clones available, but you'd need to be sure that they come with both adapters like the Champion unit does.

1732385677412.png
 
sansoneservices said:
Thanks for the reply but I have that tool, it doesn't widen plug gap, only closes the gap. I need to open the gaps to .025 - .035 for electronic ignition
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I made a tiny wrench for that. Dunno if I can find it. Being retired, stuff like that settles to the bottom of my toolbox drawers. It was just a piece of 1/8" x 3/4" flat bar, maybe two inches long, with a notch cut into one side near one end. Leave maybe 1/8" between the end of the notch and the end of the bar, enough to be stout but enough to avoid ANY contact with the center electrode or ceramic. Kind of like a tiny pipe wrench. The width of the notch should be hardly any more than the thickness of the electrode, and deep enough to accommodate width of the electrode. Easy to bend the electrode out a tiny bit.

The plug makers will tell you not to try to widen that gap. They're afraid you'll put side force on the center electrode and crack the ceramic insulator, which will result in spark shorting to ground and possibly pieces of that terribly hard ceramic breaking off and scoring the cylinder and piston very deeply.
 
Dan Thomas said:
I made a tiny wrench for that. Dunno if I can find it. Being retired, stuff like that settles to the bottom of my toolbox drawers. It was just a piece of 1/8" x 3/4" flat bar, maybe two inches long, with a notch cut into one side near one end. Leave maybe 1/8" between the end of the notch and the end of the bar, enough to be stout but enough to avoid ANY contact with the center electrode or ceramic. Kind of like a tiny pipe wrench. The width of the notch should be hardly any more than the thickness of the electrode, and deep enough to accommodate width of the electrode. Easy to bend the electrode out a tiny bit.

The plug makers will tell you not to try to widen that gap. They're afraid you'll put side force on the center electrode and crack the ceramic insulator, which will result in spark shorting to ground and possibly pieces of that terribly hard ceramic breaking off and scoring the cylinder and piston very deeply.
Click to expand...
Thanks for this ^^^ I imagined a tool as you described. I have a steel 3/8" open end, will cut off one end and slice/notch in it matching your description
 
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