Bracket Air filter element PN and spark plug recomendation

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8359
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Joined: Tue Nov 27, 2018 10:53 pm
Name: Tamer A
Location: KSNA
Aircraft Type: 1946 C120 O-290-D
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Re: Bracket Air filter element PN and spark plug recomendation

Post by 8359 »

Speaking of rotating, Any special sequence? Or just top to bottom and bottom to top? (On the same cylinder).
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6643
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Name: John C
Location: KLCI, NH
Aircraft Type: 1946 C140/C90
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Re: Bracket Air filter element PN and spark plug recomendation

Post by 6643 »

Magneto systems fire half the plugs by making the center electrode positive and the other half negative. You want to reverse the polarity (to even out the electrode wear) and move the plug from top to bottom, or vice-versa.

If you have a plug rack, take them out and put them in the rack like this:

Top .... - 1 2 3 4
Bottom - 1 2 3 4

Next, swap 2 with 3 and 1 with 4 in each row, then install the ones from the top row in the bottom and the bottom row in the top, so, 1 top goes to 4 bottom, 2 top to 3 bottom, etc.
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