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Reward $ for a triangle stamp on ring gear, for prop install


Apr 13, 2010
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Looking for someone with a first-run Cherokee 140/ 150/ 160 / 180, or Archer 1/ Archer II to provide a high quality photo of the ring gear.

When new, Piper ink-stamped a triangle on the ring gear to aid the assembly line workers while installing the prop. I believe they were ink stamped and not engraved. Lycoming didn't do this, it was done at the Piper factory before the engines were mounted to the airframes.

It should appear on the ring gear, at the 10 o'clock position when facing the engine front. Diagonally opposite from the starter, where you should find the stamped TDC and timing marks that line up with the dot on the starter nose.

The ink-stamped triangle mark would be obliterated when the engine is overhauled, so it's unlikely to be found on anything that's been overhauled.

This is for a bit of assembly line history. Attached is an old photo from a Lycoming operator's manual. In the center you will see what looks like the triangle mark inside a circle. I need a much better photo of an actual flywheel mark.

Will pay $25 by Paypal to first person submitting a high-quality photo of a Piper flywheel with the factory triangle mark on it!

Thanks to anyone who can help!


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