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Crankshaft question

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taildraggerpilot

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I have a certified Pitts S2A with an AEIO-360A1E and recently decided to overhaul the engine. After tearing it down and inventorying the parts, I discovered (according to the parts manual) the wrong crank and rods were installed at the previous overhaul.
The removed crank is p/n: LW-17179 and the rods are p/n: LW-13422. These are meant for high horse high rpm engines and would be ideal for a hopped up experimental.

The previous overhauler (engine OH'd in 1990) insisted the rods were original and the acro crank is what lycoming sent them to install. I called lycoming and they won't give me a copy of the factory build sheet. Guidance from the FSDO says I need to go by the parts catalog even though parts catalogs are not FAA approved. No field approval either, even with 1300 hrs of successful operation.

During a discussion with the previous overhauler, he indicated he would not reinstall the crank and rods in today's regulatory environment without some sort of documentation trail. I might be out of luck on this one...

Per SB 465, I'm supposed to have a 17176 or 13B27128 crank.

Question, other than buying a new crank and rods, does anyone know or have info on whether this crank/rod combo might be legal? I hate to see a standard crank go to waste.

Thanks in advance.
Ben
 
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