As far a dirty fuel goes, I try to always pour my fuel through a 'Mr Funnel' That will even filter out water supposedly. I'm almost always refueling at home out of fuel cans. JImChuk
https://www.amazon.com/s/?ie=UTF8&ke...l_7iaccrm5ei_e
Line Maintenance Manual
The above link is to the line maintenance manual. Chapter 5 goes through the prop strike procedure. It refers to the "heavy maintenance manual" for the procedure of the inspection.
Heavy Maintenance Manual
The heavy maintenance manual (link above), chapter 72, section 3.9 give the step by step procedure.
California Power sells the crankshaft distortion measuring tool for about $250-$300 .Most common dial indicators with appropriate fittings can be used to measure crankshaft runout Rotax has adequate instructions for use of the distortion tool.
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