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Old 01-08-2018, 08:23 AM
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Flypast111
 
Join Date: Dec 2009
Location: Cincinnati, OH
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Wink BE-1265 Break-In Completed - Results

OK - I have completed the break-in by performing the following;
a) cleaned and reassembled back cover plate (backplate) - noticed some 0.002-0.005 in. wear in backplate from crankshaft rod/pin assembly (could be the result of repeated applied pressure to spinner/crankshaft via electric starter usage)
b) used 5x3 nylon prop and "short" glowplug (reduces internal cylinder compression)
c) reset NVA to 2 turns open for start => then reduce to 1.5-1.75 turns open for run; using 5x3 nylon prop - engine ran mostly stable and consumed full 2oz tank (YEAH!)
d) changed prop to 6x3 wood & repeated above procedure (c) - engine ran well for 1oz and then required needle valve adjustment to retain HI rpm (it seams that large props and associated reduced engine rpm limit fuel draw (suction @ venturi) after the fuel level decreases below the NVA - working against gravity)

Conclusion - the engine will now run a full 2oz tank on a 5x3 nylon prop - it suffers from low suction at the NVA - it likes lower compression and HI rpm ... plus HI levels of nitromethane ... for stable engine operation (stable rpm) - Cheers, Flypast111