Hi All,
Another interesting failure mode of the brush system occurred to me
at about 290 hours. I had a tiny (very tiny) oil leak from the hydraulic
hose fittings at the oil pump assembly. (I had replaced the clunky, inaccurate
VDO sensor with a mil-spec transducer mounted on the fire-wall).
The negative direction airflow around the gear box deposited the oil film
on slip ring plate where, mixed with the carbon dust, it shorted out the
rings and failed the controller. The allowed a transient overspeed
condition on takeoff power. Wiping the plate with a rag fixed the condition
and tightening the connectors fixed the leak.
Motto: No good deed goes unpunished
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Ira N224XS
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http://forums.matronics.com/viewtopic.php?p=371284#371284
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