AD 2012-10-13 supercedes earlier guidance on replacing starter adapters on certain TSIO engines...
FAA has issued Airworthiness Directive (AD) 2012-10-13, affecting A36TCs and B36TCs with TSIO-520UB engines, as well as other factory turbocharged airplanes. This AD supercedes AD 2011-25-51.
The new AD expands the types of engines and starter adapter part numbers affected by the AD. FAA is issuing this AD to prevent starter adapter gear shaft failure which could cause oil scavange pump failure and inflight engine shutdown.
For full details, read:
AD 2012-10-13 http://bonanza.org/images/pdf/2012-10-13.pdf
Continental Motors Mandatory Service Bulletin 11-4B http://bonanza.org/images/pdf/msb11-4b.pdf