What was found
RUDDER BOOST ENGAGED WHEN POWER WAS ADVANCED ABOVE 85 PERCENT. CHECKED SYSTEM, FOUND RIGHT FIREWALL SHUT-OFF VALVE OPERATED NORMALLY UNTIL APPLYING APPROXIMATELY 30 PSI SHOP AIR. THEN VALVE WOULD CLOSE, INDICATING ENGINE FAILURE.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
RUDDER BOOST ENGAGED WHEN POWER WAS ADVANCED ABOVE 85 PERCENT. CHECKED SYSTEM, FOUND RIGHT FIREWALL SHUT-OFF VALVE OPERATED NORMALLY UNTIL APPLYING APPROXIMATELY 30 PSI SHOP AIR. THEN VALVE WOULD CLOSE, INDICATING ENGINE FAILURE.