What was found
CREW REPORTED, AFTER LEVELING AT 4000 FT, IN CRUISE CONFIGURATION, POWER WAS REDUCED TO 26" OF MANIFOLD PRESSURE. LT ENGINE WENT TO TO 26" OF MANIFOLD PRESSURE, BUT RT ENGINE REMAINED AT 29". CREW ELECTED TO DIVERT, WHERE AN EMERGENCY WAS DECLARED. LANDING WAS UNEVENTFUL. MX R & R BROKEN MANIFOLD PRESSURE INDICATOR LINE. ACFT RETURNED TO SERVICE.