76-23-03 R1: Exhaust System

76-23-03 R1 BELLANCA: Amendment 39-2772, as amended by Amendment 39-5454. Applies to BellancaMN Models 17-30, serials 30-139 thru 30-262, 17-30A, serials 30-263 and up, 17-31, serials 32-1 thru 32-14, and 17-31A, serials 32-15 and up, airplanes certificated in all categories. For airplanes with 200 or more hours time in service on the effective date of this AD, compliance is required within the next 10 hours time in service and thereafter at intervals not to exceed 100 hours time in service or the next annual inspection, whichever occurs first. For airplanes with less than 200 hours time in service on the effective date of this AD compliance is required before the accumulation of 210 hours time in service and thereafter at intervals not to exceed 100 hours time in service or the next annual inspection, whichever occurs first. To prevent exhaust system failures which could result in cabin air contamination and heat damage to components in the nacelle accomplish the following: (A) Visually inspect the muffler and tailpipe assemblies for cracks paying particular attention to the ball joint welds, the outlets of the muffler and resonator, and the support for the tailpipe assembly. (B) Inspect the exhaust system for freedom of movement at the ball joints by removing the tailpipe support bolts. When the bolts are removed: (1) The left tailpipe assembly must drop from its supported position unassisted. (2) The right tailpipe assembly must move from its supported position when a two pound force is applied one inch below the resonator can 90 degrees to the axis of the resonator, i.e., the assembly must move when a two pound pull is applied one inch below the resonator can forward and down. (3) If a greater forces than the above are required: (a) Disassemble the ball joint and inspect for surface abnormalities such as galling or wear marks. (b) Rework the ball joints as required to correct noted discrepancies.(c) Reassemble the ball joint. Do not overtighten the clamp as this may distort ball surfaces. (4) Repeat (B)(1) thru (B)(3) as required until compliance with (B)(1) and (B)(2) is demonstrated. Amendment 39-2772 became effective November 23, 1976. This amendment, 39-5454, becomes effective November 7, 1986.