AD/LYC/86 Amdt 2 - Propeller Governor Oil Line (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES

Lycoming Piston Engines

AD/LYC/86 Amdt 2

Propeller Governor Oil Line 11/98

Applicability: All Lycoming four cylinder engines with a rear mounted propeller governor and external oil line.

Requirement: 1. Rigid Oil Line Installation:

1. Inspect the propeller governor external oil line for evidence of leaks, cracks, abrasion and correct fitment of support clamps. Replace as necessary.

b. Replace the propeller governor external oil line, if fitted with aluminium attachment nuts, with an oil line having P/N AN818-6 steel attachment nuts.

c. Replace aluminium propeller governor oil line elbow P/N MS20822-6D with a steel elbow P/N MS20822-6.

2. Flexible Oil Line Installation. If a flexible governor oil hose is fitted, inspect the hose and ascertain the specification of the hose. If not of TSO C53a - Type D specification, replace with correct hose in accordance with Lycoming Service Instruction No.1435, Supplement 1.

Note: FAA AD 90-04-06 and Lycoming SB 488A refer.

Compliance: Unless previously accomplished:

1. Engines in service: Within 25 hours in service. Uninstalled engines: Prior to installation in an aircraft. 2. Engines in service: Within 25 hours time in service. Uninstalled engines: Prior to installation in an aircraft. This amendment becomes effective on 8 October 1998.

Background: Several applicable Lycoming engine installations in Australia have been found with TSO C53a -Type C flexible governor lines fitted and there have been a number of premature failures of these lines. This directive has been amended to include inspection for fitment of the correct specification flexible hoses installed as an alternate to rigid lines and the removal of those flexible hoses which do not meet the manufacturer's installation requirements. The operating parameters of the installation is such that Lycoming has determined that TSO C53a-Type C hoses are not an acceptable substitute for rigid lines and that only TSO C53a-Type D hoses will suffice.