Service difficulty report · Mount · Mooney M20TN

Difficulty date
May 31, 2012
Submitted
May 31, 2012
Operation
General aviation
Aircraft
N963JM
Make and model
Mooney M20TN
Aircraft serial
310024
Aircraft time
944 hours, 550 cycles
Engine
Cont TSIO550G
Engine time
944 hours, 550 cycles
Propeller
Hartzl PHCJ3YF1
Part
Mount
Part number
590030501
Condition
Mismanufactured
Location
Engine
Part time
944 hours
Stage of operation
IN
How discovered
V
Nature of condition
W
Precautionary procedure
K

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

DISCOVERED ALL 4 ENGINE ISOLATOR MOUNT BOLTS LOOSE DURING A 100 HOUR INSPECTION. NOTED THAT THE ISOLATOR MOUNT BOLTS DO NOT HAVE A SAFETY WIRE OR LOCKING PROVISION. FOUND SEVERAL AREAS OF CHAFING RELATED TO THE ENGINE NOT SECURED TO ENGINE BED MOUNT. REMOVED ALL ENGINE ISOLATORS & INSPECTED. FOUND METAL SHAVINGS BETWEEN UPPER & LOWER ISOLATORS. FOUND LT AFT ENGINE MOUNT BRACKET THREAD INSERT PULLED & CROSS THREADED. REPLACED BOTH REAR ENGINE MOUNT BRACKETS WITH NEW. REPLACED FRONT ENGINE ISOLATOR MOUNTS WITH NEW KIT, AND REINSTALLED EXISTING REAR ISOLATOR MOUNTS KIT, IAW IPC AND AMM. FOUND INSTALLING ISOLATOR MOUNTS & BOLTS VERY DIFICULT. ENGINE MOUNT BRACKETS DO NOT ALIGN WITH ENGINE BED MOUNT FOCAL RINGS. WITH ALL ISOLATORS INSTALLED & BOLTS TORQUED ISOLATORS ARE DISPLACED FROM CENTERLINE & ARE LATERALLY LOADED. ISOLATORS DO NOT SEAT ON FULL CIRCUMFERENCE OF FOCAL RING. REMOVED ALL ISOLATOR MOUNTS FOR FURTHER INSPECTION OF BED MOUNT. CONTACTED ACFT MFG ABOUT THE ALIGNMENT ISSUES. MEASURED MOUNT IAW DWG AND FOUND THE ENGINE BED MOUNT FOCAL RING CENTERLINES ARE TOO NARROW BY .2500" ON ALL 4 CORNERS. NO DEFORMITIES OF THE BED MOUNT NOTED.

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