Service difficulty report · Lead · Piper PA31350

Difficulty date
March 29, 2000
Submitted
April 27, 2000
Operation
General aviation
Aircraft
N27471
Make and model
Piper PA31350
Aircraft serial
317852018
Engine
Lyc LTIO540J2BD
Part
Lead
Part number
MHB4014
Part serial
4072550
Condition
Separated
Location
Starter
Part time
1,071 hours
Component
Field Brushes · Prestolite
Component part number
MHB12A
Stage of operation
IN
How discovered
V
Nature of condition
O
Precautionary procedure
K

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

What was found

RIGHT ENGINE FAILED TO START. INVESTIGATION REVEALED BOTH FIELD BRUSH LEADS WERE SEPARATED FROM THEIR RESPECTIVE BRUSHES. ONE BRUSH SHOWED NO INDICATION OF ARCING IN THE LEAD ATTACH HOLE IN THE BRUSH, WHILE THE OTHER DID. IT APPEARED ONE BRUSH LEAD SEPARATED AND PLACED THE ENTIRE START LOAD ON THE OTHER BRUSH CAUSING IT TO FAIL AT THE LEAD ATTACH POINT. THE STARTER''S OVERALL CONDITION WAS EXCELLENT. THE INSIDE WAS CLEAN AND BRIGHT. FAILURE APPARENTLY WAS DUE TO A POORLY CONSTRUCTED BRUSH/LEAD ASSY THAT LEAD TO PREMATURE FAILURE. WHEN THE OLD BRUSHES WERE COMPARED TO NEW BRUSHES, THE WEAR WAS NEGLIGIBLE. (X)

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