Auxiliary Tools - Rotax MMH-912 Series Maintenance Manual

10.4) Auxiliary tools

– compression tester or 2 pressure gauges with calibrated orifice, adapter for
dial gauge in spark plug thread
– valve spring mounting pliers
– step punch for valve guide
– adjustable reamer 6.5 to 7.5 mm (0.256 to 0.295 in.)
– valve seat machining device, valve lapping paste,
– gearbox support plate
– stud extraction tool
– scraper, very fine emery cloth, grinding tool, cover sheet, adhesive tape
– cleaning agent, approved cleaners, funnel, graphite marker.
– magnetic particle tester DEUTROFLUX, series UHW, or equivalent.
See 72-00-00 sec. 5.1.1.
These testers are suitable for complete combined magnetic particle crack
inspection of all ferromagnetic materials. For this purpose an A.C. field
circulation can be combined with a shifted phase A.C. circulation . The
two magnetizing methods are independent from each other and can be
applied separately.
To achieve the direction changes of the magnetic field vector necessary for
indication of cracks in any direction, the alternating currents serving as the
current supply for the different methods of magnetizing are dephased by
120° to each other:
a) current circulation for indication of longitudinal cracks
b) field circulation for indication of transverse cracks
c) auxiliary circulation for indication of axial and radial cracks on parts with bores
right through by using an electric auxiliary conductor (copper bar).
Measure tangential field intensity with field intensity tester Deutrometer 3870
or with an equivalent field intensity tester. The target value is 10 - 50 A/cm.
If cracks are detected then the affected part must be replaced. Clean and
demagnetize the part. The maximum remaining magnetism must not exceed
1.2 A/cm.
The inner bore of the propeller shaft is excluded from magnetic particle crack
inspection.
■ CAUTION:
Effectivity 912/914 Series
Edition 1 / Rev. 3
BRP-Powertrain
Maintenance Manual
Observe the manufacturers instructions.
00-00-00
page 39
October 01/2010