Part 40 Re-Fitting the Propeller Gearbox ...

Introduction ...

This page contains photos of the process of re-fitting the propeller gearbox housing assembly to a ROTAX 912ULS engine (built August 2006). This page does not cover the disassembly of the propeller gearbox or reassembly just the refitting. Disassembly, inspection and reassembly may be covered in another technical insight page.



ROTAX 912ULS Re-Fitting The Propeller Gearbox

Image 1

Having ensured that the propeller gearbox is free of FOD make a start by cleaning the mating face of the gearbox. Remove all traces of previous flange sealant. And then thoroughly degrease the mating face so that there is a sound surface for the new application of flange sealant to adhere to ...

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ROTAX 912ULS Re-Fitting The Propeller Gearbox

Image 2

Do the same to the rear of gearbox housing / extended crankcase ...

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ROTAX 912ULS Re-Fitting The Propeller Gearbox

Image 3

The bolts this gearbox was previously secured with showed signs of corrosion so the owner of this engine has elected to fit a new set of M6 and M8 bolts and washers. These are the set of 8 x M6 bolts ...

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ROTAX 912ULS Re-Fitting The Propeller Gearbox

Image 4

These are the set of 2 x M8 lower bolts ...

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ROTAX 912ULS Re-Fitting The Propeller Gearbox

Image 5

Degrease the bolts and apply a small dot of the appropriate Loctite (Please see the IPC / Heavy Maintenance Manual for details) to the end of the bolts ...

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ROTAX 912ULS Re-Fitting The Propeller Gearbox

Image 6

Having applied a uniform coat of flange sealant to the gearbox mating face (Apologies - I omitted to take a photo of this step!) and then offer up the gearbox to the rear gearbox housing and push the gearbox home. It may just slide on - usually you have to mesh the small gear on the crankshaft with the large gear of the gearbox gearset by rotating the propeller flange back and forth vey slight until they mesh. Torque the eight M6 bolts and two M8 bolts up to their target torque (Please see the IPC / Heavy Maintenance Manual for details).

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ROTAX 912ULS Re-Fitting The Propeller Gearbox

Image 9

The gearbox is now ready to have the mechanical fuel pump refitted ...

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