Torque 912 ULS

Hi Sean,

The task "Installation of the Propeller Gearbox" is found in the Maintenance Manual - Line. In the current version of the manual (Ed.4, Rev.1) it starts from page 11 of Chapter 05-50-00.

As noted in the procedure, the torque setting of the M6 screws is 10 Nm.

10nm = 90 in/lbs. (88.5 in/lbs slightly rounded off) The two 8mm are 18 ft/lbs. = 25nm (24.4 nm slightly rounded off)

Sean...go to your maintenance manual heavy.  Find the gearbox section and at the beginning of that subject there will be an illustration.  This will show each fastener and if it requires lube or Loctite if needed.  Each will show the torque called out by Rotax.  If there is nothing noted, as there is in some fasteners in the engine, then use the generic value for the thread size and pitch.  This is found in the general section near the beginning of the MMH. 

Cheers

As of Edition 2 of the 912/194 MMH, the procedures to remove and reinstall the propeller gearbox were deleted from the MMH and replaced with notes to refer to the MML for removal and installation instructions.

Also removed in Edition 2 was the list of standard torques.

Figue 8.3 in the new MMH is a useful aide memoire, but before I use any value shown in an illustration I always like to check the actual procedure to make sure it matches. More than once when referencing various technical manuals I've found discrepancies between illustrations and the corresponding text.

Hi Tim

The process of moving things is to try to remove double statements.  Multiple locations for data such as torque values makes it very difficult to update any changes that occur.  Because of that they are working to remove any repeated text and have it in only one location.  

In regards to the gearbox some time ago they moved the R&R info to the MML.  Training under iRMT would show R&R in the Maintenance level training class, removal and replacement of components.  Repair of these components is found in the MMH, you would require the additional training to disassemble the component (gearbox in this case) in the Heavy maintenance level training.  

The past  5 years all torque values are being shown in the descriptive page just before a group of tasks for each major component in the MMH.  The line by line torque values will be deleted so that there will be only one location for torque shown in the end.  In the general section of the MMH is the secteion showing standard torque valve for the metric fasteners.  This however should not be used until you are sure that the fastener in that specific location is not required to be used with lower or higher values or with Loctite.  This is shown in the discriptive page in the MMH for that engine type.  

Cheers