Propeller bolt torque for
McCauley fixed pitch metal propellers, only

Disclaimer: I have no professional or expert qualifications of any kind.
It's fully up to you to check any information you find here with
standard aviation industry sources such as aircraft maintenance
manuals, flying instruction books and, above all, FAA regulations!

For this, it is critical you Google McCauley Service Bulletin SB227B.  You can find it in seconds.

Be sure to read the cautions about wet versus dry torque.  The fixed pitch torque table is for DRY torque.

Fred Wellman sent this:

I located McCauley SB227B which states:

The installation torque for McCauley fixed pitch propellers is determined by the bolt diameter.

Bolt or Nut Torque (DRY)

Diameter          Pound-Feet            Pound-Inches
3/8               30 to 25              360 to 300
7/16              45 to 40              540 to 480
1/2               65 to 55              780 to 660

I had "eyeballed" the bolts and guessed they were 9/16.  They are in actuality 3/8 which would require the 25-30 ft. pound torque.