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I have some interesting informatio, and also need to apologize to the list. I seriously questioned the Continental engine manual published torque values of the prop hub nut on tapered shaft engines as being way too high at 200 - 225 ft lbs., as the group had been experiencing several failed hubs..... The Ercoupe manual calls for 100 foot lbs., and I thought for sure that the new figures were too high, possibly causing the hubs to fail from the tremendous pressures exerted as the hub was forced onto the tapered shaft. The older Continental manual gives the proper installation as: tighten with a bar, and give it a couple of whacks with a brass hammer, to tighten it satisfactorly. That is the practice I have been following since learning to do so in the USAF in the 1950's. I have often wondered what amount of torque was produced by this method, but certainly not 225 ft lbs, I thought. Recently John Wright removed the hub from my engine, requiring over 300+ ft lbs to remove it !!! WOW. Was I surprised and embarrassed. Here I had been preaching that the new figures were too high, only to find I had been using 150% of the new figures, and 300% of the older Ercoupe figures! I apologize to the group for potentially misleading you. Excess tightening will cause the hub to fail as it is forced up the tapered shaft.....and loosing a prop in not a good thing. I endorse the use of a special torque wrench to attain the new published firgures ...and now see the folly in using a bar and hammer, which can lead to too loose or too tight fitting hubs and possible failure. Fly Safe - Have Fun Regards, Harry Francis Blacksburg, VA. N-93530 ========================================================================== ==== To leave this forum go to: http://ercoupers.com/lists.htm
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