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  #11  
Old 10-15-2019, 08:22 PM
propjoe propjoe is offline
 
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Is this Hoffman propeller counter weighted?
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  #12  
Old 10-31-2019, 02:00 PM
Boyd Birchler Boyd Birchler is offline
 
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I had a aerobatic 3 blade Hoffmann that had similar problems. The counterweights were in the wrong position.
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  #13  
Old 10-31-2019, 02:16 PM
DaveO DaveO is offline
 
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Trying to turn the blade by hand, why not take out spark plugs to turn prop to work on spinner. Should be easy then.
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  #14  
Old 10-31-2019, 06:05 PM
scsmith scsmith is offline
 
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Quote:
Originally Posted by Boyd Birchler View Post
I had a aerobatic 3 blade Hoffmann that had similar problems. The counterweights were in the wrong position.
If it is a non-aerobatic prop, then I agree, sounds like course pitch stops. If it is counterweighted, this sounds like a likely culprit.

FWIW, I can not change the pitch on my Whirl Wind prop by twisting by hand either, even after almost 600 hrs.
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  #15  
Old 05-22-2020, 06:41 AM
Boyd Birchler Boyd Birchler is offline
 
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I had a 3 blade Hoffmann on a 540 powered Christen Eagle. The prop was an aerobatic prop with counter weights in each blade root. The blades on counter weighted props can be easily rotated by hand.

It did pretty much as you described because the counter weights were positioned incorrectly.

The counter weights are easily repositionable. Mine were off 80 degrees.

If your prop is not counter weighted; this is all meaningless.

Last edited by Boyd Birchler : 05-22-2020 at 06:56 AM.
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  #16  
Old 05-22-2020, 07:36 AM
Taltruda Taltruda is offline
 
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Quote:
Originally Posted by DaveO View Post
Trying to turn the blade by hand, why not take out spark plugs to turn prop to work on spinner. Should be easy then.
They arenít talking about turning over the engine, they are talking about twisting the blades From fine to coarse to check the spinner cutouts.
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  #17  
Old 05-23-2020, 01:21 PM
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n82rb n82rb is offline
 
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Use air pressure
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