The International Cessna^® 170 Association

During my annual I found that the protrusions on the spinner base plate had cut three to four inch grooves about 1/16 inch deep into the prop. I have dressed the area down and re-painted with prop paint. I did some grinding on the base plate to improve the clearance, now I am ready to re-mount the prop.

Question is how much torque is to be used on a eight bolt prop on and 0-300 engine?

Torque Prop bolts to 250 in-lbs for 8-bolt props, and 55-65 FT-lbs for 6-bolt props on C145/O300 engines. (Fig. 14-1, pg. 14-3 of the Cessna Service Manual, 100 Series, 1962 and prior.)

And you're a certified repair facility for props and have accomplished the repair according to the manufacturers maintenance and repair manual?

It sounds to me like 1/16" deep grooves in that area of the prop could well render it non repairable. Fly safe.