Aluminum Fan Blade Issue

[chudm71]

I have placed a new aluminum fan blade on. I have tightened the nut and placed the cotter key in. I ran the engine on a 10 mile test drive. I had to tightened the nut again. I was wondering if I should put a washer behind the nut to put it at the correct alignment for the cotter pin. I would appreciate any help.
Thanks.

 

[colin1928]

Yes I put a stainless washer there

 

[Brentwood Bob]

A thin ss flat washer will help prevent the nut from eroding the face of the aluminum casting.

 

[chudm71]

Okay thanks Guys..