[jwilkey84]

I cannot find the proper impellor for a 1975 40hp model number 40555C. I can find them for older models and newer ones, but not for this one.

[cougar1985]

go to your local evinrude johnson dealer and ask for part number 0386165

[cougar1985]

checked brp site and for 74 75 76 same part number and proably for many other years also.

[BoatBuoy]

For some reason, that impeller is a dealer-only(JohnnyRude) item. The aftermarket dealers won't have it. That's why you can't find it. The only online source I know for dealer-only parts is ishopmarine.com.

[F_R]

378891, 775521, 386165, 18-3006 are all the same thing. They just use different drive keys.