Mercury alternator belt

[Cablebandit]

this post is just to consolidate info. You can go to an auto parts place with one of these numbers and get a belt for the alternator. I have a 240 efi

4k315
4pk812
4pk817

 

[AnviL Man]

Wish I saw this post sooner. I spent almost $80 on a replacement belt for my 240 EFI. Question though, what are the differences between those 3 you have listed?

 

[UKGlenn]

4 is the amount of grooves pk is code for the shape of the grooves and the 812 is belt length in millimetres. Because of the belt tensioner you can get away with few millimetres here or there.