1957 mark 55

[PP7636]

Hi all, I was doing some maintenance on my lower unit and decided it was time for a replacement prop shaft, so I ordered one, however it was way too long. 12 3/8” roughly, for the 55 that would be correct so I’m assuming someone swapped lower units on this engine sometime before I owned it, here’s the kicker, I have no clue what prop shaft I need, at first I thought maybe a mark 30 but those are only 8” and the one I pulled out was 9 3/8”, anyone know what I’m looking for? Splines match the mark 55 shaft. Any info would be greatly appreciated

 

[racerone]

Post a picture of your lower unit / the parts and the prop.

 

[timguy]

Size photos at 1000k or smaller each. Where are you getting your parts? Maybe they sent you the wrong one.

 

[fitz73222]

Hi all, I was doing some maintenance on my lower unit and decided it was time for a replacement prop shaft, so I ordered one, however it was way too long. 12 3/8” roughly, for the 55 that would be correct so I’m assuming someone swapped lower units on this engine sometime before I owned it, here’s the kicker, I have no clue what prop shaft I need, at first I thought maybe a mark 30 but those are only 8” and the one I pulled out was 9 3/8”, anyone know what I’m looking for? Splines match the mark 55 shaft. Any info would be greatly appreciated

Wrong forum johnsoldmercurysite.com