Mercury 1957 Mark 55E problem

[sbrown21]

I need some help ? I took apart a mercury 40hp lower unit , it came with a boat I bought , the problem is when I put it on my boat when it  is shifted in forward it runs in reverse and when shifted in reverse it runs forward. The shifter shifts fine so I could live with that but being in reverse it will not go full throttle forward. What have I done wrong , the prop runs counter clockwise in forward and clockwise in reverse. Help !

[dave-bernard]

which control box do you have? call me 1 914 310 7086

[billw]

I would bet that when you had the lower unit off, the shift shaft got so turned around that it’s working the cam follower/plunger from the back side, because the six-splined shift shaft connection is clocked wrong. You are not the first to do this and you won’t be the last. When you take off the lower unit, I forget which way is which on the shift shaft but when you shift it, you should feel a distinct detent in neutral and reverse. If you don’t feel them, try turning the shift shaft through its free arc range and keep going, seeing if you can feel the detents in the other direction.

Long live American manufacturing!

[sbrown21]

billw    I think you are probaly right when I took it apart last fall the shifter shaft fell out I had a very hard time putting it back in and finding and lining up the splines in the lower gear case. I put a oring on the shaft the other one was missing that way it wouldn’t fall back out. I hope i just put the cam and coupling back wrong.   Thanks

Steve Brown

 

PS thanks   dave-bernard also it’s a mercury shifter 57 so I think  that’s not the problem

[billw]

I hadn’t realized that you had the gear case apart. This makes me even more sure that the cam position is the problem. Check the manual to be sure but I believe that most Mercs, with the exception of a few portable one and two cylinder models, have the cam pointing toward the left or port side, when viewed from the rear, with the detents facing you. ( facing the trailing end of the gear case.) If you put the cam back in upside down, then you’d feel the cam detents but they would be on the WRONG side. Again, you are not the first person to have possibly screwed this up.

Long live American manufacturing!

• This reply was modified 3 years, 6 months ago by billw.
• This reply was modified 3 years, 6 months ago by billw.

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