1972 40hp mercury no reverse shifting out of sync after water pump install

[dkonrai]

i installed a new water pump and now i dont have reverse. there is a small cam on the shifter at the lower unit i dont think i installed this correct.
motor starts but no reverse
thanks
dino

[ledgefinder]

Yeah, it's not on right. Take it back off, shift the LU into neutral, then orient the cam so that the line/junction between the ramped and flat parts of the cam points directly forward (i.e., towards what would be the front of the motor/bow of the boat). Then put the LU back on.

[r.hebert]

i also had that problem but

mine is a 88 45 and is going forward when i put in reverse and backwards when i put in forward think its the same problem?

[dkonrai]

Yeah, it's not on right. Take it back off, shift the LU into neutral, then orient the cam so that the line/junction between the ramped and flat parts of the cam points directly forward (i.e., towards what would be the front of the motor/bow of the boat). Then put the LU back on.

should it be facing this way?


or this way?


then put the lu in neutral?

[dkonrai]

sorry or this way?

[dkonrai]

i finally got this thing together. why would anyone engineer a spring loaded shift??

[strcrftoregon]

Im getting ready to put mine together....which way was correct in your pictures? To the front or back. Thanks

[72Harris]

Having same issue --- could someone reply to which picture is correct? Seems like when I pulled the LU, the cam had the ramp up against the water pump. But tried many times to rotate the cam different degrees, but always in forward. Is there any other way to line this up to the shift cable easily? Thanks in advance for any help!!

[lazzlonewolf]

where is the other half of the cam? That black piece looks like it but the cams look broke off it? I have a '73 40hp merc. And what spring are you talking about? in the shifter itself?

[lazzlonewolf]

you still need the top half of the cam. pull that black piece off and look at the sides it looks broken? you need the top half of that cam before it will go in reverse again.

[72Harris]

Do you have a pic of the top half of the cam you speak of? When I pulled the lower unit, the black part shown in the pictures was the only piece there. I do plan to change the part as the part had shown wear at the top of "ramp". This '72 motor has a shift cable spline that slides over the shaft above the black reverse cam part (at least what I cam calling it). Then I can see a spring loaded pin in the upper unit that must be pushed up by the ramp of the cam. However, as you can see by the pics that someone else provided - the shaft has about 6 splines the shift cable can slide over, but unfortunately -- could not find the correct location. I looked at how the shift cable behaved, and it only rotates a very short distance. In the pictures that were part of this thread, it appears the ramp of the cam is metal -- whereas my part is one solid piece of hard plastic. The dealer can get me a new part. Perplexed why Mercury did not put 'dots' or alignment marks on these parts. Any ideas? Should I expect an "2nd part" of the cam when I order a new one? Thx yet again!