I have a 1984 Larson with a 3.0L mercruiser engine. I have been battling a problem for almost 1 year now where my boat will shift into forward, but not reverse. If I tune the cable, I can get it to go into reverse but not forward. The other posts that I put on here over a year ago everyone was saying to get a new lower shift cable. Here is what I have found since then.
- The slop in the lower shift cable is within Merc Specs so I do not think the lower shift cable needs to be replaced.
- I have adjusted the cable following the manual about 15 times now thinking I am missing a step but I have done it enough to know I have now and I am on the brink of insanity.
I am not sure what control box I have on the boat, maybe by the picture you guys can tell me.
Here is what I found out last night, this might get confusing but stick with me.
-I hook the shift cable up to the engine and measuring 6" from center hole to center barrel.
-I then adjust the control cable to line up with the shift plate hole, give it 4 turns forward and install it.
- I then move the shifter from forward to neutral, and back to forward and it is fine.
-I then shift the lever from forward, to neutral, then to reverse. The prop clicks but does not lock.
- I then shift from reverse to neutral, then to forward. Sometimes it locks, and sometimes it does not. When I shift it back to forward from reverse and measure center hole to center barrel, it will be something like 6.5". So the shift cable is not being pulled back to 6" position like it should be.
Here is why I am thinking the shifter is the issue, but it is expensive to buy if it is not so I need some help.
If I disconnect the control cable from the engine plate (leaving the other end hooked up to the shifter) and I put the shifter in the forward idle position, I then go back to the engine and push on the control cable end and it moves in and out anywhere from 1/4-1/2". It does the same if the shifter is in neutral, or reverse. I would think that if the shifter is in forward, or reverse, it should not have any play in the cable when pushing back and forth at the engine end. I got a flash light and looked at the back of the shifter and if I push back and forth on the plate that the cable mounts to I can move it back and forth about 1/4"-1/2" while it is shifted into gear. The red arrow in this picture shows where I have my cable mounted and, and that is the plate that has movement in it.
Then if I disconnect the control cable from the shifter, and install it back on the engine plate with the lower shift cable mounted, I push in on the control cable end at the shifter side, and there is no play at all. So I don't think the slop / play is in the cable, but in the shifter box.
So my main question is, are these shifters supposed to have movement in this plate when it is in gear, or is this where my slop is messing things up?
- The slop in the lower shift cable is within Merc Specs so I do not think the lower shift cable needs to be replaced.
- I have adjusted the cable following the manual about 15 times now thinking I am missing a step but I have done it enough to know I have now and I am on the brink of insanity.
I am not sure what control box I have on the boat, maybe by the picture you guys can tell me.
Here is what I found out last night, this might get confusing but stick with me.
-I hook the shift cable up to the engine and measuring 6" from center hole to center barrel.
-I then adjust the control cable to line up with the shift plate hole, give it 4 turns forward and install it.
- I then move the shifter from forward to neutral, and back to forward and it is fine.
-I then shift the lever from forward, to neutral, then to reverse. The prop clicks but does not lock.
- I then shift from reverse to neutral, then to forward. Sometimes it locks, and sometimes it does not. When I shift it back to forward from reverse and measure center hole to center barrel, it will be something like 6.5". So the shift cable is not being pulled back to 6" position like it should be.
Here is why I am thinking the shifter is the issue, but it is expensive to buy if it is not so I need some help.
If I disconnect the control cable from the engine plate (leaving the other end hooked up to the shifter) and I put the shifter in the forward idle position, I then go back to the engine and push on the control cable end and it moves in and out anywhere from 1/4-1/2". It does the same if the shifter is in neutral, or reverse. I would think that if the shifter is in forward, or reverse, it should not have any play in the cable when pushing back and forth at the engine end. I got a flash light and looked at the back of the shifter and if I push back and forth on the plate that the cable mounts to I can move it back and forth about 1/4"-1/2" while it is shifted into gear. The red arrow in this picture shows where I have my cable mounted and, and that is the plate that has movement in it.

Then if I disconnect the control cable from the shifter, and install it back on the engine plate with the lower shift cable mounted, I push in on the control cable end at the shifter side, and there is no play at all. So I don't think the slop / play is in the cable, but in the shifter box.
So my main question is, are these shifters supposed to have movement in this plate when it is in gear, or is this where my slop is messing things up?
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