63 Merc 500, Cant shift to reverse anymore.

PlayDoh

Seaman Apprentice
Joined
Jul 5, 2006
Messages
35
First off, thanks for looking and any help you can provide.

My Motor (50hp) had a bad impeller when I got it, and I tossed in a new one and she runs fine now. My problem is I can't get the lower leg to go into reverse ever since I took it apart. More specifically, the first time I put it in the water after working on it, it went in to reverse, and it did it one other time months later when I jammed it hard.

There are these two little round 'cam lobes' that the shifter rod goes threw the center of. These 'cam lobes' fit together, but when rotated they push away from each other, or vice versa. Now when the lower leg was removed, these fell to the ground so I couldn't mark their initial position.

That ended up being a major pain, since it took me a week to get the lower leg to go back together properly. So these lobes fit together, but the top half/lobe, remains stationary and fits into the leg like a sprocket, and you need to put it in the right position, or the lobes will cause the leg not to fit.

So I had to take the lower leg off, pull out the top lobe and move it one tooth over, leaving the lower one on the leg, and shove it up and try it again. Last year, I took the leg off again thinking since it felt close to going into gear, it was probably just a tooth or two off, but it only seems to fit one way.

The throttle will rev with the lever in reverse, and the gear shift shaft does turn. The close up picture shows the gear shift shaft, which is highlighted with read broken lines.

I had to ask for help here while trying to get the lower leg in, and I got a few comments how it should be in reverse when the leg goes on, and I've tried both gears, but it seems as long as the motor and leg are in the same gear when it gets put together it doesn't matter.

Actually, to be more specific again, I can't seem to get the lower leg back on unless its in one position only. I know its something I did, and the 'cam lobes' are the only thing I can think of. Nothing was broken, bent or missing when I put the leg together.

Thanks again. I'll take some pics of the 'cam lobes' and the removed leg next time I take it off.
 

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