1969 Merc 500 50hp shift shaft help!

[dandy]

I just replaced the water pump on a merc 500 I just bought from a private party. I was fortunate that the lower unit came off easily, however, it appears someone had tried fixing the pump before and had a rough go of it...one lock nut missing, one stud stripped and the gaskets were installed in the wrong order. Fortunately I have a service manual and put it all back together correctly (with a new pump and re died stud). The problem I have is I removed the bushing from the top of the shift shaft to clean it and must have turned the shaft in the process. I'm not sure what position the shaft should be in now. I'm pretty sure I can align the bushing by checking the location of the matching bushing on the mid unit but the shaft itself turns about 200 degrees. It's in forward gear as the prop ratchets clockwise (resistance counterclockwise) - this is the position I put the lever in when I started this project but where should the shift shaft be set when I reinstall the bushing - all the way clockwise, cc, or centered. Again once I know what position to rotate the shaft to I can align the bushing. Thanks for any help.

 

[Merc805]

Re: 1969 Merc 500 50hp shift shaft help!

I would turn the shift shaft coming out of the L/U til it's in neutral. Prop will turn freely both ways with no "click" Then change the controller and upper shift shaft to neutral and re-assemble them. if your motor is tilted up the hooks will be engaged, so after assembly you will need to select forward to put it back down.

 

[dandy]

Re: 1969 Merc 500 50hp shift shaft help!

The problem I'm having is the shift shaft rotates about 180 degrees (freely) and the prop exhibits the forward gear characteristic - ratchets clockwise, resistance cc over the full 180 degrees. How do I get the shift shaft to a neutral or reverse position as it seems to stop at each end of the rotation? I don't want to force it past either end unless I know I can. Thanks

 

[mellowyellow]

Re: 1969 Merc 500 50hp shift shaft help!

I always kept it in forward when removing lower unit... <br />have someone move the flywheel by hand a<br />little bit to align the splines if it won't just<br />slide back up.

 

[dandy]

Re: 1969 Merc 500 50hp shift shaft help!

This still doesn't answer my fundamental question. It was in forward when I removed the lower unit and I haven't changed that. I need to know what position the shift shaft should be in when I put the bushing back on as I can easily rotate the shaft about 180 degrees with my fingers while its in the forward gear position. I can install the bushing in the correct place to meet up with the mid section but this is possible with the shift shaft in several positions over the 180 degree rotation range (not sure how many splines). Thanks

 

[dandy]

Re: 1969 Merc 500 50hp shift shaft help!

Any additional suggestions? I'm heading home to try my luck at reinstalling the lower unit. Thanks

 

[natedennis]

Re: 1969 Merc 500 50hp shift shaft help!

this sound similar to a problem im having the 1964 merc 200 im rebuilding,, except my lower unit is still stuck on. the gears were changing fine before i try to get the lower unit off, but i had a little trouble,, oiled and tapped, and the thing dropped down a inch. at that point stuck and the gears stopped working even if i completely reattach it.

 

[mellowyellow]

Re: 1969 Merc 500 50hp shift shaft help!

if u "max" advance into forward, u should be good.