Shifting Issues - Merc Alpha 1 Stern Drive

[blamtro]

I have a 1978 SeaRay 207. 350 GM V8. Drive is a reman Alpha 1 gen 1. Everything runs great except boat will fail to shift into reverse, but only when the boat is moving forward such as maneuvering to get into a dock slip, using reverse to slow forward momentum, ect. It seems to only be when the movement of the boat in the water is moving the prop. My shift/throttle lever and cables seem smooth with no binding but I am stumped. When going forward, in gear, at idle, boat will smoothly shift from forward to neutral to reverse and so on with no issue. However when you take it up a step such as to overcome a current or wind and need a little more; this is when problems arrise. When shifting quickly from forward to neutral to reverse, the lever moves smoothly but it never actually shifts into reverse, just reving of the engine when the lever moves backwards.

I've pulled the drive off, everything seems to be in order. I can very easily move the shift lever on the drive and the prop locks in the appropriate directions, ect.

I don't want to just tear into the shift cable without some further advice, but that's what all my googlefu has been able to come up with.

 

[Bt Doctur]

Did you try adjusting reverse according to the manual and the adjustable stud?

 

[Rick Stephens]

Did you try adjusting reverse according to the manual and the adjustable stud?

+ on Bt Doc's post. Increase the linkage throw by moving the lower shift cable end pin up a bit in its slot.

 

[blamtro]

I have not, I will adjust once I get the drive back on the boat. Another item of note, the shift shaft that goes in the drive itself has quite a bit of up and down play. There is some lateral play but not as much. Is this normal?

 

[achris]

... the shift shaft that goes in the drive itself has quite a bit of up and down play. ...

Check that the rubber and stainless steel washers on top of the lower shift shaft are in place.

 

[blamtro]

I do not have the vertically oriented shift plate, this has the old style horizontal shift plate. does that make a difference?

+ on Bt Doc's post. Increase the linkage throw by moving the lower shift cable end pin up a bit in its slot.

 

[blamtro]

Thank you for the help. A followup on my solution. The shift cable was corroded and needed to replaced. While I was in there I had to tap the bell housing to use the new gen 2 cables. Replaced gimbal, bellows, and all related parts. Once all back together, still wouldn't shift properly. Got to looking and the shift shaft on the bell housing was not fully engaging the lower bronze shift shaft on the drive. In fact, it was just barely touching; so little that there was enough friction to shift into forward but not enough to put it into reverse. Apparently, whenever the drive was reassembled, the corrrect washer was not put in place to hold the bronze shift foot in place. I simply wrapped a piece of split fuel hose around the bronze shift foot to hold it up at the proper height and secured it with a ziptie until I have time to split the drive. Shifts perfectly now.

 

[Rick Stephens]

Yup, needs the right set of washers. Good find on the lower cable. Sure is nice feeling to have it all perfect again.