Small play in Pre Alpha Gimbal to spline shaft

[bowbender6]

First post, been reading for a while. I have a 1973 Starcraft Islander with a rotten transom so I am tearing everything apart and going over things. I believe it is a Pre Alpha outdrive (no gimbal trim sensor, just trim limit at the top of gimbal Ring). I never noticed when driving the boat but there is a small amount of play between the splined shaft and the gimbal ring. The splined shaft is split and a plug goes up through the bottom of the shaft. Is that what is used to take out the play. I tightened it up a little but didn't want to go to far until I figured out if this plug opened up the split split shaft and tightened thigs up. I have several manuals and diagrams but hey weren't real clear on this matter
Thanks

 

[achris]

.... I believe it is a Pre Alpha outdrive (no gimbal trim sensor, just trim limit at the top of gimbal Ring)....

Incorrect, you have a Mercruiser-1 drive (MC1 for short).

... The splined shaft is split and a plug goes up through the bottom of the shaft. Is that what is used to take out the play.

No. That plug is to protect the threads in the bottom of the shaft. The threads are for a slide hammer to screw in when removing the shaft.

I tightened it up a little but didn't want to go to far until I figured out if this plug opened up the split split shaft and tightened thigs up. I have several manuals and diagrams but hey weren't real clear on this matter
Thanks

The shaft and gimbal ring wear on those splines, and that's why Merc changed to a square shaft in the 80's. Unfortunately there is no easy way to rectify your problem short of removing the gimbal housing and replacing it with a later model (like an Alpha One), but that would involve so many other things that need to be changed.

 

[bowbender6]

Thanks.
That's exactly the info I needed. I didn't think there was a fix without redoing the gimbal.