Mercruiser Alpha One - Lower Shift Shaft broke

[jerryjerry05]

Re: Mercruiser Alpha One - Lower Shift Shaft broke

Lots of assuming going on here!!!!! That part is EASY to replace.Get a factory manual.Then follow instructions.
Mounts go bad all the time and don't mean rotten transoms or stringers.J

 

[haulnazz15]

Re: Mercruiser Alpha One - Lower Shift Shaft broke

Hope you plan on replacing the those rusted out u-joints. Looks like it had a bellows leak, so the gimbal bearing will need to be replaced as well. Since you have to separate the drive upper and lower anyway, I'd put in a new water pump/impeller while you're there. Chances are it needs it.

 

[jtybt]

Re: Mercruiser Alpha One - Lower Shift Shaft broke

That piece you have in your hand is bronze and not easily broken. Likely the person who last tried to mount the drive didn't know what they were doing and forced the drive with the lower shift shaft in the wrong position.

You should be able to pull what's left of the shift lever. It is hollow and internally splined to fit over the lower shift shaft. You may have to split the upper/lower case.

What about the rotten wood inside of the boat. That is the critical part.

 

[JustJason]

Re: Mercruiser Alpha One - Lower Shift Shaft broke

Interesting... I've seen those things nearly bent in half... but I haven't seen a broken one like you got.

Either way... Haulnazz is on to something. You need bellows and u joints at the very least. Water did get up in there so your probably going to need a gimbal bearing as well. On top of that, the main input shaft seal is only a single, 1 way seal. They do not use back to back seals up there. If you had water in the bellows there is a good chance you have water in the drive unit.
Take out the 4 bolts on the top cap and have a look inside the drive. If the gears and bearings are all rusty up there, then you need to be planning on buying an entire drive unit from SEI.

Trust me on this... before you go through all the trouble. Grab a small drill bit, like 3/16ths or something. From the inside of the boat drill 1 inch into the transom on a couple of different spots. Preferably down low. If you get anything other than clean dry sawdust then you have a weak transom at best, a rotten boat at worst. If the front mount was rotted, and you have a rusted up input shaft, and everything I just mentioned... trust me, your looking at thousands to repair here.

To answer your question directly... Split the drive unit in 2 and that broken shaft will fall through. You'll see how to get a new one in once you have it apart.