The problem/ reason is,
Alpha 1 gen 1 required annual ujoint and gimbal bearing greasing along with the splined shaft.
Alpha 1 gen 2 went to non servicable ujoints and gimbal bearing. Also a grease fitting on coupler to grease shaft which by the way very few ever do, both boat owner or service shop. Many of the coupler grease fittings cannot be reached.
Very bad design.
So many who get a boat dont understand which they have and or are unaware of the differences and what needs to be done.
I pull all outdrives regardless of generation and check everything and grease what needs to be.
Right- you probably remember the 4.3 liter run-on problems of the late-'90s, then. I went to the Regal Boats dealer meeting in '98 and Mercruiser was in damage control mode, with their service bulletin that included:
Use cooler spark plugs
Use a cooler thermostat
Use higher octane gas
Enrich the fuel mixture (IIRC)
Retard the timing
Let the engine cool down before shutting it off
Leave it in gear when the engine is shut off
Install the idle stop solenoid
Total BandAid. Then, they were also having problems with the water seals on the water circulation pumps leaking because the ones that were installed weren't meant to be used with water as the coolant, only Glycol-based coolants. Every time they mentioned a different issue, we all said "Aw, man!".
We then went to the Volvo-Penta presentation and everything got "Now, THAT'S cool!".
I recently worked on a boat for a former employer and he 'did the maintenance'. His brother is a Ford-trained mechanic and my old boss has worked on cars for over 50 years but he neglected every grease fitting. The end cover on the heat exchanger came out and he overheated the poop out of it, which killed his bellows and he had me replace those, along with the trim sender/switch. I replaced the bellows before finding that the gimbal bearing was bad and the puller I was using didn't get it out, so he had someone else do that. I ALWAYS make sure the bellows are snug, sealed and check them with a flashlight to ensure they won't leak but this year, he contacted me to say that he had water coming into the bilge through the hole next to the water fitting, which means water is getting into the bellows with the yoke, telling me that it was my fault, even though three pairs of hands were in there after I replaced the bellows.
Maintenance CAN'T be ignored or avoided.