Alpha one Gen 2 SEI 116. upper 1.42 ratio possible failure

[@kodiak536kodiak536]

I think you're correct. There shouldn't be that much play in that shaft. I'm no marine mechanic but, mechanically drive shafts should have "limited" lash/play when "properly" installed. Don't know what the actual tolerances are so, I can only suggest you contact SEI support and ask. I have a SE116 myself, came with my boat that was bought used 3 years ago with no issues until decently. Found a crack near the prop end going up the exhaust and all the bellows dry rotted and fell apart, causing boat to take on water REALLY FAST! Got a brand new lower just yesterday to replace it, haven't open the box yet. When I do later today, I will comment back and let you know what I find from this brand new OEM lower drive unit.

[@hildablanco1591]

Your stainless steel propeller is the couse of the problem in gear wear it is to heavy on the shaft especially when shifting or getting air born go aluminium 3 blade pontoon prop

[@brettsummer5070]

For curiosity sake. There's only 1 bearing down there(standard pressed on the shaft with a race that's down there on the housing). The top cap you removed obviously let's the shaft become loose. With only the horizonal gears keeping you from pulling it all the way out. It's possible the gear mesh wasn't right, the preload set on the large double bearing (not shown in video) needs to be exactly right as well.

[@chasebecker6054]

That bearing definitely looked worn, I bet the other one was worn too and the gears had some play, doesn't take much, causing your noise because there was a bigger gap/misalignment! Those things go through tremendous rotational force! Think of the energy it takes you to swim as fast as you can! Michael Phelps is fast trains every day and doesn't come close to plane! Putting a load on sloppy gears like that and noise gets worse! Probably made you feel sick in your stomach! I'm glad you were able to get it fixed before it mangled the gears! I have the feeling this is kinda one of those units you just put in forward gear leave it there don't shift it often do not go past idling everywhere and it will last. Everywhere I read and everyone I talk to makes them sound pretty weak. I know there.. pretty good, but I understand the reputation. My dad's had one of these alpha 1 gen 2's let go.. it was on a 454 why I do not know.. It definitely can not handle that kind of power. you need a bravo 1 or bravo 2 maybe something even stronger.. Get your wallet out maybe the next one will live after a conversion. He didnt want to go through that. I was young but I don't remember a warning. Just striped gear motor wouldn't crank. That made him quit boats and really left a bad taste in his mouth. I have a 3.0 4 cyl in my boat and the gen 2 alpha one is a match only at half its load. To be honest I don't think it's a very good drive for most of the boats they've put it on.. I think the rating is 150 horse. IF THAT! Most of the time i'm so easy on it half throttle cruise no pulling always trying to not take so many people never tow anyone. Hopefully I get luckier than you for a lot longer. If my gen 2 starts making noise I'll stop it quick after seeing this video! I definitely see a need for a shower as well I should install one of those

[@kevinbastedo3004]

What oil are you running? I recommend amsoil

[@phillipcothern3864]

I want to let everyone know that though I could not figure out at first where the noise was coming from I eventually replaced the upper unit and all is good now. SO my lower unit was fine and this upper unit was definitely failed.

[@roberthinze2425]

I bet there’s a bearing below that bottom gear that broke. I had an omc stern drive with the same issue

[@0987mulder]

i have a sei 116 ratio 1.50. this makes so much noise that the radio has to do louder. I don't recommend anyone to buy this outdrive.