Alpha One Gen 2 Outdrive Mystery

[Mark R.]

Boat sat in storage for months last year, and then one day, gear lube just started leaking out the water inlet grate.
I thought that meant the vertical driveshaft double seal had failed, so I replaced it and all the other upper unit seals, along with a Speedi sleeve on the yoke surface, and a new gimble bearing.
I did not mess with the lower half at all, because it had passed the pressure test.
I reassembled everything and at that point, the entire outdrive passed the pressure test.
So I launched the boat, and it ran GREAT.! I parked it on my dock lift, up out of the water, and didn’t touch it for a month (we went on a long international trip).
A week after we got home, it all of a sudden puked out gear lube again.(!), leaking out through the water intake grooves again.
What in the world could possibly be causing that to happen..?!?
BOTH times, the boat was totally fine just sitting for a long period of time, and then without even being touched, it just all of a sudden started leaking.!
REALLY scratching my head over this one…
I have not had a chance yet to haul it out and pull the outdrive again.
Just wondering if anyone has any ideas about what could possibly be happening here…

 

[alldodge]

Is a weird one but with lube coming out water intake holes I would look at the water pump housing

 

[Bondo]

Is a weird one but with lube coming out water intake holes I would look at the water pump housing

Ayuh,..... Or the shift shaft seal,....

 

[Pmt133]

My shift shaft seal "passed" a pressure test until you simulated shifting, then it started to leak.... very slowly. Definitely worth checking both of those.

 

[JonBoat55]

All oil seals need to be under pressure and have shift/shaft motion at the same time to pass. These leaks can be sneaky

 

[Mark R.]

Is a weird one but with lube coming out water intake holes I would look at the water pump housing

Yes. Probably a good suggestion. So items 19, 20, and 21 in this diagram.?
Still can't imagine what would suddenly cause them to just start leaking...!
Boat sat perfectly fine for over a month. Everything bone dry. No leaking.
And without even being touched, just started leaking.! It's done that TWICE now.!
.

 

[Pmt133]

Is it starting leaking, or is it enough time sitting for the slow leak to finally come out of the inlet....

 

[Mark R.]

My shift shaft seal "passed" a pressure test until you simulated shifting, then it started to leak.... very slowly. Definitely worth checking both of those.

OK. I will replace them too. So items 36 and 37 in this diagram.?
.

 

[Pmt133]

OK. I will replace them too. So items 36 and 37 in this diagram.?
.

Gen 2 is a little different... it should be a whole housing. I think its the whole cluser of 34-37

 

[Mark R.]

Is it starting leaking, or is it enough time sitting for the slow leak to finally come out of the inlet....

No. Both times, once it started leaking, it ran out in a pretty noticeable stream.
I'm certain it went from no leak to significant leak. Kind of like it just burped it out...

 

[Bondo]

Yes. Probably a good suggestion. So items 19, 20, and 21 in this diagram.?
Still can't imagine what would suddenly cause them to just start leaking...!
Boat sat perfectly fine for over a month. Everything bone dry. No leaking.
And without even being touched, just started leaking.! It's done that TWICE now.!
.

Ayuh,..... As with 'bout anything mechanical, it works perfectly,...
til it don't,...

 

[Mark R.]

Ayuh,..... As with 'bout anything mechanical, it works perfectly,...
til it don't,...

Yes, I know, but that usually occurs while we are using it, or right after we use it.
This happened (twice now) without it being touched, after sitting perfectly fine for over a month.

I'm beginning to suspect it has something to do with temperature...
Both times it happened during the middle of summer with some pretty hot days.
I wonder if the heat is pressurizing the gear lube and then it finds the weak seal.
But shouldn't the vented cap on the reservoir prevent pressure from building up.?
I wonder if I have a combination of a suspect seal, AND a bad (clogged?) reservoir cap..?
.