70aquasport
New member
-2020 Mercury 60 EFI 'Seapro'
Hey all,
So I finally thought I found the source of a recurrent oil/gas/lube slick that happens around my lower unit every time I lower it into the water (whether engine is running or not). I found by slowly lowering the engine in small increments that it seems to start slicking into the water once the area around the shift shaft/driveshaft seals are submerged. With the side cowlings off, you can get a pretty clear view of where the water meets the area where the two shafts/the seals are submerged; and that little portion is definitely where the fluid is coming from:
It's a bit hard to explain on the picture, but it is very clear in person that the fluid, whatever it is, is coming from down near those seals, or at least in the same 'pocket' of that lower unit area, and then up into the water around the lower unit. So, knowing that, I did a full shift shaft and driveshaft seal replacement, but low and behold, the problem is still happening...now I'm stumped.
What else could be down there that is leaking from that same section? Theoretically I suppose it could be unburnt fuel since the exhaust meets in that same area as well? Or motor oil dripping down the crankcase and into the driveshaft housing and down to the lower unit? It's not anything that would be 'outside' of the driveshaft housing, because with the lower cowling off I can see that there's nothing dripping on the outside. So I'm a bit stumped...
I would honestly be happy to offer someone a Venmo bonus if they can figure this out at this point!
Hey all,
So I finally thought I found the source of a recurrent oil/gas/lube slick that happens around my lower unit every time I lower it into the water (whether engine is running or not). I found by slowly lowering the engine in small increments that it seems to start slicking into the water once the area around the shift shaft/driveshaft seals are submerged. With the side cowlings off, you can get a pretty clear view of where the water meets the area where the two shafts/the seals are submerged; and that little portion is definitely where the fluid is coming from:
It's a bit hard to explain on the picture, but it is very clear in person that the fluid, whatever it is, is coming from down near those seals, or at least in the same 'pocket' of that lower unit area, and then up into the water around the lower unit. So, knowing that, I did a full shift shaft and driveshaft seal replacement, but low and behold, the problem is still happening...now I'm stumped.
What else could be down there that is leaking from that same section? Theoretically I suppose it could be unburnt fuel since the exhaust meets in that same area as well? Or motor oil dripping down the crankcase and into the driveshaft housing and down to the lower unit? It's not anything that would be 'outside' of the driveshaft housing, because with the lower cowling off I can see that there's nothing dripping on the outside. So I'm a bit stumped...
I would honestly be happy to offer someone a Venmo bonus if they can figure this out at this point!