1988 Merc 5.7L Mag - Alpha One Lower/Upper Drive shaft seals

[Fastrack]

Hey.

I bought a new SEI Lower Unit for my Alpha One. All was great until I hit a rock at low speed. Well they've fixed it and it's on the way back to me (replaced some bearings, gears, prop shaft & the case).

When I removed the lower I noticed some diluted oil on the vertical drive shaft (where the splines are). I saw this last year before I purchased the SEI lower so it's not related.

The oil had no water it in when drained, so water isn't getting in, but oil is getting out

So I suspect it's the "Upper Seal" #11 - 32511 in the diagram, Or could it be simple as the "Lower Seal" #10 - 965031? I understand to replace the Upper Seal I need to remove the upper gear set (I have the spanner wrench & Service Manual).

So I guess if I venture down that road, I should replace the horizontal oil seals too?

I see there's a Seirra Kit (18-2648 - same as 26-32511A1) and it includes both seals in question as well as the horizontal oil seal as well as o-rings for the upper.

There is No Oil in the Bellows so the horizontal seal is fine. (No rust either)

Ben

 

[Bt Doctur]

Depending on the seal use National 712250 for the inputshaft.
remove the inputshaft, remove the vert shaft, old driveshaft seal drive from inside out,old oil seal drive from outside in To install . oil seal from inside down, driveshaft seal from outside in(flush with housing)