Volvo MS25S Saildrive

[Gypsy]

My boat has a Volvo D2-55 with MS25S saildrive with about 1100hrs on the clock. I recently found water had entered the gearbox and the oil emulsified. As I could not haul her out immediately I pumped out as much oil as I could (a bit more than half of capacity) filled with fresh oil, ran the GB in drive for about 10mins then repeated the process. Since then I have used the GB for about 7hrs but have no further evidence of water ingress. Oil had been checked OK previously about 10hrs before the water contamination was seen.

The boat is hauled out and I have arranged to have the two propshaft seals replaced before next summer.

Has anyone had a similar experience? What could explain this one-time entry of water? How often should one expect to replace the propshaft seals?
Tks


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[andyorr]

At the Southampton BS I asked about SD seals. The guy from ?????? (forgotton which boat stand) said about every 7 years.

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[steve_cronin]

Are you sure he wasn't talking about the saildrive seal? Gypsy was asking about the shaft seals which are a different thing.

You're quite right, most manufacturers and VP themselves recommend 7 years to replace the leg seal or boot. The driveshaft seals have no particular replacement regeme. They operate on the "if it ain't broke, don't fix it" principle but whenever a major overhaul is contemplated, should be replaced following dismantling or whenever there is evidence of water ingress. When this is done is more likely to be hours run based - and that is for the BOAT not just the engine. This is because, to avoid cog & selector fork damage, SDs are left to freewheel when sailing.

Steve Cronin



<hr width=100% size=1>The above is, like any other post here, only a personal opinion

 

[branko]

I have same motor and Sail drive. After 3 years in water ( 8000 Nm) I do not see any emulsion. Oil is clean and as it was. In Volvo service advise to change semerings every 3 years. I have it as spare parts but I shell wait for changing.

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[Gypsy]

You are right Steve, I was referring to the shaft seals. I agree on the ain't broke don't fix it rule. As to the "boat" miles that may be the case for fixed blade props but VP manual says to put the gearbox into reverse when sailing with a folding prop which is what I have. It will be interesting to see if there is visible damage to the seals when they come out.
Tks for your input.

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[Gypsy]

Tks Branko - as I have now had 3 seasons in the water perhaps my time is up. What is curious is that it seems to have been a one-time entry of water not permanent ingress. Anyway, the seals will be changed and we may see some cause when they are inspected.
Tks

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[branko]

Check also prop ( if it is Aluminium).I have found deep scratches where wings are welded to body ( galvanic corrosion).

<hr width=100% size=1>skipp