Sail drive leak - options?

peter2407

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Hi - it's more of a weep than a leak, but are there alternatives to lifting the boat out and taking the saildrive out and replace the seals? Thanks as ever.
 
Hi All - it's water (assumed to be sea water but will confirm) into the bilge. Plus the leak alarm (for the detector between the two seals) goes off when the engine is turned on.
 
I would get the seal changed asap
How old is it?
I have a volvo & recommendation is every 7 years. I think insurance co might have something to say of left
I did mine myself & saved a lot of money
Quite easy now i have done it once, but you need someone t o help with lifting
Only regret is i did not change the shaft seals at the same time as they went a year later & it would have been easier on a bench rather than grovelling under the boat
 
Hi All - it's water (assumed to be sea water but will confirm) into the bilge. Plus the leak alarm (for the detector between the two seals) goes off when the engine is turned on.

I didn't know there was a leak alarm. Is that standard on Volvo sail-drives?
 
Agree with the guys above about the seal, but would like to add one thought. There have been failures of the bonding in of the moulded engine bed around the cut out in the hull. This has led to the engine bed filling up with seawater and finding its way out of the bed by any means possible, ie through bolt holes etc. When these engine beds are supplied they need to be cut to shape, are very shiny and may still have mould release wax residue on them. Unless they are thoroughly cleaned and abraded before bonding in (especially in the hull cut out area) even the slightest pin hole will allow seawater to enter the cavity of the bed. Either way, the boat will have to come out to check/change the seal, but check the bed for water ingress. If there's water in there, the bonding has undoubtedly failed somewhere around the aperture.
 
Bearing in mind the huge hole in the hull and what that could lead to, I'm afraid it's time to reach for your wallet with a prolonged drying out and new seal.

There is usually a choice of places to go though, have a look for the cheapest the engineer can get to you; if not doing it yourself.
 
Agree with the guys above about the seal, but would like to add one thought. There have been failures of the bonding in of the moulded engine bed around the cut out in the hull. This has led to the engine bed filling up with seawater and finding its way out of the bed by any means possible, ie through bolt holes etc. When these engine beds are supplied they need to be cut to shape, are very shiny and may still have mould release wax residue on them. Unless they are thoroughly cleaned and abraded before bonding in (especially in the hull cut out area) even the slightest pin hole will allow seawater to enter the cavity of the bed. Either way, the boat will have to come out to check/change the seal, but check the bed for water ingress. If there's water in there, the bonding has undoubtedly failed somewhere around the aperture.

Is that on yanmars, Volvos, or both?
 
What's all this prolonged drying out about? It's a rubber seal. not a gelcoat, that needs replacing. Out one day, fix the next, back in the day after. Routine job for a marine engineer if paying to have it done.

Angus,

by ' prolonged ' I meant - with preparation - a day or two dried out, so a few tides; not a career at it for some marine engineer. :)
 
Just to clarify what Saxon Pirate said:
The beds moulding can have a leak deveop around the aperature cut in the hull.As he says it is shiny when delivered to the builders, so the factory get the job of degreasing and roughing it up so it will bond with the interior of your nice new hull.
Say after a while you encounter tree trunks or branches, the loads on the three point mounting on a saildrive can cause, not the diaphram, but the physical joint between the hull and the engine beds to fail, resulting in water ingress.
To test for this drill holes say 4mm each, near the front of the engine beds.No water should apear, ie the space is hollow, empty except for air.If failure of the joint in the engine beds is anywhere else in the outer periphery of the moulded beds, it does not allow water in but is undesireable in terms of structural integrity.
Replacing a perfectly good diaphram seems a waste of time, but during the operation, corosion will be encountered,and will need refinishing with suitable OEM coatings.
So it is worthwhile as neglecting these types of problems only leads to needless extra expense later on in the vessel's life.
And do check the hull to engine bed flange bonding is intact at the hull aperature, reinforcing with epoxy and cloth if in any doubt.It is a routine job for a marine engineer as the OP says, but only if the structure of the engine beds to hull bonding is intact.
 
Is that on yanmars, Volvos, or both?

Both...

Thanks for the explanation 'paulcan'... I believe we've discussed this very issue in the past.

Below is a link to a photo of a typical preformed/moulded engine bed for a saildrive unit. I believe this one is from a Yanmar. If you look at the photo, you'll see the see the bolt holes to fasten the sealing ring and the aperture in the moulding that allows the drive leg to drop down the boat hull. It is the sides of this aperture that needs meticulous bonding. Well worth checking while replacing the seal on their saildrive...

http://i125.photobucket.com/albums/p61/giuliettacsc/DSC01391.jpg
 
Angus,

by ' prolonged ' I meant - with preparation - a day or two dried out, so a few tides; not a career at it for some marine engineer. :)

Displaying your ignorance again. It is not a between tides job. The boat has to be out of the water in a cradle, engine disconnected and moved forward, drive removed, diaphragm replaced and re-assembled. About 8-10 hours work plus hauling and re-launching. This assumes the failure is in the outer rubber of the diaphragm. If it is a failure of the bond of the saildrive bed to the hull as discussed by paulclan and saxonpirate, more work!
 
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