Volvo Saildrive hub. What I didn't know.

[johnalison]

We've been sailing blithely around for fifteen years until we started to lose power in late June. At the time I thought that it was caused by weed, and there was in fact some weed on an underwater photo I took. It wasn't until we dried out in Jersey that I saw that something wasn't right about the saildrive hub. Although it was Saturday morning, an engineer was able to come (thanks, Oliver) and he diagnosed the fault and was able to get a replacement and fit it by the following Thursday.

I was unaware that these hubs are designed as a failure point and liable to fail, with the inner rubber bush becoming detached from the bronze outer shell. We had fouled some net three years ago, and some weed more recently, and I suspect that this might have caused the problem. I dread to think what might have happened if the failure had been worse mid-Channel with a ship approaching. I trust that folks check their gear more thoroughly than my engineers did last spring.

This seems to have happened to other people too. http://www.ybw.com/forums/showthread.php?214942-Bavaria-Volvo-Saildrive-Propeller-Hub-debonding

 

[bigwow]

I believe you can get a new splined insert fitted to the prop.

 

[Tranona]

They are not designed to fail - they are there primarily to isolate the prop electrically from the drive and provide a small degree of cushioning to reduce shock loads on the gears. they do potentially weaken over time and delaminate from the hub, but can be replaced in the bronze prop you have. Less easy with the standard aluminium prop as it can split under the pressure of pressing the new bush in.

Fitting a rope cutter will reduce the chance of fouling from nets etc and potentially prolong the life of the hub.

 

[johnalison]

Thanks. I'll remember that next time. I did see one article that referred to it as a designed failure point, but no one mentioned recycling the unit.

 

[Tranona]

Thanks. I'll remember that next time. I did see one article that referred to it as a designed failure point, but no one mentioned recycling the unit.

A specialist such as Steel Developments will replace the bush. The failure is not common, and is often caused by fouling putting load on the hub it was not designed for - but better this fails than wrecking the drive unit at £5k+ a time!

 

[sailaboutvic]

I fitted an rope stripper from Ambassador Marine when the boat was commission five years ago and it has got us out of an problem with nets a few time , work well and worth every penny .

 

[Allergy]

I fitted an rope stripper from Ambassador Marine when the boat was commission five years ago and it has got us out of an problem with nets a few time , work well and worth every penny .

+1

 

[savageseadog]

The Radice prop is very prone to this issue, I'm not sure if that prop is a Radice. You are fortunate that you didn't lose the lot (except for the inner part of the hub).
As a point of interest what you're referring to is the propeller hub, not the saildrive hub.

 

[bigwow]

The Radice prop is very prone to this issue, I'm not sure if that prop is a Radice. You are fortunate that you didn't lose the lot (except for the inner part of the hub).
As a point of interest what you're referring to is the propeller hub, not the saildrive hub.

Says Volvo Penta on it so not Radice.

 

[savageseadog]

Says Volvo Penta on it so not Radice.

Made by Radice for Volvo Penta?

Doesn't really matter, it can happen to any