Lost propeller

[Scorcher IV]

All set for a sunshine filled cruise to Arran (in Scotland, sun in Scotland!!) when just as we left the Marina no drive, fortunately we had enough way on her and wind over the starboard quarter so we lifted out into safe water. Checked the cables and top of the sail drive leg and then called the Marina for a tow back in. When lifted out no propeller just the central boss. Don't you just love sailing!!

2016-05-28 15.02.25.jpg

[MarkTheBike]

well, on the bright side, just think how much faster you can go without the prop drag....

ok, not funny but welcome to the forum anyway.

[Yngmar]

Any evidence as to what happened? Locking screw broken, or no Loctite on it? Or wrapped something round the prop that tore it off?

[Scorcher IV]

No idea really one minute happy motoring along next no drive, the cone and locking screw are still on, it seems that the prop has either hit something and split in two or worked its way off the rubber central boss.

[MarkTheBike]

I assume that your first post should have had a photo attached but there's nothing showing up except for a bit of text (referring to a jpg). I guess it was a  picture of the remains. It would be interesting to have a look if you wouldn't mind having another shot at uploading it... thanks.

[MarkTheBike]

Hi Scorcher

Nope, still nothing showing - just text. Click 'Additional Options...' below the text box you're typing in and you'll see a 'Browse' button. Click that to upload a picture...

Cheers

[Scorcher IV]

Hope that shows it now

[Aquila]

This is interesting as I have not seen a picture like that before.  Unfortunately Volvo props have been known to drop off for the following reasons.

If the prop is ever strained maybe by a rope of something the prop moves on the rubber centre boss.  Overtime it's possible that the rubber boss is push aft so as the prop turns it can unscrew the cone which has the same thread as the prop.  The left hand prop can undo the left hand locking cone.  This is why when you have you boat lifted you should inspect the prop and pay particular attention to the central rubber boss.  I was informed that the plastic type large washer that sits between the cone and the prop should turn easily, if it does not then the prop is moving on the rubber boss.

In your case of your prop I think either the prop has been damaged over time and spun of the central boss, although not sure it could slip over the cone or as it has move on the rubber boss that it had fractured.  I am not an expert on this but had an interesting conversation with a guy last year who was clearly an expert in this area. 

[Scorcher IV]

I have searched and have not found much relating to Volvo props falling off in this way. The boat was only surveyed 10 months ago and the prop and stern gear rated good by a very competent surveyor who was highly recommended by more than one person in the marina. It has either failed due to age and corrosion or more likely been hit by something that has shattered the central casting around the rubber, as that is the only way it could come off. However it will be interesting to see what my insurance company think of it. It was a two blade fixed aluminium propeller.

[Aquila]

Have a chat to the engineer at Ambassodor Rope Cutters in Winchester....very interesting conversation. 

[Yngmar]

Thanks for the photo. The smoothed rubber looks like the propeller spun on it for some time before falling off. It also looks like there's some wear on the cone where it rattled around on it. On mine, the propeller wouldn't fit over the cone even with the rubber gone.

If you hit something so hard your propeller gets spun off the rubber, you would surely have heard the thud. It seems more likely that the damage occurred either in a previous incident or from wear over time and it finally let go all the way.

[Scorcher IV]

Just as an update my insurance company "Yachtline" have agreed the claim is reasonable and have told me to go ahead with the repair.