450: Propeller Falling Off

[mdhanlon]

I purchased a new L450F through Dream Yacht Charter in June 2017. She was sailed to St. Vincent in Dec. 2017. I didn't want to post to the forum until I had had a chance to actually sail her.

I was just on her for the past two weeks and during that trip, her starboard propeller fell off. I spoke with the base manager from Dream and he indicated that he is having this problem occurring pretty frequently (4-5 lost props in the last 2 years). Our boat has only been in the water for 3 months, so it seems quite strange for this to have occurred.

Has anyone else had this problem and does this seem to be a design flaw with the current design?

I have the 55hp Yanmars with the SD60-5 saildrives.
Any help would be great.

[InTheDish]

I have heard that they pop off when you snag a line....it's a "protective" measure for your sail drives.

[hellosailor]

And you have inspected the retaining nut on the other prop and found no issues with it?

[Lepke]

At least your prop repair is cheaper than this guys.

[mdhanlon]

I did a quick check on the other retaining nut and it was not loose. I didn't do a thorough check.

[SV Bacchus]

Is there no locking nut, Cotter Pin or something to insure they don't loosen due to vibration? Sounds very strange to me..

[SV Bacchus]

Originally Posted by Lepke

At least your prop repair is cheaper than this guys.

I could buy a new boat for what that repair is going to cost!

[feebs]

What brand of prop is fitted to your L450? Did the complete prop come off the SD prop shaft?

[Aupalukii]

Happen to me a few times on my Lagoon 470 with SD40...I fix the problem installing a threaded shaft with two locking nuts to lock the big nuts in place....

[rom]

Originally Posted by InTheDish

I have heard that they pop off when you snag a line....it's a "protective" measure for your sail drives.

yes indeed. I have flexofold now, those won't pop off. But I may loose the SD and/or engine if I snap a rope. It's a choice ...

[boom23]

Never had a problem with flexofold on my ex L450...

Something is wrong. The props should not be falling off...

[InTheDish]

Originally Posted by boom23

Never had a problem with flexofold on my ex L450...

Something is wrong. The props should not be falling off...

I was told by the owner of a new L500 that it's by design. On my old 410 we just pull the prop with a wrench and clean out the fouled line in about 5 minutes.

[mdhanlon]

The props are the stock Lagoon fixed props. The lock nut and prop came off, but I managed to find the prop right under the boat in about 25' of water.

I've looked through the manual for the SD60 sail drives and there is mention of ensuring the correct torque is applied and I wonder if there was a quality control issue here.

[rom]

Originally Posted by mdhanlon

The props are the stock Lagoon fixed props. The lock nut and prop came off, but I managed to find the prop right under the boat in about 25' of water.

I've looked through the manual for the SD60 sail drives and there is mention of ensuring the correct torque is applied and I wonder if there was a quality control issue here.

ah, that is interesting because you can see if the prop is dead, is it ? I don't remember precisely but there is some kind of rubber part around the axis which would fail. If the prop is still fine then it may just be a question of proper torque & loctite.

[dayshine]

Originally Posted by rom

ah, that is interesting because you can see if the prop is dead, is it ? I don't remember precisely but there is some kind of rubber part around the axis which would fail. If the prop is still fine then it may just be a question of proper torque & loctite.

The rubber bearig thing you mention is only on fixed props, not the same om folding props.