GORI Folding props falling off

[mavasu]

I have a Leopard 40 with yanmar sd20 sail drives with no holes in shaft and 2 TWO BLADE GORI props have fallen off installed by a reputable yard.Allegedly torqued appropriately.

A suggestion was made to use tabbed locking washers to fix the problem.Anyone have experience with these?

 

[Ron20324]

Is this a folding prop? No keyway slot on the shaft? Just a bolt in the end of the shaft to hold it on? At the least, a threadlocking compound should be used.

 

[kloudie1]

Sounds like the tapers are mis-fit. Check out Maine Sail's site for excellent advice on how the prop and shaft has to be lapped together for a proper fit.

 

[fstbttms]

It's a saildrive. There are no keyways, there are no tapers. The prop fits on a splined shaft.

 

[kloudie1]

Oops.. I see now, SD20. Ya right, fstbttms.
Tabbed lockwashers are common on things like auto axle nuts for locking, but they need a flat to keep them from turning..
I haven't found a diagram of how the folding prop is supposed to lock on, but from this old post in PDQ Cruising Forum, your problem may not be unique:
stumbled across this link to a parts diagram for the lower unit of the SD20 saildrive and thought it might be helpful to someone:

http://www.cruisersforum.com/forums/att ... 1210030280

It appears to be a page from the Yanmar shop manual and it includes part numbers. I needed to replace the prop shaft which snapped into as the boatyard was replacing my props. It snapped into because my evil PO had drilled a hole though it sideways for a cotter key. Apparently, he didn't like Yanmar's design for keeping the prop on the shaft. The shaft, not counting bearings, seals or labor cost $509.00 -- ouch! So far, the other shaft seems to be holding together OK.

Moral: Don't be tempted to drill a hole through your prop shaft.

Phil McGovern
s/v Sunshine
36036

PS: I now have two props -- one folding and one fixed -- for sale. If you are interested in them, give me a call at 317-366-8083.

 

[centerline]

why not use 2 nuts together, to lock them from coming loose. if you dont have enough threads for 2 nuts, use 2 "jam" nuts together...

I have seen bronze nuts with the nylon insert also... or loctite... several options.

and no matter how reputable the shop is, its the man doing the work, and his experience, knowledge and ability to understand the real problem that counts when it comes to things like this.
even the most reputable shops have less experienced people working for them... or people that THINK they know..

 

[fstbttms]

OK, again- the boat has saildrives, not shaft drives. The prop isn't secured like fixed blade props. Even it the boat had shafts, Gori props are attached with barrel nuts, not a jam and king nut like fixed blade props.

 

[centerline]

OK, again- the boat has saildrives, not shaft drives. The prop isn't secured like fixed blade props. Even it the boat had shafts, Gori props are attached with barrel nuts, not a jam and king nut like fixed blade props.

so the options are limited. loctite is still on the list...