Propeller change LH to RH: new shaft required?

[chrisD]

my replacement engine rotates in the opposite direction from the old one. Hence the prop needs changing from LH to RH. Is the thread on the end of the shaft only suitable for LH? Comments welcome.

 

[sarabande]

Does the present shaft have a lock tab, or a castellated nut plus split pin, to secure the prop ?

One assumes that the taper is suitable.

 

[chrisD]

it has a nut and a grub screw in the hub that prevents the nut from turning.

 

[Tranona]

No need to change. The nut is only there to stop the prop from coming off the taper. Irrelevant which way the prop/shaft rotates, the nut is fixed and locked to the shaft.

 

[scottie]

my replacement engine rotates in the opposite direction from the old one. Hence the prop needs changing from LH to RH. Is the thread on the end of the shaft only suitable for LH? Comments welcome.

do you change it every time you go into reverse ?

 

[bedouin]

No need to change - I replaced my engine (and therefore prop) a few years ago without changing the shaft and nothing has fallen off yet.

The prop is stopped from rotating on the shaft by a key and if the prop can't rotate there is doesn't matter which way the nut that secures it is tightened (plus that tends to be castellated too)

 

[Beneteau381]

No need to change - I replaced my engine (and therefore prop) a few years ago without changing the shaft and nothing has fallen off yet.

The prop is stopped from rotating on the shaft by a key and if the prop can't rotate there is doesn't matter which way the nut that secures it is tightened (plus that tends to be castellated too)

Pedantically speaking the taper and the key work together to stop the prop turning. ?

 

[NormanS]

I used to have an old Scottish 60' converted fishing boat, which was fitted with sterngear by Fleetwoods of Lossiemouth. Her 49" four blade propeller was held on in an interesting manner. The shaft was 3.5" diameter. A large cone nut with a relatively fine thread held the prop onto the taper, and then a bolt was screwed in through the tip of the cone nut, into a tapped hole in the end of the shaft. The large cone nut was a right hand thread, and the bolt, or set screw was left hand. It meant that there were no split pins or grub screws at all. It worked.

 

[scottie]

Kelvin stern gear did not use keys just a proper fitted taper with the propeller being lapped on similar to post #8
they also used sleeve couplings to join shafts again no key Just a split sleeve compressed

 

[Tranona]

I used to have an old Scottish 60' converted fishing boat, which was fitted with sterngear by Fleetwoods of Lossiemouth. Her 49" four blade propeller was held on in an interesting manner. The shaft was 3.5" diameter. A large cone nut with a relatively fine thread held the prop onto the taper, and then a bolt was screwed in through the tip of the cone nut, into a tapped hole in the end of the shaft. The large cone nut was a right hand thread, and the bolt, or set screw was left hand. It meant that there were no split pins or grub screws at all. It worked.

Same as a Volvo saildrive except the prop is on a splined shaft.