Prop shaft woodruff key

[classic jenny]

An evenfull weekend left me with no propulsion forward of aft eventually diagnosed that the propellor was free spinning on shaft. The woodruff key had an argument with the prop shaft and propellor so decided to go and visit Davey :-(. According to my paperwork that came with boat it's a 1 inch shaft and the keyway is .25 wide. Was given the name of "lancing marine" to try but there email come help address just bounces back. Can anyone recomend anywhere else. Can't believe it won't be a standard size as some have told me.

 

[TOKOLOSHI]

https://www.google.co.uk/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=lancing marine

Works OK!

 

[classic jenny]

Yep then go into there website fill in the contact form hit send and it comes up with server erred there end

 

[Tranona]

www.lakesterngear.co.uk in Poole will sort you out. Probably about £15 machined to size.

 

[rogerthebodger]

An evenfull weekend left me with no propulsion forward of aft eventually diagnosed that the propellor was free spinning on shaft. The woodruff key had an argument with the prop shaft and propellor so decided to go and visit Davey :-(. According to my paperwork that came with boat it's a 1 inch shaft and the keyway is .25 wide. Was given the name of "lancing marine" to try but there email come help address just bounces back. Can anyone recomend anywhere else. Can't believe it won't be a standard size as some have told me.

Have you taken the propellor off the shaft as IMHO the key (which is a parallel key not woodroof) would have sheared and damaged the keyway in the shaft or prop or both.

Any pics.

 

[Bandit]

It will probably be a parallel key ie a rectangle of brass or bronze 1/4 in wide a good machinist looking at the shaft and prop can make you one otherwise.

Is your prop nut pink?

 

[earlybird]

The woodruff key had an argument with the prop shaft and propellor so decided to go and visit Davey.

As said, a parallel key, almost certainly square in cross section, ie. 1/4" square. However, a key shouldn't be able to exit the keyway when it feels like it!
The keyway cut in the shaft should be of such a length so as to trap the key within the boss of the prop. If it doesn't, then the new key might go AWOL. Needs checking.

 

[rotrax]

In case you are not aware, the key-woodruf or square-is just a locator.

The tapers on the shaft and in the prop are designed to take the driving loads and the prop MUST be a perfect fit on the shaft taper for trouble free long term reliability. Lapping in with grinding paste achives this, unless the taper has been damaged. If so you might need pro help.

The correct procedure is to fit the prop onto the shaft by hand, pushing it home hard, without the key fitted. Mark the shaft at the rear of the prop-I use a turn of insulating tape . Remove the prop-might need a tap if it is a good fit in the taper-and re-fit the key and the prop. The rear of the prop should come to EXACTLY the turn of tape.

If it does not, the key is stopping the prop engaging fully onto the taper. A little hand fitting by filing the top of the key is required. Tightening the nut at this point will allow the key to take the drive forces, which it is not designed to do and is not strong enough to do.

I hope I am not teaching the proverbial granny, this info is given with the best intentions.

Good luck with the repair.

 

[Topcat47]

I made mine by hand using files and a hacksaw. It doesn't have to be milled and ground.

 

[rotrax]

I made mine by hand using files and a hacksaw. It doesn't have to be milled and ground.

Exactly-almost any metal will do as it is only a locator and not intended to take ANY driving forces.

After 45 years+ of repairing motorcycles I became pretty knowledgeable about tapered shafts and keyways............................