Nut on folding prop.

Sneaky Pete

Sneaky Pete

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Servicing the folding prop it's a Volvo penta make. In the pictures which way CW or CCW does that nut turn to separate from daildrive.

Thanks
 

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On my previous boat the volvo 2 bladed folding prop undid in the usual lefty loosey manner. There was a small central bolt and larger bronze nut held together securely by a tab washer.

To undo that nut I'd put a socket on, then insert a prop blade as far into its castlated gap as it'd go, rotate blade/hub into a horizontal postion, support the blade edge beneath on a stout plank wedged against the ground to stop the whole thing rotating when I put in the extension bar and socket driver to undo.

But you knew all that.

From your photo it looks like you've already removed the tab washer and central bolt.
 
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Our props were 3 bladed Volvos.

You need a very large socket to remove the large nut. The large socket was bigger than the one in my socket kits (I have normal sockets and long sockets) and I had to source a new socket - and sourcing single big sockets is not easy. I don't recall how big - but I could check. The tab washer is one use only, the tabs work harden and break off quite easily. If you are lucky, as there are lots of tabs, you might use one tab for one installation and still have an unused tab for the next installation. Tab washers are cheap - I would not try to save money

I don't trust the tabs - and use blue Loctite as well.

I don't recall that you need to torque up the inner bolt nor the big nut. Its the tab washer holding it secure, and the fact the threads on the little bolt and big nut are 'different', hence my use of blue Loctite.

You obviously need the engine in gear - ideally held stationary in addition to being in gear.

If its fouled its easier to clean the prop on the shaft, I used a steel brush on an angle grinder - which keyed the prop for painting. Once you have cleaned the prop handle it with gloves, grease from you hands will reduce the effectiveness of the key.

Jonathan
 
You might want to check this but the big nut 'inside' the hub might accept a 30mm socket. I'm doing this from memory :)

The large nut, and even the small nut, will surely vary dependent on the size of the hub and/or props? Our props, 3 blades, must have been 'about' 200mm diameter
 
You need to flatten the tab washer (looks like it’s still there) which is folded up alongside one of the hex flats. Do this with a big screwdriver and gentle hammer tapping. Then find a quality socket set that fits.
I found difficulty in stopping the hub rotating. To solve this problem I got a length of good quality wood and shaped one end to fit very snugly into the jaws where the blades fitted and long enough to jam against the bottom of the boat to stop rotation. This bit of wood has worked for years and allows me to get some torque on.
Only re tighten to the recommended torque setting and don’t use any locking gue on the big bolt only the little one that is in the centre of the bigger bolt. If you do you will struggle to get it off in future
 
Neeves said:
You obviously need the engine in gear - ideally held stationary in addition to being in gear.

If its fouled its easier to clean the prop on the shaft, I used a steel brush on an angle grinder - which keyed the prop for painting. Once you have cleaned the prop handle it with gloves, grease from you hands will reduce the effectiveness of the key.

Jonathan
Click to expand...
Why have the engine in gear? I'd be worried loading the gearbox up in a way its not designed for might cause expensive damage.
Not necessary. Stop the prop hub rotating as I described above in post #2
 
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Halo said:
You need to flatten the tab washer (looks like it’s still there) which is folded up alongside one of the hex flats. Do this with a big screwdriver and gentle hammer tapping. Then find a quality socket set that fits.
I found difficulty in stopping the hub rotating. To solve this problem I got a length of good quality wood and shaped one end to fit very snugly into the jaws where the blades fitted and long enough to jam against the bottom of the boat to stop rotation. This bit of wood has worked for years and allows me to get some torque on.
Only re tighten to the recommended torque setting and don’t use any locking gue on the big bolt only the little one that is in the centre of the bigger bolt. If you do you will struggle to get
Click to expand...
The central bolt and tab washer have been removed already.
 

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Method for undoing the volvo hub nut

You will need the right size socket, extension bar, and decent driver bar.

Insert the prop blade as far as you can with a socket on the nut.

Apologies for my poor drawing, I'm not an artist 🤣
 

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Neeves said:
You might want to check this but the big nut 'inside' the hub might accept a 30mm socket. I'm doing this from memory :)

The large nut, and even the small nut, will surely vary dependent on the size of the hub and/or props? Our props, 3 blades, must have been 'about' 200mm diameter
Click to expand...
Thanks I'm using a M24 socket I'm hoping that it's right hand, but it feels like it is seized I know it's not it just tight.
 
PabloPicasso said:
On my previous boat the volvo 2 bladed folding prop undid in the usual lefty loosey manner. There was a small central bolt and larger bronze nut held together securely by a tab washer.

To undo that nut I'd put a socket on, then insert a prop blade as far into its castlated gap as it'd go, rotate blade/hub into a horizontal postion, support the blade edge beneath on a stout plank wedged against the ground to stop the whole thing rotating when I put in the extension bar and socket driver to undo.

But you knew all that.

From your photo it looks like you've already removed the tab washer and central bolt.
Click to expand...
Yes both are now off, I'll try your method of rotation prevention. M24 socket on nut very tight. Thanks.
 
I was a bit, very, twitchy on using heat. I understood the prop was constructed with a polymer sleeve (which may be totally incorrect) and applying heat to the nut might damage the sleeve (if it exists). Penetrating oil would be my first port of call or WD 40. If the shaft is immobilised you should be able to apply plenty of grunt.

Jonathan
 
Sneaky Pete said:
Yes both are now off, I'll try your method of rotation prevention. M24 socket on nut very tight. Thanks.
Click to expand...
Yes, give it a go. Stopping the whole thing turning is likely the issue.

If that doesn't work, and you're stuck, see if you can borrow a dewalt (or similar) battery powered impact driver, but make sure you use the special sockets designed for use with them.

Ask around the yacht club/boat yard etc. Someone is likely to have one!!

If you're really stuck hire, or even buy one 😮. They're useful kit and doubtless will get used elsewhere.
 
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