Prop shaft coupling nut size?

[seattledale]

Anyone happen to know the size nut on a 35mm propeller shaft at the transmission coupler end?  I'm hauling out in a few weeks to change the Volvo Penta shaft seal and that means I have to remove the shaft coupler near the transmission.  I'd like to have the correct socket on hand before I begin the project.

Thanks

Dale

[bratwurzt1]

Ours was 14mm on a 2003 S/O 35, not sure if that helps. 

[seattledale]

Thanks bratwurtz1.  It sounds a bit small for a 35mm prop shaft, but maybe it's smaller than I was expecting.  If you recall, are you referring to the thread size or the socket size?  I always get confused, as the socket measured across the flats is larger than the thread diameter. 

Thanks for the reply

Dale

[bratwurzt1]

Now that you mention it maybe it was a 15mm and I'm talking about the actual socket size. We changed the dripless and fought with sliding that coupler off for two days so my memory may be a little toasted. Bring a whole socket set things never go as planned on boat maintenance 🤣

[Don Reaves]

My 2004 SO35 has a 25mm prop shaft, not 35mm, so the size quoted by bratwurzt1 may not be relevant to your query.

[seattledale]

Thanks for the input, bratwurzt1 and Don.  Yes, I tend to agree with you, Don, you guys may have a 25mm dia prop shaft as your SO35s may be powered a bit different than my 43DS.  I definitely have a 35mm dia shaft.  Well, I'll try to be prepared as much as possible with some large deep metric sockets.  My collection in the large sizes isn't great but I think a lot of Autozones and no doubt other car parts outlets tend to stock the larger sockets.  Trouble is I cannot measure the nut until I separate the two coupling halves.  I fully appreciate what you are saying, bratwurzt1, about the difficulty of sliding the coupling off the shaft; the forums seem to be full of stories of triumph over adversities getting that coupling off.  Like one poster said, the nut is red-faced tight.  BTW bratwurzt1, I believe we sailed the same waters in your area of eastern CT; I grew up and learned to sail in East Lyme.  In fact, my current DS43 was originally from Newport RI before it was shipped out here to Seattle.

Thanks guys.  And anyone viewing this post that knows the socket size for the nut on the coupling on a 35mm shaft, I'd sure appreciate hearing about it so that I can have the correct socket in hand.

Thanks

Dale

[bratwurzt1]

Mar 15, 2024 17:37:24 GMT seattledale said:

Thanks for the input, bratwurzt1 and Don.  Yes, I tend to agree with you, Don, you guys may have a 25mm dia prop shaft as your SO35s may be powered a bit different than my 43DS.  I definitely have a 35mm dia shaft.  Well, I'll try to be prepared as much as possible with some large deep metric sockets.  My collection in the large sizes isn't great but I think a lot of Autozones and no doubt other car parts outlets tend to stock the larger sockets.  Trouble is I cannot measure the nut until I separate the two coupling halves.  I fully appreciate what you are saying, bratwurzt1, about the difficulty of sliding the coupling off the shaft; the forums seem to be full of stories of triumph over adversities getting that coupling off.  Like one poster said, the nut is red-faced tight.  BTW bratwurzt1, I believe we sailed the same waters in your area of eastern CT; I grew up and learned to sail in East Lyme.  In fact, my current DS43 was originally from Newport RI before it was shipped out here to Seattle.

Thanks guys.  And anyone viewing this post that knows the socket size for the nut on the coupling on a 35mm shaft, I'd sure appreciate hearing about it so that I can have the correct socket in hand.

Thanks

Dale

We have a slip at Spicer's marina in Noank and sail to RI on a regular basis. Great area to sail 😁

[seattledale]

I remember Spicer's marina.  Yes, good memories of sailing around there as a kid.  After high school I went to WPI in Worcester and then moved out to Seattle.  Now we have to be satisfied with the San Juan Islands north of Seattle for our cruising...actually, it's pretty spectacular   Yes, the 43DS I own (nee Kinvara) was bought new by a couple from Stuart FL who sailed it in Newport during the summer and back down to FL via Bermuda and Bahamas for the winter.  They sold it to a guy out here who had it trucked the 3000mi.  And I bought here a couple of years later.  Love the boat, thinking of sailing her down to Mexico as we did with our earlier boat.  But as the years roll by, I'm getting less and less confident on my off-shore abilities, ha!

Anyhow, have a nice summer there in New England!

Dale

[saltymetals]

Dale,
When you buy new nuts I strongly suggest you get Unlock and then also use a thread locker like Locktite or equivalent.

Yes, on my original setup mine came apart, nuts flew all over the place!
Andrew
"Genial Bee"

[seattledale]

Hi Andrew

Yes, I plan on using Locktite on the threads of the large nut at the end of the propeller shaft near the transmission coupler.  I've heard many stories of the prop shaft sliding out of the coupler when the propeller is in reverse thrust; I believe that nut is what prevents the shaft from pulling free.  Last night I was watching an episode of Sailing Millennial Falcon on YouTube when that happened to them while crossing the Atlantic.

Andrew, do you recall the size of the socket for that large nut on the end of the shaft?  My 43DS is 2005 with the Yanmar 4JH3.  I'm guessing your boat and mine are very similar.

thanks

Dale

[bratwurzt1]

Mar 17, 2024 21:39:45 GMT seattledale said:

I remember Spicer's marina.  Yes, good memories of sailing around there as a kid.  After high school I went to WPI in Worcester and then moved out to Seattle.  Now we have to be satisfied with the San Juan Islands north of Seattle for our cruising...actually, it's pretty spectacular   Yes, the 43DS I own (nee Kinvara) was bought new by a couple from Stuart FL who sailed it in Newport during the summer and back down to FL via Bermuda and Bahamas for the winter.  They sold it to a guy out here who had it trucked the 3000mi.  And I bought here a couple of years later.  Love the boat, thinking of sailing her down to Mexico as we did with our earlier boat.  But as the years roll by, I'm getting less and less confident on my off-shore abilities, ha!

Anyhow, have a nice summer there in New England!

Dale

Thank you and same to you

[fma]

Mar 13, 2024 1:43:45 GMT seattledale said:

Anyone happen to know the size nut on a 35mm propeller shaft at the transmission coupler end?  I'm hauling out in a few weeks to change the Volvo Penta shaft seal and that means I have to remove the shaft coupler near the transmission.  I'd like to have the correct socket on hand before I begin the project.

Thanks

Dale

My SO45 with the 35mm shaft needed a 36mm socket to remove the shaft coupler nut

[seattledale]

fma, 

Thank you Thank you Thank you!  I've been stressing out over this for weeks!  I'll go ahead and get a 36mm 6-point impact-rated deep socket from Amazon and have it in 2 days.  Which is a couple of weeks before haulout and I won't need to be running all over town trying to find one.  Fantastic!

When looking at my coupling last week, I didn't see any grub screw threaded perpendicular to the shaft that would prevent the nut from rotating, so I'm assuming they used Locktite on the nut thread.  My plan is to heat the nut with a propane torch for a bit once I have separated the coupling halves, and then break it lose.  Then I'll use a wheel puller to pull the coupling off the shaft.  Change the Volvo-Penta seal and put the shaft back into the coupling using Locktite Red on the nut threads.  A 36mm socket means the thread is probably M24 and it's looking like I should torque it to about 355N-m, 260ft-lb per the ISO table for tapered prop shafts I found on an Aussie website.  If you happen to recall, does that seem to be a reasonable tightening torque?

Again, thanks, I really appreciate the information!

Dale

[fma]

I took the nut off and treated the coupler with Kroil penetrating spray. Took a little heat, patience and a gear puller to get the coupler off, but you've got the idea.  Can't find my notes on the torque spec I'm afraid.

[seattledale]

fma,

Thanks for the pictures, very clear.  It appears your SO45 is identical to my SO43 in this area.  It's a dream having such easy access - just lift the fiberglass floor panel in front of the aft bed and everything is there in the open.  Compared with my old Columbia which involved slithering alongside the engine under the cockpit wondering if I could ever get out again.

Have a great sailing season there in FL.

Dale

[saltymetals]

Mar 18, 2024 21:07:16 GMT seattledale said:

Hi Andrew

Yes, I plan on using Locktite on the threads of the large nut at the end of the propeller shaft near the transmission coupler.  I've heard many stories of the prop shaft sliding out of the coupler when the propeller is in reverse thrust; I believe that nut is what prevents the shaft from pulling free.  Last night I was watching an episode of Sailing Millennial Falcon on YouTube when that happened to them while crossing the Atlantic.

Andrew, do you recall the size of the socket for that large nut on the end of the shaft?  My 43DS is 2005 with the Yanmar 4JH3.  I'm guessing your boat and mine are very similar.

thanks

Dale

Dale, Sorry in my earlier there was a typo. Certainly NOT "Ulock" but i meant Nylock nuts and then also add the locktite. I have another precaution which surprised a guy who was checkig for a leak on my 43ds. When we lifted the white panel to get at th prop shaft he could not understand why i had a shaft anode on the shaft INSIDE the boat when of course he was expecting only on the outside. My theory is that if those bolts ever come undone again there will be no chance of the shaft slipping out through the hole into the sea (with my expensive feathering prop!)
Yes, our boats are v similar , mine is 2004 , but i am at home in London at the moment, not on board so, sorry cannot help with size of the nut.
Best of luck
Andrew
PS: We set up a section specially for the Jeanneau 43ds on this website so you might find a lot of useful ideas there.

[seattledale]

Hi Andrew

Yes, good idea on the Nyloks for the four coupling nuts.  I also plan on adding a shaft anode inside the boat between the transmission and the seal for the same reason - if it ever leaves the coupling I don't want it flying out through the seal into the deep blue sea.  Then I'd have TWO big problems, ha!  However, I'm thinking of putting some sort of hard stop so that if the shaft ever did move backwards, the anode would hit the stop before crashing into and no doubt destroying the Volvo Penta seal.  I guess the good news is that I have a Gori folding prop so in theory, the blades should fold rather than be continuously spinning and being dragged back by the water resistance.  That's in theory of course; I still think I'll install that hard stop.

Yes, I generally look in the 43DS sub-group, but I also find a lot of useful hints in all the forums.  Have a fun sailing season.

Dale