Jointing compound for Seacock into Saildrive

[Hoist]

Can anyone recommend an appropriate jointing compound for a seacock going into a Volvo Penta 120 sail drive.

I've noticed its straight threads rather than taper and so I think that requires jointing compound not gasman tape ???

 

[Baddox]

Some years ago I used https://clesse.co.uk/product/clessetite-thread-sealant-50ml-tube/
and it has been OK since. It needs contact with metal to cure so won't work for plastic only fittings.

 

[Boater Sam]

If its male and female straight threads I would suggest a locking thin nut as well as sealant to prevent rotation. Metal to metal I would use a Loktite product.

 

[xyachtdave]

Can anyone recommend an appropriate jointing compound for a seacock going into a Volvo Penta 120 sail drive.

I've noticed its straight threads rather than taper and so I think that requires jointing compound not gasman tape ???

Are you sure about the threads?

Pretty sure it’s a tapered thread in the sail drive, did this job earlier in the year, used Loctite 577 which is excellent.

 

[Hoist]

I will double check Dave.

thanks for the info

 

[sawduster]

Did this recently for a 130s. The original metal seacock and insert looked very corroded so thought it worth replacing them. Took them off and turns out it was just surface corrosion on the insert but the seacock ball was very tired. It more or less destroyed them taking them off with a nut extractor and an impact driver as there was no space for anything else.

Replaced the insert using a trudesign through hull with the flange cut off, and then put a trudesign seacock on that. No more metal corrosion and very happy with it. Worth considering if you haven't already bought all your parts.

 

[xyachtdave]

The thread in the saildrive was definitely a taper, 1995 120s.

Volvo Penta Saildrive Seacock ball valve Bronze, DZR, stainless

I took the old Volvo item off, took it to chandlers and got the elbow, valve etc I needed and it all fitted together fine, went back to boat, couldn’t get anything even 1/2 a turn into saildrive as the old tapered threads fitted into the new parallel bit but don’t work the other way round.

This was in the summer, Volvo replacement was out of stock in UK and £150.

 

[PCUK]

Any polyurethane sealant (such as Sikaflex) will lock and seal it although adding a locknut will improve the locking.

 

[Moodysailor]

Loctite 577 is the way to go.

 

[PaulRainbow]

[Deleted quoted content removed]

AI crap is forbidden on the forums. It's unreliable and potentially propagates rubbish answers.

 

[Moodysailor]

AI crap is forbidden on the forums. It's unreliable and potentially propagates rubbish answers.

A lot of care needs to be taken relying on AI but FWIW, that answer is not actually wrong - the S/D housing does indeed have a parallel thread (BSPP), and most standard fittings are tapered (BSPT). The idea of using BSPP is so the handle can be lined up in any orientation and then the lock nut tightens down the fitting. With BSPT, it lands where it lands.

It does nothing to answer the OP question though,

 

[PaulRainbow]

A lot of care needs to be taken relying on AI but FWIW, that answer is not actually wrong - the S/D housing does indeed have a parallel thread (BSPP), and most standard fittings are tapered (BSPT). The idea of using BSPP is so the handle can be lined up in any orientation and then the lock nut tightens down the fitting. With BSPT, it lands where it lands.

It does nothing to answer the OP question though,

But the point is, no AI allowed on the forum.

Thread 'AI Generated Content'

15 Oct 2025

The YBW forum is a community of likeminded individuals with a common interest. The purpose of the forum is to interact and converse with others interested in boats, sailing and the sea. Forum members build up a coterie of people who can be trusted.

On that basis there is no place for wholesale posting of AI generated content - which has been shown, on several occasions, to provide inaccurate data.

By all means consult AI off-forum, but posts on-forum should be in the words of the individual. A personal communique with other community members, sharing information drawn from one's own...

• Forum Admin Team
• Replies: 0
• Forum: Practical Boat Owner's Reader to Reader

• 

 

[Moodysailor]

But the point is, no AI allowed on the forum.

Thread 'AI Generated Content'

15 Oct 2025

The YBW forum is a community of likeminded individuals with a common interest. The purpose of the forum is to interact and converse with others interested in boats, sailing and the sea. Forum members build up a coterie of people who can be trusted.

On that basis there is no place for wholesale posting of AI generated content - which has been shown, on several occasions, to provide inaccurate data.

By all means consult AI off-forum, but posts on-forum should be in the words of the individual. A personal communique with other community members, sharing information drawn from one's own...

• Forum Admin Team
• Replies: 0
• Forum: Practical Boat Owner's Reader to Reader

• 

I don't read that as AI is forbidden, only that wholesale posting is not allowed - which makes sense. If entire threads are created and replied using AI, that is wholesale and is likely to end up with innacurate answers. I don't see that one comment in a thread can be regrded as wholesale anything irresepctive if its a cut & paste search engine, AI or human reply.

A general comment, there is enough misguided, out-dated and in some cases blatantly wrong information on this forum propagated by humans that makes the "inaccurate data" reasoning a bit dubious. I get the need to keep AI out in order to have genuine human interaction, but there is no need for a draconian response just because someone happened to use a computer to generate what was an entirely accurate statement in this case.

 

[PaulRainbow]

I don't read that as AI is forbidden, only that wholesale posting is not allowed - which makes sense. If entire threads are created and replied using AI, that is wholesale and is likely to end up with innacurate answers. I don't see that one comment in a thread can be regrded as wholesale anything irresepctive if its a cut & paste search engine, AI or human reply.

A general comment, there is enough misguided, out-dated and in some cases blatantly wrong information on this forum propagated by humans that makes the "inaccurate data" reasoning a bit dubious. I get the need to keep AI out in order to have genuine human interaction, but there is no need for a draconian response just because someone happened to use a computer to generate what was an entirely accurate statement in this case.

Seems clear to me : "By all means consult AI off-forum, but posts on-forum should be in the words of the individual. A personal communique with other community members, sharing information drawn from one's own knowledge and experience.

Please, keep it human."

Post #6 is neither.

If inaccurate AI answers are posted the next time a similar question is asked anywhere on the internet AI is likely to use the inaccurate post as reference material, perpetuating and reinforcing the error.

 

[Moodysailor]

Seems clear to me : "By all means consult AI off-forum, but posts on-forum should be in the words of the individual. A personal communique with other community members, sharing information drawn from one's own knowledge and experience.

Please, keep it human."

Post #6 is neither.

If inaccurate AI answers are posted the next time a similar question is asked anywhere on the internet AI is likely to use the inaccurate post as reference material, perpetuating and reinforcing the error.

Post #6 started with a clear statement that it was an AI generated answer, they also finished off with some very human sentiment

AI says this, obviously resellers are not saying what they are using.

I'll try it and if it feels dodgy ill switch to the taper

You are very well respected Paul, rightly so. But there is no need to be so harsh on someone who used AI and put it in a human context.

 

[Gixer]

I used Loctite 577 on my raw water intake seacock which was quite a loose fit. Worked perfectly, impressive stuff.

 

[Hoist]

I wrote this bit myself - Not copied and pasted...

Google said that the fitting on a 120S is a straight thread.

There you go. "No AI rubbish". Wrote it myself

The local Volvo guy told me today that the early ones can be tapered and the newer ones can be straight.

I'll try the straight one I've ordered since the boat is a 2001

 

[xyachtdave]

I wrote this bit myself - Not copied and pasted...

Google said that the fitting on a 120S is a straight thread.

There you go. "No AI rubbish". Wrote it myself

The local Volvo guy told me today that the early ones can be tapered and the newer ones can be straight.

I'll try the straight one I've ordered since the boat is a 2001

That solves that one then, as I said there was definitely a tapered thread on mine which caused much disappointment when I arrived at the boat with my bag of parallel fittings!

 

[stav]

Is the sail drive aluminium? Won’t there be significant corrosion if a bronze fitting is installed? I know I had to replace a tmp gearbox due to brass coolant fittings being used and the casing had corroded away…… surely a trudesign would be a good way forward? Only asking just to raise the issue, I have no knowledge other than stated experience. Good luck with it. (Polymer based is a bit scary, especially where there could be vibration). Good luck with it.

 

[Hoist]

I've given it a good coat of looking at today.

It seems the extension piece is very well into the sail drive and not leaking.

there are signs that the fitting after the seacock have been weeping a bit and are a little green.

I have a new guidi non stick seacock so rather than disturbing the extension piece i am going to reuse it

thanks all for the input