Would you buy a boat with Boat Pox /minor osmosis?

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Seegull

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We have found a great little sailing boat, 25ft 1987, same owner for over 30+, looks like the most well looked after boat I have seen.

BUT! The hull has lots (not just in one area) of small blisters (5 - 10mm) - sometimes referred to as boat pox.
He did mention it has "only" had osmosis in two small spots at the very forward part of the hull, which he had repaired.
The small blisters do not count as osmosis to him, he is over 80 and has obviously obsessively cared for the yacht for decades.

The boat has only been in fresh water and always winters on land.

Is this something that just has to be accepted with boats of this age?
Would you still buy it?
Or is this a case of signing up to a big issue which will just develop expensively in the near future?

Advice appreciated.
 
Depends on the price, and the model, I made a mistake when I bought a 1986 boat, although it had some osmosis I knew I could fix that as I once had a car bodyshop but the mistake I made was I should have bought a bilge keel boat. When I came to sell nobody wanted to know, but if you buy a bilge keeler you dont need a boat cradle to store it at a marina and you can get a mooring that dries out.
Plus the other mistake was the engine was a 50 hp BMC Thornycroft Diesel and parts are unobtainable, whereas the smaller BNC diesel spares are easier to find.
Is your boat an inboard or outboard.
 
I did once, she was striped dried and epoxyed then coppercoated ...no problem, just a bit of money which was a saving with no antifouling for 10 years .Get quotes. No boat has ever sunk with osmosis.
 
Seegull said:
Is this something that just has to be accepted with boats of this age?
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Pretty much. There are exceptions, but most boats of that age will have a few blisters.

Seegull said:
Would you still buy it?
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If she feels like the right boat for you, absolutely. Deal with the blisters when you're out of the water for the winter if you can be bothered.

Just be prepared for a sucking of teeth and a lower offer when you come to sell. Of course, there's nothing to stop you doing the same to the current seller

Seegull said:
Or is this a case of signing up to a big issue which will just develop expensively in the near future?
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Almost certainly not. Osmosis that's a real problem has blisters the size of dinner plates, and the real problem isn't the osmosis, it's a defective layup.
 
Osmosis is even more common in fresh water because of geater osmotitic pressure. I has aRS400 develop blisters through sitting on a wet trolley cradle. It really is a non event, don't worry about it and don't do anything about it
 
Did you try to open some ?

I walked away from a boat after a survey due to osmosis. I knew the boat had some but when I pushed (finger) on one it burst. They were all over the hull. It was otherwise a nice boat.
 
It depends on the maker, model and price. I turned down a boat when the survey showed that the hull below the water line was extensively covered in small blisters. I wanted a boat that could be sailed without going into a shed for a few weeks for repair in the near future, but if the price had been £10 grand lower I would have bitten the seller's hand off.

I know that osmosis won't sink a boat but it does torpedo the price. Also it doesn't just appear underwater, I had a boat which had carpet glued to an area of deck underneath the sprayhood. I thought this was a daft idea as, when the wind was from astern the carpet got wet if it was raining. One winter I removed the carpet and found small bubbles as described above in the gel coat. These were removed, along with the gel coat in the area, and after filling and fairing off deck paint was applied. I never had any more problems in the area.
 
Maybe need to look at it on the basis that you might not easily be able to re-sell it - (see another thread on a Sadler 32) - and allow for some money at the end to scrap it, - if it suits your purpose for now and everything else is OK -intending to keep in sheltered waters say -and you can't find another one locally that would suit you without problems - is it still good value to you - Can you fit an outboard on it if the engine goes wrong - Look at the buying and scrapping cost in comparison with prices of holidays or activities for the amount of time you hope to use it - like once you come back from a holiday, that money is gone forever

Also need to check the insurance situation.
 
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Seegull said:
[...]
Is this something that just has to be accepted with boats of this age?
[...]
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No.

The yacht I sold less than two years ago had been launched in 1967, (the hull was moulded by Tylers Ltd ).

There was never any sign of osmosis during the 27 years I owned her, or when I sold her.
 
Poignard said:
No.

The yacht I sold less than two years ago had been launched in 1967, (the hull was moulded by Tylers Ltd ).

There was never any sign of osmosis during the 27 years I owned her, or when I sold her.
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With respect, not quite right and possibly misleading.

Osmosis and blistering in boats built in the 1960s - late 80s is common but not universal.
 
Poignard said:
No.

The yacht I sold less than two years ago had been launched in 1967, (the hull was moulded by Tylers Ltd ).

There was never any sign of osmosis during the 27 years I owned her, or when I sold her.
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Tylers only used gel coat above the waterline and just polyester resin below the waterline. Very few other boat manufacturers of that period followed their policy. Tylers were well known for moulding concrete parts for light industrial buildings and farm barns. How do I know so much? John Tyler was a member of my yacht club and my late father used to chat with him along race against him. Very decent chap.
 
Concerto said:
Tylers only used gel coat above the waterline and just polyester resin below the waterline. Very few other boat manufacturers of that period followed their policy. Tylers were well known for moulding concrete parts for light industrial buildings and farm barns. How do I know so much? John Tyler was a member of my yacht club and my late father used to chat with him along race against him. Very decent chap.
Click to expand...
I never knew that.

Presumably they found gelcoat is less resistant to osmosis than plain polyester resin?
 
Seegull said:
We have found a great little sailing boat, 25ft 1987, same owner for over 30+, looks like the most well looked after boat I have seen.

BUT! The hull has lots (not just in one area) of small blisters (5 - 10mm) - sometimes referred to as boat pox.
He did mention it has "only" had osmosis in two small spots at the very forward part of the hull, which he had repaired.
The small blisters do not count as osmosis to him, he is over 80 and has obviously obsessively cared for the yacht for decades.

The boat has only been in fresh water and always winters on land.

Is this something that just has to be accepted with boats of this age?
Would you still buy it?
Or is this a case of signing up to a big issue which will just develop expensively in the near future?

Advice appreciated.
Click to expand...
Yes - If it’s reflected in the price. I’ve bought and sold a 1960’s Contessa 26 and a 1980’s SHE 32 both of which had the pox, both solidly built which gave me years of cheap sailing around Ireland, Scotland, Faroe Islands and France. The former I sorted out the pox myself (dry, grind out, wash/rinse, fill with Watertite, coat with Primocon, AF and go sailing) The latter I just left it.

No - If it’s NOT reflected in the price - I walked away from another more expensive yacht purchases (twice on different boats) after paying for a survey that revealed Osmosis which had not been declared by the sellers and I didn’t wish to loose a season/time fixing. There are plenty of boats out there which don’t have it or where it’s been professionally remedied.
 
If you read up on the subject you will find that osmosis that results in blisters comes mainly from the inside due to poor layup or materials that leave styrene in the matrix. In other words it is there from the day the hull was moulded. Clearly some moulders were better at it than others but equally it can vary in different hulls from the same moulder. Osmosis is the process by which fluid passes through membrane and it is the fluids left in the matrix going out through the gel coat that causes the damaging blisters. There is also water going the other way but this is slower and does not generally do much harm to the matrix. However it often results in lots of small blisters which tend to disappear when the hull is out of the water and dried out. Complicated subject.
 
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