Engine exhaust stack problems

[wergie]

OK you lot, listen up and pay attention at the back there.

I have a problem with my engine exhaust stack, or rather the lack of one.

What I have got is a 3 and a 1/4 inch (82mm) OD cast iron boss on my engine room roof  and what I would like is a hinged foldy down exhaust stack to fit on said boss.

Now, I can get a 3inch hinge from Tony Redshaw, so what I really need is a 31/4'' to 3'' reducer, or failing that some 31/4 OD steel tube, though it appears to be easier to find unicorn poo.

Has anyone else had this problem and does anyone know why a 3 1/4'' boss was ever invented.....I'm sure theres a special place in Hades for the people behind it..

Over to you..

Steve

 

 

[RLWP]

Bet the boss has some standard thread on the inside

[ditchcrawler]

5 minutes ago, wergie said:

OK you lot, listen up and pay attention at the back there.

I have a problem with my engine exhaust stack, or rather the lack of one.

What I have got is a 3 and a 1/4 inch (82mm) OD cast iron boss on my engine room roof  and what I would like is a hinged foldy down exhaust stack to fit on said boss.

Now, I can get a 3inch hinge from Tony Redshaw, so what I really need is a 31/4'' to 3'' reducer, or failing that some 31/4 OD steel tube, though it appears to be easier to find unicorn poo.

Has anyone else had this problem and does anyone know why a 3 1/4'' boss was ever invented.....I'm sure theres a special place in Hades for the people behind it..

Over to you..

Steve

 

 

Not the same size as you want but I got my local garage to buy me a length of car exhaust  piping

[hider]

If these are BSP threaded fittings, the pipe size is the internal diameter not the external. 3 1/4" OD would be possibly 2 1/2 "  BSP.

" 

[jake_crew]

Beware of the way BSP pipe fittings & thread sizes are described.

 

3" BSP has an o/d of 87.884 mm or 3.46 inches.

 

If your pipe measures 82 mm o/d, I'd suggest its a thread size of 2 3/4 BSP.

 

 

Edited June 5, 2019 by jake_crew

[wergie]

OK chaps, thanks for your prompt replies and input. Now, my boss has a 2 inch BSP thread on the underside, which the engine exhaust screws into. The outside part is not threaded at all, its the same as a solid fuel stove flue in that respect, the flue stack should just sit on the boss. The boss itself is 65mm high .

[Bee]

What you need is an old fashioned plumbers merchant, or a new fangled one with a 60 year old bloke behind the counter. In the meantime I would try googling grey iron plumbing fittings and see if that helps.

[hider]

Where are you Wergie?

[wergie]

I'm in London but my boat lives in Warwick

[David Mack]

3 hours ago, jake_crew said:

Beware of the way BSP pipe fittings & thread sizes are described.

 

3" BSP has an o/d of 87.884 mm or 3.46 inches.

 

If your pipe measures 82 mm o/d, I'd suggest its a thread size of 2 3/4 BSP.

 

 

 

Or if it is a black iron socket like that below, then 82mm OD, is probably  a 2 1/2" BSP thread internally.

 

 

[Captain Fizz]

So, let's get this correct,

you need a bush that is 3 1/4 id by3od?

[wergie]

Not a bush as such, I need a piece of tube about 8 inches long, 31/4 id at one end, 3''od at the other.

[Captain Fizz]

10 hours ago, Bee said:

What you need is an old fashioned plumbers merchant, or a new fangled one with a 60 year old bloke behind the counter. 

Now that really is "unicorn poo"

If it ain't made of plastic they won't have a clue!

[bizzard]

You could try BSS ''British steam services'' who should have every steal pipe fitting known to man. Big PDF file though.  Section 74 Metal pipe systems.

[RLWP]

4 hours ago, wergie said:

Not a bush as such, I need a piece of tube about 8 inches long, 31/4 id at one end, 3''od at the other.

If your boat is in Warwick, Rose Narrowboats make bespoke chimneys