Thanks that's good news
.I ll watch some brazing videos as i have a torch already.
. Finally managed to lock in place the fittings with no welding just tightening! Having a look in the gas pipeline coming from the street and into the buildings, observed that they had used galvanized pipes and fittings oriented such as making their way in. By the way, all through hulls and seacocks on the boat are parallel thread and had to mark the though hull position before installing it, so the seacock handle will be on the wanted side. Unlike parallel threads where you reach the end and you can't tight more than a few degrees, the taper pipe threads can be tightened way more than one full round after they are hand tight, making it easy to seal exactly at the desired angle. Not sure if they are NPT or BSPT but doesn't matter since they are the same thread type. From left to right:
No need to remove the galvanising, it wont get hot enough to burn it off. You can wrap some fi glass tape over it to prevent it warming up your engine space. Thats what I did when I made my SS oneI miserably failed to learn to braze overnight, it looked very easy on the videos but bought rods and flux, started trying on some steel with embarrassing results.
- male taper flange to female taper part of the elbow, (the flange is custom made on a machine shop)
-male taper elbow to possibly parallel female bronze Y mixer, which is not an ideal connection but acceptable from what reading around.
The galvanizing of the elbow will be removed with citric acid to avoid getting poisoned by fumes when the engine runs...
Thank you all for your feedback! you really contributed to making this final version of the elbow which is robust, not heavy as the initial riser design, with easily replaceable parts.
I will update the thread soon after i make the fiberglass muffler.
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The mixer is around 400mm above the waterline. It is as cool as the seawater as the seawater mixes with exhaust inside the mixer.
Understood! That's a nice design, and now with SS looks very safe.
If it works well, guess i 'll replace both elbow and Y fittings with 316 SS in the near future. Unfortunately the Y fitting is CW617N yellow brass and not bronze (good for making a trumpet?) - not very optimistic about it holding for more than one summer! Problem is that few chandlers have bronze, most have normal brass and sell it as bronze. Recently polished water pump's cover, which is a Johnson made from real bronze in the early '70s and is still like new. If both alloys are polished, visually I can't see any difference between a yellow brass fitting and a bronze, very hard to tell.
The weight of the original elbow would be good to know, the 2 fittings including the fabricated flange, is maximum around 1,5 kgs.
Only if you give him the parts to be welded ready it shouldn't be expensive indeed. Problem is that at some point the welds will fail. Plumbing fittings will also fail, but thinking that can be easily and quickly replaced made it a more attractive approach. The custom flange cost 30 euros to fabricate, a fair price.
My SS one is still going strong after 8 years! Mind you it is made of schedule 40 pipe fittings
is it 316 or 304? Send some pics of your installation if you would like , i found very cheap 304 fittings on aliexpress , better than any iron ,steel or brass
316, I made an 8mm flange, welded a 2" short thread on to it, threaded a 45deg elbow on, then used an ASAP supplies threaded water injection tube and that was it.
