Exhaust Elbow S/steel grade

[PabloPicasso]

But this link is to Ben in America!

And Ben's elbows are only 304 s/s. Not 316 which is really what is required

 

[JumbleDuck]

And Ben's elbows are only 304 s/s. Not 316 which is really what is required

Though no-one seems to be reporting any problems with them.

 

[Spyro]

And Ben's elbows are only 304 s/s. Not 316 which is really what is required

He's sold plenty, myself included. I don't know if he's been selling them long enough to know how they will last.

 

[Heckler]

Amazingly low prices but how does one set out to build a Yanmar elbow from these pieces? - I can't see a mounting flange or water injection point.

I used an injection point similar to this from Asap


http://www.asap-supplies.com/search/exhaust/seaflow-engine-exhaust-outlet-spray-head-2187360


I made the flange myself
S
PS The point I am making, 316 fittings and stock pipe is cheap and easily obtainable, so your fabricator is being??

 

[Pords]

I have recently received a new exhaust elbow from Ben. Good quality and excellent service and comms. Turns out my cylinder head had also corroded beyond repair. You hopefully all back up and running next week.

 

[RichardS]

The inner tube is welded into the outer, and the injection tube is also welded in. It is really difficult to get good welds here and they are sprayed with hot salt water which can cause corrosion. Also the hot salt water can be sucked back into the inner tube when the engine shuts down leaving the whole area damp. They corrode either at the welds or perforation of the inner tube.

Just taken off my 3YM30 port engine exhaust elbow today as I could see salt deposits on the heat exchanger below the elbow which seemed to be coming from the elbow although I can see no problem when the engine is running. Anyway, Tranona is absolutely correct. The elbow is stainless steel but when I cleaned and polished it both inside and outside (virtually no carbon or salt deposits after 3000+ hours) I could see a hairline crack in the outside weld as he says. It must be a very small leakage as I can put my palms over both ends of the elbow and suck a vacuum through the water injection point and the vacuum seems to hold until I get bored with holding it. Perhaps the crack lets sea water out but not air in only when it is hot?

The inside of the inner weld polished up fine with no cracks visible so there's no exhaust gas leakage.

Anyway, I cleaned up and roughened the outside of the weld and have plastered on a great "sausage " of Milliput expoy which withstands 130 degrees which is fine so lets see how that lasts. Might give me another season or two but presumably the starboard elbow will be on its way out although its not leaking at the moment.

Guess I'll have to buy two spares ready for the inevitable!

Richard