Votes for material for exhaust manifold water entry fixture?

[BenCT]

I'm replacing the brass/bronze fixture (not sure what it really was) that I took off my exhaust manifold. It is the 90 degree el fixture that receives hose from the thermostat. It is 1/2" npt.

I'd like to avoid brass so I don't have to worry about overtightening it. I see Moyer sells brass. I've heard people write about cast iron. What are peoples thoughts on stainless steel or bronze?

I just want something that I can remove in the future, will work with salt water and will be fine with the heat.

What are people's votes?

Brass, Bronze, Stainless or Cast Iron (what kind of cast iron?). Also, sources of your favorite fixture here are welcome.

[Dave Neptune]

Corrosion and rust are your two biggest enemies especially in a salty environment. Using iron as it is a matching metal helps with corrosion but gives you the ability to rust from the inside and the outside.

I suggest using a straight fitting if you have the height above the manifold as you will not need that extra turn to tighten. Since you have a tap you could dry fit and retap another partial turn to get a 90 degree fitting pointing the right way without overtightening, or just loop the hose an easier alternative.

Either way I would use Leak Lock Blue as my first choice for sealant and Permatex #2 as second. To me anything else is a distant third in a marine environment.

As for the fitting I would go with the stainless first and bronze second. There is no third unless it is an emergency repair that will be redone.

Dave Neptune

[ndutton]

Bronze or stainless are fine but even brass has not been a problem for (?) years. The only problem was upon removal and by your own conclusion was the result of over tightening on installation. Without the over tightening it would not have been an issue and as far as I can recall, has never been an issue on this forum. I replaced my factory original fittings (brass) after 40 years in place and they were still serviceable.

If your engine is raw water cooled I'd advise against iron of any kind unless you like dealing with rust.

[hanleyclifford]

[IMG]/home/hanley/Pictures/shopping.webp[/IMG]Black malleable iron street 90 - hands down

[joe_db]

I use bronze when able, brass otherwise, and have never had a problem with either one.

[Al Schober]

Personally, I used brass (local hardware store) for 30+ years without issue. Bronze or stainless would be better but difficult to source. First try would be McMaster.
Another consideration (while you're doing it) would be to make the low end of the manifold the INLET. When piped the other way, air collects in the high end of the manifold and will give you a hot spot.