Don’t use brass below the waterline!

Just a reminder that all the brass looking metal things on our boats below the waterline (rudder, prop, sea cocks, etc.) are not brass! They’re all bronze - or at least they should be bronze. There’s a difference between brass and bronze in terms of seawater corrosion resistance. Not everyone understands the difference - I’ve even received e-mails from FM customer support calling the prop material to be brass.
I was looking for a spare garboard drain plug for my boat last week. A well known big marine chain tried to sell me a brass plug. The garboard flange fitting is bronze. Not a good idea to mix metals and not a good application for brass. Finally we settled on a more expensive bronze plug.
So, if you are looking to replace below the waterline metal fittings, go with 316 stainless (if it’s not touching anything else metal) or bronze but not brass….

PS: Don’t buy this one https://www.westmarine.com/west-marine- ... uMEALw_wcB

Groco makes an all bronze garboard fitting, might get a spare plug from them. Yes, I went through several "bronze" fittings that turned out to be brass. Not sure, but close look at the original king marine fitting appears to have brass plug

Bronze is cast in sand and will have a rougher appearance than polished brass. Easy way to tell them apart.

Fluid Motion should take a bit of this advice... there is a BRASS hose tee in the raw water line between the engine and the transmission oil cooler that feeds the shaft packing. It's made of brass, and it's starting to corrode badly on my 2016 C30. Another friend on here has a C30, and his failed. Thankfully the part is readily available and it's an easy enough fix to swap it out, but it's still brass so will eventually fail again...

I found the following in stainless steel that should work

https://www.xtremediesel.com/ppe-119020 ... d_source=1

I just purchased one, and will source a 1/4 npt to 3/8 barb locally since those aren't very special. I'll report back.

The part from xtremediesel is working perfectly.

The required barb for the shaft cooling hose is 1/4 inch, not 3/8, so get a 1/4 inch npt to 1/4 inch barb. I had to buy another after mixing that up.

Here is the old brass one
https://www.icloud.com/sharedalbum/#B14 ... F3FC2C88BB