Afternoon all, I am replacing a couple of 27 yo gate valves that are on some thru hulls with quarter turn bronze ball valves and was wondering what if anything should I put on the threads when i screw on the valves ? also if I need to add any elbows or nipples, is it ok to use brass ones or do they have to be bronze as well? OK thanks ! ! ! AHHHhhhh got to love retired life aboard
Please involve a reliable surveyor on these matters. You CAN NOT insert brass with anything below the water line... Bonded bronze or Marelon only. Also NO pvc or un-reinforced plastics. It does send a shiver up my spine when people talk about brass below the water line. Do not listen to the Ace Hardware guy telling you it is O K to use. ,Ralph
Thread sealant is important also. You want a good metal to metal contact for bonding but need a leak proof sealant. Teflon tape has become a standard but I am feared it may not allow enough galvanic contact between the metals. I have used blue pipe dope but have not trusted anything and inspect often. I'm also well bonded and have no problems after many years. BUT, I keep inspecting and pulling on every piece often. Break it before it becomes a surprise at the wrong time is a good inspection attitude.
Brass is often used, unfortunately and some fittings are hard to find in pure bronze especially nipples. Big mistake... They will disintegrate in as little as a few months. If you re lucky, as I was one time, the failure will happen when you are cleaning that strainer... Unfortunate many so called professional technicians still use them
The OP says his location is Portland, Oregon - a freshwater port. If he operates continuously in fresh water there is little risk. Even if he goes out in the saltchuck from time to time there is little risk. The use of brass on a seawater system is not a promise of death or disaster. You might be surprised how many brass fitting and components you have on the salt water side of your boat that you don't even know about. Oh, as far as for what to put on the threads ... I like to use Rectorseal. It cleans up nicely with mineral spirits and seals very well.