Through Hulls & Valves - 2007 Bavaria 42 Cruiser

[Aloha Spirit]

I'm trying to replace the ball valves for the head intake (3/4") and discharge (1 1/2").  The discharge valve as seized and in very bad shape (I broke the gooseneck off while trying to remove the hose).  The through hulls look OK, but I'm concerned they are "DZR" brass.  I tried to contact Bavaria but have not heard back from them confirming what the material is.  Can anyone confirm the material and have any advice on which way I should go with this.  I was going to install Grocko bronze ball valves but unless I can confirm material, I am now thinking of biting the bullet and replacing the through hulls with Grocko bronze as well so I'm certain I will not have any issues.  Any input would be much appreciated. 
Joe

[Krumelur]

My boat's valves are all pretty new but I know one thing for sure: any valve I need to replace will be "plastic".
I heard so many good things about "Trudesign" valves that I'm sold on them. You can also search the forum and will likely find many reference.

[tiger79]

The through-hulls will be DZR.  Best to replace them.

[symphony2]

Replace everything with DZR if you can get it. As the name implies although it is termed a "brass" the additives to the alloy make it dezincification resistant and equally as good as Grocko or any other "bronze". Generally cheaper as well. As suggested many are changing to non metallic through hulls and valves. Tru design are almost direct replacements but the bodies are larger which does sometimes give installation problems.

As you have discovered it is the end fittings - hose tails in particular that fail through dezincification rather than the valves. This is because they are often plain brass even when the valves are bronze or DZR. So essential to change everything and make sure all the fittings are DZR or bronze.

I note you are in the US and not sure DZR is readily available there as it was a UK developed alloy to cope with our domestic water supply, but now they are mostly made in Italy and are very high quality. The well known Blakes toilet valves have been DZR for nearly 40 years but unfortunately they are a different design and not direct replacements.

[Aloha Spirit]

Thanks for everyone's quick replies.  Yes, I'm in the US and the DZR are harder to get (as are the Trudesign non-metallic option).  The only good, readily available, options here in the states are Grocko bronze or the Forespar Marelon fittings.  I'd consider the Marelon (as I did on my old Dehler Optimo 101 when I refitted her years ago), but they are bulky and will make the fit a lot harder.  From all the responses and additional research, I'm convinced the way to go at this point is replacing the through hulls with Grocko bronze so they are all similar metal and compatible.  The Grocko's are well made, and the larger sized valves (1 1/2" and up) come with Zerk fittings so you can lubricate on regular basis.  Was hoping to avoid replacing the through hulls, but now that I'm this far it would be foolish to stop half way. 

One other question, has anyone had any issues removing the 1 1/2" valves at the bottom of the holding tank.  One of those are seized too, but I'm fearing I may mess up the plastic tank while trying to remove that valve, and then I'm REALLY in for a world of hurt. 

[Aloha Spirit]

Update & Another Question - So I ended up finding a US distributor for the True Design products and went that route - (Gemlux out of FL for those here in the states that may be interested - super helpful and fast free shipping  https://gemlux.com/).   As I went further down rabbit hole I decided to replace the 1 1/2" valves that come out of the holding tanks as they vary in condition and if I'm in this deep, I'm going all the way.  I'm going to have to buy skin fittings and cut off end as the tanks have female openings.  Does anyone know if they are threaded BSP or NPS.  I want to order correct fittings & valves.  Thanks

[nightowle]

THanks for the hook up on Gemlux.  I'm here in Seattle and Marelon would've been my only non bronze choice otherwise.  I'm ready to replace at least the engine raw water intake sea cock soon.

[Aloha Spirit]

Nightowle, another heads up.  If you need to replace valves coming out of holding tank, they are going to be BSP thread, not NPS.  Gemlux only stocks the NPS.  They would special order the BSP if you need it, but would take a while.  I was in a hurry as I had everything ripped apart and was rushing to meet a splash date.  I ended up finding a chandlery in UK that stocked the BSP parts.  Although I had to pay $57 in shipping, it came DHL air in a couple of days, AND, the parts were way cheaper than Gemlux so I actually saved a bit of money.   Here's their link if you need it.  https://www.oceanchandlery.com/
Good luck.