Just went over some discussions on subject of seacock installation
. OK, those Trudesigns are ball valves, I get it. The question still is what do I use for sealing? There are 3 connections to make: a) the skin fitting aka thruhull to the hull
, b) thruhull to ball valve and c) ball valve to barb hose connector aka adaptor. The manufacturer recommends 5200 or 4200 or some other stuff which is no longer produced. For the a) I think 4200 will do, how about Sika 291? For the other two I'm reluctant to use 4200 because I feel it will be impossible to take apart if needed. I used RectorSeal Blue on HWPDE plastic black water
tank to seal threaded connections, seems working fine i.e. sealing out liquids while not getting rock hard. Furthermore, when 4200 is used, even if connection is taken apart, it will be impossible to clean out old sealant
and this feature is kind of useless. Being a "pipe dope" Rectorseal can probably be removed by a solvent and some parts
can be re-used.
Some Youtubers just used 5200 on all three connections.
Thanks in advance.