Hi all,
Need to replace my head's seized ball valve, wonder would it be wise to take this opportunity to replace all others (quite stiff too).
I have 7 holes underwater line in my boat;
2 for engines (mercury 1 1/4" water pickup valve)
1 for the genny (apollo 3/4" bronze ball valve mounted onto a groco triangle flanged adapter).
1 for the aircond (apollo 3/4" bronze ball valve mounted directly on the mushroom head thruhull fitting).
1 for the head (apollo 3/4" bronze ball valve mounted directly on the mushroom head thruhull fitting).
2 for transducers.
None of these holes has a "backing plate" glassed, all thruhull fittings are screwed directly onto the bare fibreglass hull. errh... look a bit fragile !
And the aircond and head setups are female NPT ball valves whereas the thruhull fittings are male NPS, thus mismatch thread.
Note that these setup are original from the manufacturer.
Read a lot of articles concerning thruhull fittings, for safety, most of them advocate for "backing plates" and prohibit "mismatch thread" setup.
So my questions:
1): Is it an exaggeration or is it a real potentiality of danger for the setups I currently have ?
2): All my current Apollo ball valves are rated 600 psig (WOG), and I would like to replace by a much cheaper Groco 400 psig (WOG), will it be ok ?
If not mistaken, the pressure under water is measured by the total weight spread across the entire surface of the boat + the depth of the hull under water.
This is to exert only a pressure of a few psi. So why an overkill 600 psig valve needed? Am I missing something here ?
Appreciate any advice from you.
Thks
Need to replace my head's seized ball valve, wonder would it be wise to take this opportunity to replace all others (quite stiff too).
I have 7 holes underwater line in my boat;
2 for engines (mercury 1 1/4" water pickup valve)
1 for the genny (apollo 3/4" bronze ball valve mounted onto a groco triangle flanged adapter).
1 for the aircond (apollo 3/4" bronze ball valve mounted directly on the mushroom head thruhull fitting).
1 for the head (apollo 3/4" bronze ball valve mounted directly on the mushroom head thruhull fitting).
2 for transducers.
None of these holes has a "backing plate" glassed, all thruhull fittings are screwed directly onto the bare fibreglass hull. errh... look a bit fragile !
And the aircond and head setups are female NPT ball valves whereas the thruhull fittings are male NPS, thus mismatch thread.
Note that these setup are original from the manufacturer.
Read a lot of articles concerning thruhull fittings, for safety, most of them advocate for "backing plates" and prohibit "mismatch thread" setup.
So my questions:
1): Is it an exaggeration or is it a real potentiality of danger for the setups I currently have ?
2): All my current Apollo ball valves are rated 600 psig (WOG), and I would like to replace by a much cheaper Groco 400 psig (WOG), will it be ok ?
If not mistaken, the pressure under water is measured by the total weight spread across the entire surface of the boat + the depth of the hull under water.
This is to exert only a pressure of a few psi. So why an overkill 600 psig valve needed? Am I missing something here ?
Appreciate any advice from you.
Thks
