LPG locker filling with seawater

[MarkSF]

On a starboard tack it seems that my LPG bottle locker is filling with seawater. There is a drain/vent hose that connects the bottom of the locker to a hole on the stern, level with the engine exhaust.

The result is that both my bottles are completely rusted out at the base.

Could anyone suggest a fix?

[imagine2frolic]

Raise the hose higher than the thruhull, and put an anti siphon valve in it.....i2f

[MarkSF]

Originally Posted by imagine2frolic

Raise the hose higher than the thruhull, and put an anti siphon valve in it.....i2f

Wouldn't that stop any leaking LPG from running down the hose?

[djodenda]

When you replace your tanks, go with fiberglass. I really like my fiberglass tanks.

Not trying to be a wise-acre. And I don't have a fix for your problem, although the fiberglass tanks won't mind getting wet.

[PorFin]

Originally Posted by MarkSF

On a starboard tack it seems that my LPG bottle locker is filling with seawater. There is a drain/vent hose that connects the bottom of the locker to a hole on the stern, level with the engine exhaust.

The result is that both my bottles are completely rusted out at the base.

Could anyone suggest a fix?

Rerouting the vent line sounds in order, but may be tricky depending on your hull design. The danger (as you've touched on) is getting propane trapped in the line when the through hull is buried and water effectively blocks the passage.

A no cost option would be to not heel the boat over so far on a starboard tack.

While not addressing the cause, since you've got to replace the tanks anyway replace them with composite tanks (best) or aluminum (better than steel.)

Hope you find a good solution.

[Hartley18]

Gas bottles really should be elevated slightly above the floor of the locker on a low plastic/fibreglass plinth, away from the water getting in (presumably only a small amount). Stainless steel tanks are available in some places but do tend to be a little expensive..

You can probably install a flapper valve (piece of plastic on a hinge over the outside of the vent hole) that will allow stuff out but very little back in. That, plus the low plinth, should be enough to stop your tanks rusting out.

[MarkSF]

The bottom of the locker does have some raised ribbing, but I'm wondering if it's high enough. Maybe there's vertical room to raise the bottles an inch or two higher.

The fibreglass bottle sounds like a good solution. As I only do weekend sails, I'm thinking of going with just one bottle and a single regulator and saving some money. I can always add a second one later.

[mitiempo]

The vent hose has to travel downhill to the through hull. If it is re-routed upwards, whether there is an anti siphon or not, it will not drain.

[MarkSF]

Originally Posted by mitiempo

The vent hose has to travel downhill to the through hull. If it is re-routed upwards, whether there is an anti siphon or not, it will not drain.

Yes, I agree that's not a solution. It's not really a hose either, it's a solid fibreglassed tube! Typical Bristol over-engineering.

[Hartley18]

Originally Posted by MarkSF

The bottom of the locker does have some raised ribbing, but I'm wondering if it's high enough. Maybe there's vertical room to raise the bottles an inch or two higher.

Mark, it doesn't need to be higher than an inch. Just enough to allow whatever water does leak in via the flapper valve (usually less than a half-cupful) to not reach the skin of the tank.

It does sound to me like a flapper valve on the vent is all you really need.