Propane leak or normal?

[IslanderWannaBe]

Hello all,
We recently bought a sailboat and it has a propane locker. The surveyor noted it had a propane leak since it would not hold pressure long. It crept down within a few mins after pressurizing and closing.

I have replaced the regulator and hoses in the propane locker. Did the pressure test and it holds for about an hour. I read that the uscg test is for 3-10 min it should hold. After about an hour it creeps down about 5 psi and then over night it will read zero psi.

I cannot find anything regarding if this is normal and has some sort of relief valve that lets it out or if it should hold indefinitely. The only thing I haven't replaced yet is the lpg solenoid and the interior hose to the stove.

I will be doing a soapy solution bubble test but was wondering if anyone has any experience with propane and holding pressure?

[donradcliffe]

It should hold better than that. My experience is losing 5 psi overnite. I think your system is probably safe, but I would definitely do the soap solution.

[boatpoker]

The system is unsafe, no propane leak is acceptable ..... period !

[senormechanico]

We have a gauge on our tank as well.
Some variation in pressure due to temperature is normal, but if it's lower in the morning, it rises back later in the day due to daytime heating.

[rwidman]

Originally Posted by boatpoker

The system is unsafe, no propane leak is acceptable ..... period !

That's the answer I'm going with.

[Lepke]

If the locker is outside the hull and is vented in such a way that the propane cannot get onto the hull you are probably ok. And If the are no leaks in the stove or lines. Propane is heavier than air and settles in low places like the engine room or bilge, waiting for a spark.
I don't use propane inside the hull, but here's a couple favorite pictures of propane in enclosed spaces....

[denverd0n]

Originally Posted by boatpoker

The system is unsafe, no propane leak is acceptable ..... period !

Absolutely!

Propane is a wonderful fuel that can be used safely if one is careful with it. Being laissez-faire about "just a little bit" of propane that is leaking and pooling in your bilges, though, is definitely neither "safe" nor "careful."

Find the leak and fix it!

Good luck.

[a64pilot]

Try this, see if leaving the solenoid open makes any difference, if it leaks faster with the solenoid open, then I'd suspect a small leak in the stove. If it makes no difference, first remove that tank, inspect the connections and maybe switch tanks, it could be the O ring on the connection itself.
Of course bubble test everything, I like to use a small soft paint brush with soapy water. You can of course just dribble the solution too, an eye dropper bottle or ear wash bottle is perfect.

Leaks start out small, and rarely don't get worse

You can test the stove by capping off the line, if the leaks disappears, then it's somewhere in the stove

[deblen]

Question:
Is the OP talking about his tank pressure gauge dropping after turning the tank valve off
or
he pressurized the propane locker box itself & the locker box is slowly leaking down.

Edit: On re reading OP post,I think the "it" is the tank,reg,gauge & piping.

Soapy sponge will find leak.Start with regulator where it screws into tank valve,& check every joint from there to appliance. (You may as well check the tank valve where it screws into bottle & the pop off valve while you're at it)
Always open the tank valve fully against it's stop-there is a "back seal"

/ Len

[a64pilot]

Originally Posted by IslanderWannaBe

It crept down within a few mins after pressurizing and closing.

He said after pressurizing and closing

[captmikem]

Originally Posted by Lepke

I don't use propane inside the hull, but here's a couple favorite pictures of propane in enclosed spaces....

Several years ago I was of the same opinion, but nearly every charter boat in the Caribbean uses propane, and I have seen charters do the most outlandish, unimaginable, and utterly stupid things with their boats. If it were unsafe you would see charter boats being blown up left and right, but you do not hear of any.

Therefore, IMHO it has to be safe.

Michael

[reed1v]

Originally Posted by donradcliffe

It should hold better than that. My experience is losing 5 psi overnite. I think your system is probably safe, but I would definitely do the soap solution.

You will kill someone with that type of advice. Propane is dangerous and can find its way into the bilge where it will accumulate till the boat explodes, assuming no sniffer, no sparkless vapor pumps.

No leak is the norm. None. Not sure if the OP means the locker which contains the canisters or the canisters. If its the locker, nothing makes sense. If the actual propane canisters, they need to be replaced if the valves have been seated properly(you did use teflon tape?). For thirty bucks why take the enormous risk of having propane vapors washing over the boat?

[reed1v]

Originally Posted by captmikem

Several years ago I was of the same opinion, but nearly every charter boat in the Caribbean uses propane, and I have seen charters do the most outlandish, unimaginable, and utterly stupid things with their boats. If it were unsafe you would see charter boats being blown up left and right, but you do not hear of any.

Therefore, IMHO it has to be safe.

Michael

They have blown up, caught fire, and have poisoned folks. We treated a bunch of cases throughout the windward islands back in the 90s. Do you have any experience with boats?

[reed1v]

For the clueless non sailors on this board, propane needs to be treated carefully. Even if its stored on deck, because its so heavy as a gas, any leaks can easily be blown down open hatches, through open port lights, and even down vent tubes. Think of it as an invisible water.
A lot of times we would be treating someone for violent seasickness only to find out they had been inhaling propane without knowing it. We use to carry sniffers as a routine tool around boats and found many had propane sitting in their bilges, within closed lockers, and within a closed anchor well. Regular inspection is essential. A propane system needs to be absolutely tight with zero emissions of propane under any and all conditions except for the purpose for which it was intended.

[artisanmach]

I have two aluminum propane tanks. one of them leaks down within five minutes, the other does not leak at all. it turned out to be the valve stem. it leaks what is in the system in the closed position. I agree NO leak is okay on a boat.