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Concordia 33
09-18-2007, 11:13 AM
Does anyone have a reference for the requirements for installing a an LPG or CNG tank in an older boat. I heard that the Coast Guard now requires CNG to meet the same standards as LPG, but having not see the regs on either, I am not sure what is involved. I have heard that for LPG, the tank must be enclosed and separate from the engine - futhermore, it must have some kind of vening in the bottom of the enclosure that temiates outside the hull so that the heavier-than-air gasses can escape without risk of explosion.

Can anone help me out with this information?

Thanks

Dale Genther
09-18-2007, 11:24 AM
I'm not familiar with the CNG regs, but am familiar with the LP regs. The ABYC lays them out pretty well. I just went thru them when decieding what type of stove to put on my 1955 S&S Gulfstream. The conclusion I came to is that to retrofit an older boat to accept LP is pretty difficult. Fo instance the lid should not (with certain exceptions) open into the inside of the boat. You are correct about a vent at the bottom.This usually means the best approach is to mount the tank in a box on deck unless you want to start cutting up your deck and/or cockpit lockers. This is what I had done on my previous boat. For the S&S I went with an Origo pressureless alochol 2 burner stove with oven. I have been very happy with this stove and the installation is easy.

Jay Greer
09-18-2007, 11:37 AM
Currently regs for installing CNG seem to be less specific than those for LPG. I am planning to intall a Force Ten CNG stove in my H28 "Bright Star" due to the fact that the tanks can be stored in a less conspicuous area than that of a propane set up. I do know that the same valving and piping saftey regs apply to both sysems.
Jay

Dale Genther
09-18-2007, 11:38 AM
One thing I forgot. What I do know about CNG is that the gas can be difficult to get, especially in remote areas. Here in the Rock Hall area we have a couple of thousand pleasure boats and at least a dozen large marins. You can get CNG cylinders exchanged at only one place.

Concordia 33
09-18-2007, 11:57 AM
Thanks for the information, this is helpful. I heard that CNG is more difficult to get. Is there a specific reference I can find that states the installation requirements. Some of the coast guard regs refernced also mention that these rules do not apply to vessels that accomodate 6 or fewer people. Also the regs seem to reference "Passeger" vessels, so I couldn't tell if that meant they were for were referring to vessels for hire or simply differentiating between vessels carrying cargo. Any insights would be helpful. I have a stern cockpit locker, that might be able to be modified into a storage place, but I definitely do not want to have a box on deck, it will destroy the historic and aestheticlook of the boat.

donald branscom
09-18-2007, 01:54 PM
Does anyone have a reference for the requirements for installing a an LPG or CNG tank in an older boat. I heard that the Coast Guard now requires CNG to meet the same standards as LPG, but having not see the regs on either, I am not sure what is involved. I have heard that for LPG, the tank must be enclosed and separate from the engine - futhermore, it must have some kind of vening in the bottom of the enclosure that temiates outside the hull so that the heavier-than-air gasses can escape without risk of explosion.

Can anone help me out with this information?

Thanks
The age of the boat does not matter.
What is so hard about a box with a vent in the bottom?
Just do it. Or put an aluminum tank on the stern railing.
But use LPG.(heavier than air) It is easier to get at every port.

Your cockpit lockers should NOT lead to the inside of the boat anyway. Bad idea. A lot of cheap boats are built like that. Easily remidied.

Also use a flexable hose and have the least amount of connections possible. I put the hose inside of a pvc tube clamped to the hull or joinery work to protect it.
By the way skip those stupid electric switches and all that mess.
The switches get corroded then you have no safety. Just turn the tank on when you are using it and turn the tank valve off when you leave the boat. Just that simple. If you think you will forget to turn off the propane tank put a reminder on the railing exit or something.
But if you are that forgetful should you be sailing at all?

But if all of it scares you . Just buy a little portable unit, (little portable cannister of gas) and take it onboard with you and take it with you when you leave. DONE.

I was a live aboard for 15 years and the best way is the simple way.
The ONLY accident I ever saw in 15 years was when a man almost 80 years old living on his boat and shouldn't have been, did not take care of his boat or his tanks which were just sitting inside the boat.
He lit the stove ,there was an explosion and he ended up on the dock with no injuries, The whole deck was blown off because it was attached with screws that were too short. (saving grace) I went and looked in the boat thru the 4 inch seperation of deck and hull and the inside of the boat looked like a rat had been living there for 10 years. The propane tanks were completely rusted. The old man recovered and was ok but was not allowed on the boat anymore for his and his neighbors safety.

Lew Barrett
09-18-2007, 02:20 PM
http://www.imagestation.com/picture/sraid197/p34263a9e7838cf6a2b458082f3b32e4a/f10d3017.jpg
Where is the LPG tank on this boat? Look closely because it's hidden in the clear.

Concordia 33
09-18-2007, 02:22 PM
The age of the boat does not matter.
What is so hard about a box with a vent in the bottom?
Just do it. Or put an aluminum tank on the stern railing.
But use LPG.(heavier than air) It is easier to get at every port.

Your cockpit lockers should NOT lead to the inside of the boat anyway. Bad idea. A lot of cheap boats are built like that. Easily remidied.

Also use a flexable hose and have the least amount of connections possible. I put the hose inside of a pvc tube clamped to the hull or joinery work to protect it.
By the way skip those stupid electric switches and all that mess.
The switches get corroded then you have no safety. Just turn the tank on when you are using it and turn the tank valve off when you leave the boat. Just that simple. If you think you will forget to turn off the propane tank put a reminder on the railing exit or something.
But if you are that forgetful should you be sailing at all?

But if all of it scares you . Just buy a little portable unit, (little portable cannister of gas) and take it onboard with you and take it with you when you leave. DONE.

I was a live aboard for 15 years and the best way is the simple way.
The ONLY accident I ever saw in 15 years was when a man almost 80 years old living on his boat and shouldn't have been, did not take care of his boat or his tanks which were just sitting inside the boat.
He lit the stove ,there was an explosion and he ended up on the dock with no injuries, The whole deck was blown off because it was attached with screws that were too short. (saving grace) I went and looked in the boat thru the 4 inch seperation of deck and hull and the inside of the boat looked like a rat had been living there for 10 years. The propane tanks were completely rusted. The old man recovered and was ok but was not allowed on the boat anymore for his and his neighbors safety.
Thanks for your wisdom on this

Dale Genther
09-18-2007, 03:56 PM
Concordia

Here is are some of the ABYC requirements concerning propane lockers:

-Cylinder shall be located in a ventilated location on the exterior of the boat where excaping gases will flow directly overboard, or

-If the escaping vapors will not flow directly overboard, the cylinder shall be installed in a dedicated locker meeting the following requirements. Lockers shall be:

--Vapor tight to the interior of the boat
--Located above the waterline
--Constructed of corrosion resistant materials
--Shall open only from the top
--Shall have a gasketed lid and shall latch tightly
--Shall be able to be opened quickly without the use of tools

- Lockers shall be installed so that the locker opens directly only to the outside atmosphere, and

-If a LPG locker is installed inside aboat locker, the LPG locker shall be located as high and as close to the boat locker's opening as possible

-Lockers shall be vented at the bottom by a vent, with a minimum inside diameter of 1/2 inches

-Locker vents shall be led outboard, without pockets, through the hull to a point lower than the locker bottom and above the waterline.

-Locker vents shall be located at least 20 inches from any hull opening to the boat's interior.

These are not all of the requirements for LPG lockers, just the ones the can sometimes be difficult to comply with in a retrofit situation. There are also other lists by ABYC of LPG requirements concerning ignition protection, cylinders, valves, safety devices, fuel lines, testing, and safety signs and labels.

If I were you I'd pay close attention to the ABYC requirements. It's not that with a reasonable degree of care you can't operate an LPG system that is out of compliance. There are many boats out there that have been doing just that for a long time with no problem. I am a member of ABYC and a part time surveyor, so I can tell you that if I'm requested to do a survey for the purpose of obtaining insurance and I find a safty related violation of ABYC, I will report that the boat is not a good insurance risk until that item is corrected. I would be remise in my responsibility if I did otherwise. On the other hand if I'm requested to consult as part of an insurance claim, and I can find enough pieces to determine that the cause of the problem was an improperly installed sytem (LPG or other), your insurance coverage may be at risk.

Donald,

Concerning your comment about cockpit lockers and not leading to the interior of the boat. I've owned a lot of wood boats. Some with very good names, such as Sparkman & Stevens, Dickerson, and German Frers Sr. While I agree with you in that it would be best if they did not open to the interior, on any boat I've ever owned they always did.

Chan
09-18-2007, 05:04 PM
The commercially available compliant propane lockers are verrry pricey.
$650 for a single $850 for double cylinder locker. Hamilton Marine.

Lew Barrett
09-18-2007, 06:31 PM
You can mount a small tank on the cabin roof, make a canvas cover for it in a color of your choice, and plumb per Donald's recommendations. Have you located the tank on Rita yet?

donald branscom
09-18-2007, 11:08 PM
Concordia

Here is are some of the ABYC requirements concerning propane lockers:

-Cylinder shall be located in a ventilated location on the exterior of the boat where excaping gases will flow directly overboard, or......(shortened to save space)

Donald,

Concerning your comment about cockpit lockers and not leading to the interior of the boat. I've owned a lot of wood boats. Some with very good names, such as Sparkman & Stevens, Dickerson, and German Frers Sr. While I agree with you in that it would be best if they did not open to the interior, on any boat I've ever owned they always did.

Big names don't scare me. I would still make an insert for those lockers. I have heard of at least one boat lost at sea when a wave swamped the boat, then the engine would not start. then more water came in thru the cockpit lockers and finally the crew had to abndon ship. They pulled the cord for the $5,000 dollar raft to auto inflate which it did and then the wind blew it away .Finally they used a hard dingy to escape.

donald branscom
09-18-2007, 11:12 PM
The commercially available compliant propane lockers are verrry pricey.
$650 for a single $850 for double cylinder locker. Hamilton Marine.

Chan,

Do not buy from the marine store. Instead buy the locker from an RV store, much cheaper. Also many things are available from snowmobile catalogues and camping catalogue's. Same item just a reasonable price, Check it out and you will see. Only buy from a marine store when there is no other way. Just like stainless bolts and nuts, I buy them from hot rod websites MUCH CHEAPER. They would never pay marine prices. They have families to feed.

donald branscom
09-18-2007, 11:22 PM
One more thing about propane.The tanks have a date stamped on them. that is the date they need hydro testing. Every 12 years.
So be careful buying 2nd hand. Check the date.
If checking an olld tank look at the bottom for rust .

Also if you buy an aluminum tank check the weld around the middle of the tank where the weld stops and starts. Welding positioners do this but someone has to make sure the stop and start does not have a crater. The crater can leak.The stop and start is gone over by hand. I know i had one that leaked from the weld. It was a new tank. Good welding machines have a crater fill function but now that manufacturing, machines and good employees have been lost you will see a lot of lousy workmanship.

donald branscom
09-18-2007, 11:29 PM
http://www.imagestation.com/picture/sraid197/p34263a9e7838cf6a2b458082f3b32e4a/f10d3017.jpg
Where is the LPG tank on this boat? Look closely because it's hidden in the clear.

Very good Lew ! Funny how any thing covered with blue canvas all of a sudden looks very "marine" and ship shape.

NealmCarter
09-19-2007, 05:06 AM
Concordia, We are installing CNG on ~Elf~, an 1888 Lawley. The USCG and several marine museums ...All recommend CNG over the use of LPG. We are deck mounting our bottle, as its the safest method of installation. Also in your area, CNG is available.

Concordia 33
09-20-2007, 02:33 PM
Everybody's ideas and suggestions are very helpful. I'm exploring building a space in the stern for a propane locker. If that doesn't work, I'll explore other options, possibly building a mahogany box on the trunk top an putting a small horizontal cylinder inside it.

Thanks

donald branscom
09-20-2007, 08:06 PM
Everybody's ideas and suggestions are very helpful. I'm exploring building a space in the stern for a propane locker. If that doesn't work, I'll explore other options, possibly building a mahogany box on the trunk top an putting a small horizontal cylinder inside it.

Thanks
I like the box idea. sounds nice. and you could store the wrench in there too.

maa. melee
09-20-2007, 09:00 PM
Get yourself an old oak rum or whiskey barrel and remove the lid. A wine barrel would be too big. Drop the tank inside, open a vent at the base and run your lines. Viola, instant gratification.

Lew Barrett
09-21-2007, 12:10 AM
Funny. I like the canvas. Simple, disappears on the boat, just sew it up and put on the snaps, lowest possible profile and guaranteed to let everything leak out the bottom. I intended to do a teak box and a friend made the cover for me and said "Here, try this." My friend Charlie designed a little teak cleating system for the can (happy to share it if you'd like...it's slick) and I've never looked back. In 14 years nobody has ever said to me "what's the canvas for." Of course they haven't; it passes any detection.

davidagage
09-21-2007, 08:51 AM
psssst Lew...((Concordia 33 isn't Margo....she's concordia...41);)

PS Love the canvass covers, a great way to go!

Lew Barrett
09-21-2007, 09:53 AM
psssst Lew...((Concordia 33 isn't Margo....she's concordia...41);)

PS Love the canvass covers, a great way to go!

David,
There's this awful thing that happened to me when I passed 60.....
All posts corrected for lunacy........

Concordia...41
09-21-2007, 10:07 AM
It's OK, I was kinda looking forward to less boat to paint and sand today ;):p

Dan McCosh
09-21-2007, 10:52 AM
The deck box directly behind the mast is a propane tank cover. It doesn't have a bottom, sits on four legs for ventillation. It contains a 5 lb. tank, with some extra storage for tools, etc. A 10 lb. horizontal tank would be about the same size. http://i242.photobucket.com/albums/ff159/dmccosh/P1020585.jpg

Lew Barrett
09-21-2007, 01:01 PM
It's OK, I was kinda looking forward to less boat to paint and sand today ;):p

When you didn't respond to my carefully crafted posts, I thought "she doesn't love me anymore." And, I cried.

Concordia 33
09-21-2007, 02:09 PM
The deck box directly behind the mast is a propane tank cover. It doesn't have a bottom, sits on four legs for ventillation. It contains a 5 lb. tank, with some extra storage for tools, etc. A 10 lb. horizontal tank would be about the same size.


This photo really helps me see how it can nicely work in the open if need be.