CNG tank refill

[Mcshane]

Have a new CNG refill station in town....finally. Has anyone removed their tank and had it refilled? I'm hoping it's as easy as a propane tank, but that's why I'm asking, I've never done it. Boat is on the hard waiting for launch in a month or so and thought I'd take care of this while it's on a cradle. Looks as though I unstrap it, use wrench and disconnect fitting. I'll also ask the New CNG filling company and see what they say. Don't want to make any mistakes with compressed natural gas. Thanks for any advise.

McShane

 

[Stu Jackson]

http://www.c34.org/wiki/index.php?title=CNG_Refill_Adapter

 

[Stretch]

Thx times 2

 

[Mcshane]

Thanks

http://www.c34.org/wiki/index.php?title=CNG_Refill_Adapter

Great diagram.

Thanks for the great diagram. I did receive the large brass end fitting from the original owner, so need the other parts. I'll show this diagram to the CNG filling station and make up one. Appreciate the help.

 

[wufibugs]

The City of Chula Vista, CA operates a fill station for its flleet, which is also open to the public. I wonder if I will need to build the adaptor for them to fill my tank. . . . hmm.

 

[psharkey1621]

Yes, removing and filling the tank is that easy. But not so fast.

The CNG tank is identical to that of a scuba tank with the exception of the threads in the tank due to a different valve assembly.

Any tank that holds compressed gas must be hydrostatic tested every 5 years or prior to refill if longer than 5 years.

These tanks hold gas at pressures of 2,250 psi. That equals about 80 cubic feet if gas in volume.

Check the top of the tank near the neck. The stamping on the tank should show the month and year of the last test.

I have a '85 S2, 9.2C. My CNG tank still has 550 psi in it. The stamping is the original stamping from the factory. My tank will need a visual and hydrostatic test prior to being filled again.

Check with your local scuba dive shop for a hydro test. It should only cost $20 or $30 bucks.

If it passes both tests, you're good to go on a refill. If not, your tank is junk scrap metal and must be replaced.

The good news is, very infrequently does a steel tank fail a hydro test.

Usually when that happens, the tank is extremely old and has been exposed to the elements for a long time.

Replacement of the tank is difficult in that "CNG" tanks are not easy to locate.

Your CNG fill station and dive shop can help you with testing, filling and replacing the tank if necessary.

Good luck.

Pat
Oinkers Aweigh
'85 S2 9.2C
Bay City, MI

 

[wufibugs]

Thanks, Sharkey. That probably saved me a useless trip to the refill station. Will find a local dive shop to run the test and update "cert" on the tank before filling.

 

[sailcruiser]

Should a replacement tank be needed this is a bookmark I have. I have NOT ordered one but would be a second stop after the classifieds.

http://www.corpbrothers.com/ma0502/item/4005-40084.php

SC

 

[fruivita]

Not to detour the thread but has anyone explored converting from CNG to LPG? It's far more available although I realize more dangerous being heavier than air.

 

[Alan Gomes]

You can find additional tanks at Minney's in Newport Beach, CA. I was there 2 weeks ago and saw some.

 

[psharkey1621]

Yes, removing and filling the tank is that easy. But not so fast.

The CNG tank is identical to that of a scuba tank with the exception of the threads in the tank due to a different valve assembly.

Any tank that holds compressed gas must be hydrostatic tested every 5 years or prior to refill if longer than 5 years.

These tanks hold gas at pressures of 2,250 psi. That equals about 80 cubic feet if gas in volume.

Check the top of the tank near the neck. The stamping on the tank should show the month and year of the last test.

I have a '85 S2, 9.2C. My CNG tank still has 550 psi in it. The stamping is the original stamping from the factory. My tank will need a visual and hydrostatic test prior to being filled again.

Check with your local scuba dive shop for a hydro test. It should only cost $20 or $30 bucks.

If it passes both tests, you're good to go on a refill. If not, your tank is junk scrap metal and must be replaced.

The good news is, very infrequently does a steel tank fail a hydro test.

Usually when that happens, the tank is extremely old and has been exposed to the elements for a long time.

Replacement of the tank is difficult in that "CNG" tanks are not easy to locate.

Your CNG fill station and dive shop can help you with testing, filling and replacing the tank if necessary.

Good luck.

Pat
Oinkers Aweigh
'85 S2 9.2C
Bay City, MI

FYI...
my CNG tank just passed a hydro test. I will be picking it up tomorrow from my local dive shop and driving to Blue Water Transit in Port Huron, Michigan for a refill. I will keep the site posted on the costs...
P Sharkey
Oinkers Aweigh
Busy City, MI

 

[psharkey1621]

FYI...
my CNG tank just passed a hydro test. I will be picking it up tomorrow from my local dive shop and driving to Blue Water Transit in Port Huron, Michigan for a refill. I will keep the site posted on the costs...
P Sharkey
Oinkers Aweigh
Busy City, MI

CNG Tank Refill UPDATE:
If anyone is in the Port Huron, MI area, the location to get your tank refilled is Yale Heating & Air.

Blue Water Transit can't fill the tanks due to the pressure difference. Their system will blow the pressure relief valve.

Cost for a tank refill is $45 for an 80 cubic foot volume tank.

Yale Heating & Air has a set up so they can fill multiple tanks at the same time. Only takes 15 to 20 minutes.

Good Luck on your filling station.

P Sharkey
1985 S2 9.2C
Oinkers Aweigh
Bay City, MI

 

[neilandsam]

We have the CNG and are in Canada and the only refil station is a two hour drive away..so we now have four tanks so that we can fill at the beginning of the season and not worry. But the CNG does seem to go a little faster than propane..especially when using the oven. It is easy to fill though..just like a propane tank. But you may want to have a spare tank on hand. Our sailing season is a short 4 - 5 months and for the past two years we have used almost 3 tanks each summer. I do not use the oven much because of how much gas it uses though..so we are glad to ahve a fourth tank now. the tanks will have to be certified to fill however so if they are past the fill date you will need to have the valves replaced like on a propane tank. but cheaper than a new tank.

 

[neilandsam]

We explored to great extents the conversion and after a ton of research have learned that it appears the parts needed to convert the stove are no longer available. The stove is in great shape...is on an '84 36 CC. So unless you are able to find a conversin kit it seems as if it cannot be done.