Leak?

[samgx]

Hello all,
I purchased a 98 Honda Civic a couple of weeks ago from a used car lot that sells NGVs on a regular basis. The car is in decent shape for a '98. I bought it with 83,000 miles, and the tank does not expire until 2013 -- something I learned after being on this forum. Well, the only thing that's been problematic is a slight odor I get from time to time that smell like NG. When I brought this problem up to the attention of the seller, he recommended I take it to Scott Robinson Honda in Torrance, CA, as they specialize on Civic GXs. The first time I took it, it passed thier 110 point inspection. However, I did not receive a the CNG inspector's report that is mentioned on some of the treads. It was only after the 3rd time I took it for the same problem did I request the report. I was happy to receive the report with no problems. The car passed all tests with no problems -- no leaks. It was definately piece of mind for me. However, I continue to get the occasional smell here and there, especially after it's been parked a while or overnight, not to mention multiple nights (weekends). So, has anyone else had this problem? And, how did you end up resolving it? Is it normal to get the occasional smell? Any leads will be greatly appreciated!

Thanks,
Samgx

[Highmarker]

Re: Leak?

Samgx,

Honda used Type IV tanks in the Civic GX up until '01 or '02 (can remember when they switched to Type III tanks). Type IV tanks are plastic lined with carbon fiber wrappings. Type III tanks are aluminum lined with carbon fiber wrappings. Natural gas "permeates" (or seeps) through the plastic liner and the carbon fiber wrappings. The permeation rate is normal on all Type IV tanks. The rate of permeation is tested and approved prior to the design of the tank being certified. Type III tanks (metal lined with carbon fiber composite wrappings) do not permeate because aluminum has superior impermeability properties with natural gas. This is one of the reasons why Honda changed from Type IV tanks to Type III tanks. Hope this answers your question.

[samgx]

Re: Leak?

Thanks, Jared. It does answer my question. You would figure that the Honda CNG techs would know this -- he did mentiond that a lot of GX owners complain about NG odors. Do you know where I may find this information posted? So, from what it sounds like, if I want to get completely rid of this slight odor, I would have to change to a Type III Tank? If so, how much do these tanks costs? And, do you know of any companies in the Southern California area that I could purchase the tank from and who would actually handle the installation?

Thanks again for your help.

[Johnlaroux]

Re: Leak?

Ive never smelled gas in my 99 civic. Maybe you have a leak on your tank like the guy in this thread. http://www.cngchat.com/forum/showthr...hlight=bubbles

[jetboatjohnny]

Re: Leak?

I never had an odor in my '99 or my 2009.

[samgx]

Re: Leak?

Thanks for the replies. The CNG techs checked the entire system from the tank to the motor with a bubble making substance but couldn't find any leaks. I'll check myself, especially this area, just to be on the safe side.

Thanks,
Samgx

[freedml]

Re: Leak?

An occasional whiff of Mercaptan (the odor in NG) is not all that unusual.

[samgx]

Re: Leak?

I'll keep that in mind, Freedml. I started dismantling my GX (metal barrier and back seat) and started soaping all of the fittings and realized none of them were actually pressurized hoses - lol. I realize that I have to take all of the rubber fittings off to get to the actual pressurized parts. This will be a weekender for me! I'm going to fill up the tank, just like the member on the forum did, to see if it makes it easier to locate. Keep the replies coming....

For those of you who have already replied, thank you!

[Amfuel]

Re: Leak?

The big box home stores have electronic sniiffers for about $25 now. A better solution than bubbles. I went with a sniffer years ago when I missed the back side of a part and got called back. The sniffer will squeel when in the presence of a conbustible gas and increase as you near the leak. (mine is older and I paid more but that is what was available then)

[larrycng]

Re: Leak?

As has been said, the use of leak detection fluid is probably the best way to find seepage in a Lincoln tank, in my opinion.

I would suggest you fill the tank, remove the back seat and the shielding in the trunk (to gain total access to the tank), and then spray the whole tank with leak detector fluid and look for leaks. You might want to put a towel under the tank to catche any drips. If there are no bubbles you are good to go. If there are bubbles, you need to determine what gas (air or methane) is causing the bubbles, for this you will good methane detector.

This should rule out the tank as a source of leaks. Honda has done a good job of sealing the cng system inside the vehicle. If you do get a good electronic detector, and last one I bought was about $175, check the vent tube next to the fill nozzle and see if the electronic detector goes off. This is the upper end of the "vent bag" system that covers the tank valve and Joint block that sits under the back seat. If methane is detected, then the rubber covers need to be removed as you indicate. I'd to the tank first.

Hope this helps

Larrycng

[samgx]

Re: Leak?

Thanks for the suggestions. I'll keep you posted on my results.

[samgx]

Re: Leak?

Hello all,
I just wanted to give everyone a quick update. I inspected the tank as suggested by Larrycng, and inspected the fuel line fittings that connect to the cylinder as the member in this thread did: http://www.cngchat.com/forum/showthr...hlight=bubbles. I was happy to see that no air bubbles were forming in any of the areas mentioned. However, since I'm not a certified CNG Inspector, I still wasn't at ease -- I could've been doing something wrong. So, I decided to run it through one more inspection. I took it to Mario at CNGCARS/LA and am happy to report that he did not find any leaks. He did a thorough inspection of the cylinder, fuel lines, and fuel line fittings. He even checked the connections by the FPR -- Thanks, Mario. I'm confident now -- after 4 inspections -- that the fuel system is free of leaks. I came to the conclusion that the slight odor is from normal causes as mentioned by of the members, or it's all in my head as my wife tells me.

Thanks again to those who responded with the possible causes and suggestions.

Sam

[300mileclub]

Rebellion Photonics' hyperspectral video camera can "see" gas leaks

U-JIN LEE | CBS NEWS | 4 March 2015 - A technology to detect gas leaks in the air using a special hyperspectral video camera developed by optical engineer Robert Kester has been commercialized in a company he and Allison Lami Sawyer have founded, called Rebellion Photonics. The camera can immediately spot leaks in oilfields and refineries, and even determine the type of gas that's being emitted.

. . . While studying cancer in pursuit of a Ph.D. in bioengineering at Rice University, Kester invented a hyperspectral camera that attached to a microscope and could take pictures of cells at 30 frames per second. The device could "see" chemicals, allowing researchers to shoot live video of cancer cells to determine whether they were malignant or benign . . .

“Once I developed a new way to do hyperspectral imaging, I knew I wanted to start my own company based on this invention," Kester said . . . Rebellion Photonics was formed in 2010 to sell systems for biomedical applications . . .

Hyperspectral imaging is a way to visualize wavelengths in the electromagnetic spectrum that are outside the range of what the human eye can see. Different minerals and gasses each have their own spectral fingerprint, what Kester likened to a barcode. Hyperspectral cameras are able to read these unique bar codes and represent each one as a color. Typically these colors would appear in a static image, but Kester's camera could do the same thing in video, and in real time.

After months of research and experimentation, he figured out how to harness the technology for wide-field imaging, like across oilfields. Ultimately he came up with the Gas Cloud Imaging camera that could sense a cloud of gas in the air and show it on a live video feed . . .

The standard detectors the petroleum industry uses for gas monitoring and detection only cover a small fraction of a rig or refinery, according to Kester. The gas fumes must touch the sensors before operators are alerted to their presence. His hyperspectral imaging camera represents a huge leap, seeing gas as it escapes from the source, long before it spreads far enough to reach a remote sensor . . .

Based in Houston, Texas, Rebellion Photonics now manufactures its cameras and sells its services as a monthly subscription to companies in the oil and gas industry, including giants such as BP, Chevron and Southwestern Energy. It also landed an $800,000 military contract to put its cameras on Air Force drones . . .

For its oil industry customers it offers a truck-mounted camera for upstream sites, where drilling and fracking occurs, and a fixed-installation camera at many downstream sites, where oil is refined.

One surprising -- and disturbing -- finding that seems to crop up again and again: Many gas leaks come from hatches that weren't closed properly.

"About 90 percent of the emissions we see are caused by human errors and are easily fixable," Sawyer said.

She found that at many of the oil and gas processing sites, dehydrators used to remove water from natural oil and gas -- specifically the ones built before 1990 -- were responsible for emitting tons of methane themselves . . .

http://www.cbsnews.com/news/worlds-first-hyperspectral-video-camera-detects-explosive-gas-leaks/