2 questions CNG Smell + fill valve is "ball bearing" necessary?

[yepper]

Hi CNG Chat members - 2 questions: Would like to know your techniques in sniffing out a leak in a CNG system - bought 2000 Crown Victoria and had additional tanks (2002 CV tanks) installed in trunk by dealer in Utah, had car shipped to CA, and upon receiving - heavy CNG smell inside vehicle. Dealer has not responded with my concern. Other concern is the fill valve does not appear to have the "ball bearing" visible from outside...is that ball bearing critical? thank you in advance...

[afvman]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Yepper,

I'd worry more about the smell than the fill valve...unless that's where the smell is coming from!

I looked and the Ford fill valve prop I use during training classes and it doesn't appear to have a ball in the end, but there is one further back...trust me.

The smell is a whole other thing. You need to trace that down regardless of whether the dealer takes responsibility or not. Shouldn't be too hard. Your nose is a good start. A soap and water mix also works (I prefer Dove), but you need to find it and fix it.

Coupla' of pointers. If it's a fitting, don't think that tightening them some more is better. They need to be depressurized, disassembled, checked and remade properly. Remember the rule: "There's no such thing as a small leak! It either leaks or it doesn't. If it does, fix it." (Actually, I just made that up.)

Good luck and don't use Bic lighters!

afvman/Bill

[yepper]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Thanks Guru - I will start with the soapy water and trace back where the additional tank install was done by exposing the CNG lines from the tank. Any additional helpful hints are appreciated. I can email a pic of the trunk and install if that might help - thanks again

[afvman]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Yepper,

Yes, send pictures...

I'd like to see how they added tanks to a Crown Vic. It already had three or four from Ford!

Remember the back seat can be lifted out to get a LITTLE better access to the cylinders if that helps.

Keep me posted.

afvman

[BRodri]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

also what kind of valves do these vehicles have are they manual or electric? if they are manual i have redone the fitting on the before and it really isn't that hard no different from doping a pipe for ng at the house just use the yellow teflon tape and wrap the threaded end and then tighten it up and then test it. if it still leaks you just might as well do it again because if it leaks once it will blow through and leak again no matter how tight it gets. and this is pretty high psi here so if you don't think you have it tight enough before you open the valve double or triple check that bad boy.

[afvman]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Yepper et al,

Be careful! When you mention valves and pipe dope or tape in the same sentence. Most high pressure fittings and valves use compression ferrules that should NOT require anything additional. They aren't designed for sealants.

Cylinder valves can be either NPT or straight SAE threads. One uses sealant, one uses 'O' ring seals.

Have you found the leak? Send pictures.


B/R,

afvman

[yepper]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Thanks Guru - no, haven't started to look for the leak yet - just got the car off the carrier Sat and started the DMV paperwork for licensure. The dealer emailed back with a suggestion of using soapy water, finding the fitting with the leak, then tightening with an open end wrench - I will let you know and proceed with caution - PS, how do you send pics on this forum? I have them, but do not know how to post.....thanks again

[jblue]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

PS, how do you send pics on this forum? I have them, but do not know how to post.....thanks again

Click "Post Reply" and then scroll down to the button that says "Manage Attachments".

[yepper]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Thanks for helping me post a PIC - not the best, but it is cold outside. Will try your suggestions to find the CNG leak soon - thanks

[yepper]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Well - to follow-up, I found total 3 leaks using soapy water after removing the lower cover which was easy and the upper cover where the extra tanks were tied into. Tightened fittings less than 1/4" and leaks stopped. Please note the lower cover was easy to remove, but the uppper cover of the existing tank was very difficult to remove - the screws were almost out of reach...but after 2 hours, got it off. I will let it sit overnight and respray this week with soapy water and keep sniffing for CNG smell. Question - what is the purpose of the covers? Is it to contain CNG leaks and vent to the outside? What if I cannot get a tight seal when I put them back on? Thanks!

[afvman]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Yep,

WAY TO GO.

Looks like you were lucky to get leaks fixed. The covers you asked about are just for any SMALL leaks that might get past the cylinder valves, NOT for any serious release of gas from the Pressure Relief Devices (PRD's). They should have a separate high pressure vent lines to the outside.

Stay warm,

afvman

[CNGCARS]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Yepper,

Do you realize your in california and afvman is in ohio? And you told him it was cold out here in California too funny...

[larrycng]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Yepper

First go to the "file library" and you will find a '96 Crown Vic Training Manual from Ford, it will give you a better idea of the system and it operation.

The Vent boxes that cover the top of the tanks are to keep vapors from getting into the passenger compartment or closed spaces within the vehicle. Those vent boxes are suppose to have a hose that carries the any vapors to the outside along with providing a path for the high pressure lines, wiring and PRD vent line.

When the boxes are assembled properly and the vent tube plugged, the boxes should hold around 20 water columb inches of water pressure (about 1/2 PSI pressure) Your pictures look like someone has taken the whole "upper tank assembly" and installed in the "well" of the trunk. If all connections are correct the system installed properly it should work great.

I've taken one of the vent boxes apart, in place, in the upper package shelf location -- it is a pain.

What are the expiration dates on the tanks? I'm trying to determine what year the vehicle the tanks and box came frome

later

Larrycng

[yepper]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Hi there Larry -

The tanks are from a 2002 CV - exp 2015 - rated 3600PSI. Thanks all for the info regarding the vent box cover. Looks like the leaks stopped - I will reassemble the vent covers and struggle with the screws. I agree the install is not in the best physical location because loss of trunk space - but works well so far. Yes, very ironic when I think 50 F is cold in CA when others (afvman) are facing bitter cold back east.

Be strong, safe, think positive and stay healthy - Happy Holidays all!!!

[Deeta]

Re: 2 questions CNG Smell + fill valve is "ball bearing" necessary?

Yepper, who did the installation? I am trying to get extended tanks installed in So CA but they are having trouble locating tanks so I will try out of state. If you don’t mind, what did it cost?
I just have to get my 03 running better (it's misfiring) so I am replacing the filter then tackling the plugs next. I just can’t find a manual shut off valve. It appears that these just use electric solenoids! Verifying before I take it apart.