new owner of a bi-fuel ford f-250

[wfg]

Hi All,

I just purchase a use 1999 Ford F-250 bi-fuel cng and gas truck. This truck use to belong to the gas company. It have a switch on the dash (Alt/Gas). The switch is set on Alt, but my gasoline gauge is decreasing. Therfore I must be running it on gas, but i would like to operate it on cng. I went to fill up the cng tank and the pump just shut off at $0.54. I tried the next pump and it also shut off but at $0.37. It this mean that my cng tank is full and how would I determine that the tank is full? Is there a shut off valve that is preventing me from filling this tank? I couldn't find this valve anywhere under the truck bed. The only valve that i saw was Balston and it don't have a shut off handle. Should I just loosen this valve up with the wrench? This truck is equipped with GFI control system. I'm appreciate if someone with these knowledge could help me out with my situation.

Thanks,
wfg

[cnghal]

Re: new owner of a bi-fuel ford f-250

Wfg,
Please don't "just loosen" anything with a wrench. We don't need any more California CNG Incident Statistics.

First, find a CNG shop or CNG System Inspector near where you live and get them to check out your truck and train you on all things CNG. That's assuming the gas company or Clean Energy don't provide fueling training.

Second, get down on your knees and pray you don't have a Compuvalve problem. Take some time to run a search of the forums for information on the GFI Compuvalve and become familiar with it.

Welcome to CNG Chat, and good luck with your new purchase.

[boomr]

Re: new owner of a bi-fuel ford f-250

Sounds like the tank is full. I have yet to meet someone with a 98 Ford F150 with a working compuvalve, but I don't get out alot.

[wanpakumono]

Re: new owner of a bi-fuel ford f-250

I also own a Bi-fuel F150 (not that there is anything wrong with that). When you are using CNG, the green light should be illuminated on the 'Alt/Gas' switch. If it is, then the gas gauge is telling you the amount of CNG you have. The gas gauge is used for both fuels.

[wfg]

Re: new owner of a bi-fuel ford f-250

Thanks,

The green light on the 'Alt/Gas' switch is not lite up on my truck. Does anyone know why?

[cnghal]

Re: new owner of a bi-fuel ford f-250

Wfg,
It's been a while since I've seen an operating manual for a bifuel, and I may be mistaken, but I think you're supposed have the switch in the Alt position when you start the truck.
I remember there are several discussion threads on the switch and diagnosing problems with the compuvalve in the forums, probably in the Ford forum. There are also some manuals in the File Library.

[wanpakumono]

Re: new owner of a bi-fuel ford f-250

Wfg,

You need to make sure that you set the switch to the setting you want before turning your ignition on. If you have the switch set to 'Alt' and, when you turn on the ignition, the green light is not on, then you definitely have a problem.....Most likely compuvalve-related. Just be aware that you cannot switch between fuels "on the fly" on this model.

Hope this helps.

[wfg]

Re: new owner of a bi-fuel ford f-250

Hello All,

Sound like i have a bi-fuel compuvalve issue. Does anyone have the run down on how much it will costs me and where could i have it service? I tried a few of local Ford dealers in southern california and they turned me alway. Is there any way to fix this because I cannot run my truck on CNG. PLEASE HELP

Thanks,

[wmarsden]

Re: new owner of a bi-fuel ford f-250

wfg,
I own and drive a '99 Ford bi-fuel. Luckily, I have a spare compuvalve and several spare high pressure regulators that I've picked up. It is very expensive for Ford/Teleflex/GFI to do any repairs on the compuvalve.

Couple things for you to check: there are two fuses mounted on the side of the battery box. These are used for the CNG system. Make sure they are good. Under normal operating conditions, if there is a problem with the compuvalve you will get a blinking green light on the Alt/Gas switch on your dash. If you don't get a green light at all, there may be a problem with power to the compuvalve.

Personally, I like my truck and have not had any major issues with it yet. But I know that the compuvalves and high pressure regulators routinely have issues. There is a shop here in Utah that may be able to help you out: CNG Technologies of Utah. Here is some contact info: Brandon Wicknick 801-637-4570 [email protected].

Good luck and let me know how it goes.

[wfg]

Re: new owner of a bi-fuel ford f-250

Thanks to all who responded with great info. I checked the two fuses mounted on the side of the battery box and changed both of them. I'm still not getting the green light on the Alt/Gas switch. ??? Question, when it switch over from cng to gasoline will the green light on the switch stay on or turn off? I will contact Brandon Wicknick with CNG Technologies for some advices.

Thanks,

[wmarsden]

Re: new owner of a bi-fuel ford f-250

If the Alt/Gas switch is in the Alt position when you start your engine it will glow green (assuming all is well and you have CNG pressure, etc). When the green light is on it means you are running on CNG. The gas gauge shows relative pressure in the CNG tank. When you run out of CNG, the system automatically switches to regular gasoline and the light goes out.

If you toggle the switch while running, it does nothing.

If you don't get a green light on, there is trouble. Usually though, the light will blink if the system detects an error.

Call Brandon. He is very good.

...and find yourself a replacement compuvalve