my first fill

[flmgrip]

of course in pouring rain... no canopy... and watching the training video... hehe i guess that's the pain for saving a buck a gallon...

so what's a good fill and a bad fill ?

filled in garden grove. fuel gauge showed 3 points from full... filled yesterday in burbank... showed full all the way but first point went away after first mile...

what kind of fill should i expect to get all the way ? or is 3 clicks away from full a good fill ?

thanks

[freedml]

Re: my first fill

It might have been too cold to get a full 'fill'. The dispensers automatically reduce the pressure when it's cool outside to allow for expansion if it's hot later. Or it just didn't have the pressure, or you might have been at a 3000psi dispenser. A 'good fill' should get you to the top line or even above it.

[John Mitton]

Re: my first fill

I think flmgrip has a newer Civic GX with the highly-accurate electronic "bars" display. I think the answer is this: A fast-fill will never give you as much fuel as a slow fill due to the physics of rushing compressed gas into the tank and the resulting heat (a non-issue with a slow fill). The fast-fill dispenser stops when it senses 3600psi on the vehicle side of the pump. So once you start driving the tank cools down and the resulting pressure drops.

I usually get all bars at home with my slow-fill Fuelmaker FM-Q2-36 and the first bar stays lit for around 5 miles. I say usually, because as freedml points out the outside temp has a bearing on what pressure the Fuelmaker will fill to:

59F and above = 3600
50F = 3370
32F = 3050
14F = 2730
-4F = 2390
-22F = 2073
-40F = 1754

If you want to see all bars, try filling then driving around or just chilling out for 20 min or so before topping-off. I have even found this to work with my slow-fill... I can pump in another 1/2 GGE or so in the morning after an overnight fill.

[Highmarker]

Re: my first fill

John,

Here is what the NGV2-2000 specification says about temperature and filling. Section 4.2.2: Maximum Pressures.
Containers (CNG tanks) may be filled to a pressure not exceeding any of the following conditions:
a) A pressure that would settle to 1.0 times the nominal service pressure at a settled temperature of 70°F
b) A settled pressure of 1.25 times nominal service pressure at 135°F, or
c) 1.25 times the nominal service pressure immediately after filling, regardless of temperature
NOTE: The fill pressure shall be temperature compensated to prevent pressures from exceeding the maximum pressures that are defined.

I still find that interesting that Fuelmaker adjusts the pressure due to temperature. I mean if it takes 10 hours to fill a 10 GGE tank, I would think that the air temperature would change significantly if the vehicle was outside. So when does the Fuelmaker decide to shut off?

[flmgrip]

Re: my first fill

yes i do have the bars and they come in handy... it's about 10 to 12 miles per bar... nice to have a good visual on when you have to find a station

[scott]

Re: my first fill

Both of our (2006 & 2008) cars do the same thing. I topped off the 2006 at Burbank last Thursday ($1.92.5) and got all bars lit. After a few blocks the top bar went out. I frequently fill at home when the tank is really low and top it off at the Santa Monica station (today $2.64.9). At Santa Monica, about half the time, I get the last bar to show, but it goes out in one or two blocks as well. I do not think that the last bar means much. I am sure it is pretty darn close to 8gge when the pump is finished. I also noticed when I last filled at Van Nuys and the 3600psi side was in-op, I used the 3000 side and all but the last bar lit.

[cngmike]

Re: my first fill

The difference between a 3000 and 3600 is about 11% more fuel.

[Green GX]

Re: my first fill

of course in pouring rain... no canopy... and watching the training video... hehe i guess that's the pain for saving a buck a gallon...

so what's a good fill and a bad fill ?

filled in garden grove. fuel gauge showed 3 points from full... filled yesterday in burbank... showed full all the way but first point went away after first mile...

what kind of fill should i expect to get all the way ? or is 3 clicks away from full a good fill ?

thanks

flmgrip,

I usually fill my '07 GX at one of the 3600 psi pumps at the Clean Energy station in Santa Clarita. It'll light up all the segments, but the first one will usually go out after driving the first mile and a half. I've only had the car since October of '07 so, the weather is relatively cool and the gas probably cools a bit dropping the pressure and turning off the far left segment on the gauge.

I don't know what you're driving, but the '07 GX has two full marks on the gauge; one for 3600 psi and one lower on the gauge for 3000 psi.

Bill

[flmgrip]

Re: my first fill

yeah... i have the 08... same here at clean energy i got the last bar for 5 miles... but it seems that if i get at least to the 3000 mark i am doing ok... soon my phil will do most of the work anyway....