Fuel tank

[xclogan]

According to Volvo the fuel tank (on a 1998 V70XC, built in 12/97) holds 70 liters (18.4 gallons) maximum.  There is a small amount fuel that can not be used (as per the Owners Manual).  Now.... is the 1.8 gallon reserve included in the 18.4 total or is it 1.8 gallons more fuel (this is what I thought)?

The reason I ask is that I filled the tank yesterday for the first time since the dealer filled it when I got it.  It took 18.799 gallons.  18.799?  Either the pump was not right or I don't know what the actual max fuel capacity is.  I believe the total capacity may be 20.2 gallons (18.4+1.8), or is it 18.4 including 1.8 reserve + some more fuel somewhere.

I also know that you can't use all of the fuel you put in when filling up, so that the total "USEABLE" fuel capacity is what I am looking for here.  ANY IDEAS?!?!?!?!?!

This is for my spreadsheet that tracks fuel use/cost and mileage.

Any help is sincerely appreciated!!!!!

[TheEngineeringDon]

I have a (UK) XC pricing and specs. brochure and this gives a useable fuel capacity of 66l (approx 14.5 gal).

[xclogan]

14.5 gallons, is that the British measurement or US, or are they the same.....

About 4 gallons from the full fuel tank down to the usable amount of fuel seems like a lot of fuel to be sitting in the system.

Thanks for responding......Anyone got any other ideas?

[TheEngineeringDon]

Thats the British measurement, an English gallon is 4.55 litres (U.S. is 3.79 litres). Having said this I got 68 litres of fuel in the other day, and I still had 10 miles to 0 on the computer...

[xclogan]

I am just going to use 19 gallons as the maximum amount possible.  This includes the 1.8 in reserve (low fuel light). And as Volvo put's it a "substantial amoun of room left for expansion" (1998 Owners Manual, page 67, "Refuelling" section).

It initially seems to be close to, if not correct, as I got my XC down to 5 miles to zero the other day when I pumped the 18.799 gallons and that works out to .20 gallons left in the tank.....which sounds like enough to go 5 miles.....

I am not usually in the habit of getting that low on fuel but wanted to get as close as possible to an empty tank and filling it to get the total capacity and the useable capacity figures...

Thanks all!

[gbooth]

On my recent trip to eastern Canada I had an opportunity to put 70.36 liters and 73.38 liters into the "70 liter" tank on my V70-XC 2002.

gb

[wiz]

Don't gas the tank until it is overflowing. There is a vapor venting system at the top of the tank that uses a charcoal canister - if you persist in flooding it with gasoline it won't work. Leave the fill at the auto shut-off and you will be OK. Also there is about a 1.5 gallon "leftover" area in the tank for the fuel to expand in hot weather.

[Jcurrie]

According to Volvo Canada, you have to stop filling the tank as soon as the gas station pump clicks off when you near a full tank ~ 66 litres (whether or not you've filled the tank to it's absolute maximum). If you don't you'll ruin the Mass Air Flow Sensor and the Check Engine light will stay on indefinately until the sensor is replaced. I know from experience!!

Hope this helps!?!?!?!

[xclogan]

After a month of testing I am going to settle on 19.2 gallons max fuel capacity.  Which sounds about right...

17.4 gallons capacity (as per '99 owners manual)
1.8 gallons reserve
19.2 total fuel capacity

And yes... I never "overfill" the tank.  I might go to the "second click" sometimes, but that is as far as I go.  I did put in 19.1 gallons the other day...and yes it really was as close to being out of fuel as I want to be.  
FYI- No I do not drive around trying to run out of gas!  I usually get fuel just about or before the light comes on.

Thanks for all the assists and information!

[subaruguy]

now when we say "reserve" it has a secondary tank like an old puck-up truck? otherwise i dont think i would refer to it as a reserve, its just low on fuel when the light comes on.