Fuel Tank Size?

[Rodt]

Finally achieved 400 miles on a full tank. very worried that the fuel warning light had been on for some time when I finally drove onto the forecourt.

very surprised that I could only squeeze 73 litres in but pleased as that's the first time I've done better than 25mpg. I thought the fuel tank was 85 litres (1996 LS400)?

Does this mean that I could have done another 50 miles before filling up or am I missing something?

[lordturns]

When I picked my LS up from Annan, I brimmed the tank and the distance from there to my home is 239 miles - I did this in just under half a tank at a steady cruise. I imagine that well over 400 miles is possible from an LS with this figure in mind. LPG beckons though for long term sensible use.

[ambermarine]

The trouble is the tank showing half full does not collerate to half use of the capacity if you brim it as you have filled the tank neck and the capacity of the tank as described in the owners manual does not include that. .The consumption of the fuel in the tank accelerates after the halfway mark.The risk in trying to get 400 out of a tank is picking up the gunge in the tank bottom. Your 230 odd mile as probably used 3/5 ths of the capacity

[lordturns]

The trouble is the tank showing half full does not collerate to half use of the capacity if you brim it as you have filled the tank neck and the capacity of the tank as described in the owners manual does not include that. .The consumption of the fuel in the tank accelerates after the halfway mark.The risk in trying to get 400 out of a tank is picking up the gunge in the tank bottom. Your 230 odd mile as probably used 3/5 ths of the capacity

And I imagine after 16 years, the tank will be full of gunge which leads me to ask the question - are any of those tank or engine flushes any good?

[PEPE]

Yes, tank capacity on LS 400s is 85.1 litres. I have kept very accurate records over 5,500 miles and my average fuel consumption is 26.96 MPG.

I refuel as soon as practicable after the warning light comes on and I usually have to add between 65 to 70 to refill the tank to the brim. If we take 70 litres to refill the tank then the fuel remaining in the tank was 15.1 litres which at 4.546 litres/gallon equals 3.32 galons. At 27 MPG this means that you should be able to drive an additional 89.68 miles, so yes, you could have easily driven for 50 additional miles without refuelling.

What surprises me, though is that you state that this is the first time you have done better than 25 MPG. I assume you must be doing a lot of urban driving. Would I be correct?

[Malc]

I just refill mine when the amber warning light comes on, divide the mileage covered by the litres put in, mutliply by 85 and often realise that I could have motored another 80+ miles before I would have been really empty.

On a bad day it's 425 miles per tank full, but on a good day, and with easy gentle soft driving, or constant 80mph driving, the tank has returned 500+ mptank

Malc

[ambermarine]

There are no reasons for trying to clean out the tank and all the associated problems that may occur by adding hostile ingredients to your sensitive fuel system.As Pepe says as soon as that orange light appears add fuel ,thats what the light is there for.

[Rodt]

Yes, tank capacity on LS 400s is 85.1 litres. I have kept very accurate records over 5,500 miles and my average fuel consumption is 26.96 MPG.

I refuel as soon as practicable after the warning light comes on and I usually have to add between 65 to 70 to refill the tank to the brim. If we take 70 litres to refill the tank then the fuel remaining in the tank was 15.1 litres which at 4.546 litres/gallon equals 3.32 galons. At 27 MPG this means that you should be able to drive an additional 89.68 miles, so yes, you could have easily driven for 50 additional miles without refuelling.

What surprises me, though is that you state that this is the first time you have done better than 25 MPG. I assume you must be doing a lot of urban driving. Would I be correct?

Most of my driving is commuting. Originally just 4 miles each way to work so obviously never really got up to temperature. Now I do 23 miles each way, of which 15 is dual carriageway and M25, 7 urban and 1 country lane. My training - courtesy of HM Government - is to 'make progress' so I could probably do better if I were a little lighter on the gas. And that kickdown is just addictive....

[Rodt]

LPG has been mentioned but as my commuter mileage is shared between the LS400 and an Alfa Romeo GTV and weekend fun is courtesy of Daisy, my yellow Triumph Toledo, my total fuel cost does not warrant the expense.

[steve2006]

As some of you may know I am breaking a 1997 JDM Celsior and sold the fuel pump during this ongoing process.

I first pumped all the fuel from the tank by powering the pump and then opened the tank to remove the pump.

What was surprising was there was probably another 5 litres of fuel in the tank after the pump had removed all it could so it would appear this would eliminate the possiblity of the tank ever running completely dry and therefore the problem of sludge being sucked through.

The tank also had no signs of sludge in the bottom and was perfectly clean inside after all those years.

[lordturns]

As some of you may know I am breaking a 1997 JDM Celsior and sold the fuel pump during this ongoing process.

I first pumped all the fuel from the tank by powering the pump and then opened the tank to remove the pump.

What was surprising was there was probably another 5 litres of fuel in the tank after the pump had removed all it could so it would appear this would eliminate the possiblity of the tank ever running completely dry and therefore the problem of sludge being sucked through.

The tank also had no signs of sludge in the bottom and was perfectly clean inside after all those years.

That is quite remarkable Steve, and completely opposite to what I thought.