Stupid question on Fuel tank capacity.

[IwantMKIII]

Alright, well my fuel guage doesn't work properly, it only goes up 3/4 the way on a full tank. I experimented to see how many gallons i needed when it was on E to see if the tank was actually empty or if it was misreading. I put in about 14 gallons on E to make it a full tank. I tried looking for fuel tank capacities and came up with 70litres from a website. This is where i came into issues. I looked on a conversion website and it gave me 15.5 gallons...I figured that was wrong so i double checked on another and it gave me 18.5 gallons :icon_conf . After a bit more research i came to the conclusion the 15.5 gal is imperial vs 18.5 which is US std. So which is this 70litres referring to...is THAT itself imperial or US standard...i don't know, its late and im confused...:1zhelp:

 

[Yellow 13]

I think its an 18 gallon but you can only put in 14.

 

[IJ.]

70L= 18.5 USGallons= 15.4 Imperial gallons

 

[p5150]

To fix that all you have to do is pull out the sender unit and clean it. Not to hard to disassemble and clean the rheostat.

 

[jetjock]

I think its an 18 gallon but you can only put in 14.

Makes sense to me

 

[jetjock]

Not saying this is the problem but there's actually a reason behind why many Toyotas of that era have fuel sender problems today. It has to do with a slight incompatability between the materials used in the senders and the additives used in fuel during the 80s and 90s. There's a way to clean them up without removing the sender. Run a strong dose of polyether amine in the fuel, say one bottle to a 1/4 tank. Do that twice. Redline SI-1 is about 50% PEA and often does the trick. It'll clean your injector and valve deposits up too. If that doesn't work you'll probably have to clean it manually.

Also keep in mind the Supra's fuel gage is of the retaining type in that it's rotor is balanced and the area around it filled with a heavy silicone oil. As such it's very sluggish. You have to be patient after a fill up.

 

[IwantMKIII]

Not saying this is the problem but there's actually a reason behind why many Toyotas of that era have fuel sender problems today. It has to do with a slight incompatability between the materials used in the senders and the additives used in fuel during the 80s and 90s. There's a way to clean them up without removing the sender. Run a strong dose of polyether amine in the fuel, say one bottle to a 1/4 tank. Do that twice. Redline SI-1 is about 50% PEA and often does the trick. It'll clean your injector and valve deposits up too. If that doesn't work you'll probably have to clean it manually.

Also keep in mind the Supra's fuel gage is of the retaining type in that it's rotor is balanced and the area around it filled with a heavy silicone oil. As such it's very sluggish. You have to be patient after a fill up.

Personally i love the fact that its slow...it doesn't allow it to constantly misread, ie whenever you accelerate the feul guage changes drastically like in my chevy blazer. If you accelerate or brake even a little bit it will read between 1/2 tank and E. As far as the SI-1 is concerned, autozone kind of thing i assume? or possibly even like a walmart?

 

[IwantMKIII]

I think its an 18 gallon but you can only put in 14.

So...essentially it was really on E. I know toyotas keep a reserve when on E like 2 MAYBE 3 gallons...but 4? Seems like a lot

 

[Nick M]

Yes it is 18.5 capacity, but there is a fuel pump, and an expansion area. I filled it to 18.1 just to see once. The light comes on with 3 gallons left, well, when it is working right.

 

[IwantMKIII]

Theres an E light? lol

 

[jetjock]

As far as the SI-1 is concerned, autozone kind of thing i assume? or possibly even like a walmart?

I think AZ carries it. Pepboys does for sure. It's not that hard to come by. Gumout Regane (the yellow stuff in the clear bottle) also contain PEA. Understand I'm not guaranteeing this will work but at least it'll clean up the injectors and valves. Make the engine idle smoother too. Expect an odd sort of sweet smelling exhaust when doing this, especially with Regane.

Iirc the problem had to do with Toyota's use of silver in the fuel sender and the effects on it of earlier deposit control additives. They resulted in tarnishing which caused poor contact/resistance changes.

 

[starscream5000]

At least Toyota was thinking in right direction with silver being the best conductor of electricity, too bad they forgot about the tarnishing traits of it .

 

[Big Wang Bandit]

I need to work with mine. Its off a bit hehe

 

[SupaMan]

my gas gauge wonders around at anything above 3/4 it goes up and down whenever it feels like it itll drop like half a inch below the E line then jump to all the way full and go 1/4, 1/2, 1/4, 3/4, but once it gets down to 3/4 in the tank its fine.

i dont give a shit tho as long as the E light works im good.

 

[starscream5000]

Realistically, you shouldn't be driving on such a low tank of gas up to the point where the gas light comes on. The fuel pump is cooled by the fuel, when it's that low, it's not completely submerged and you run the risk of burning it up prematurly.

 

[shaeff]

i did this to mine years ago, and it's worked great ever since. just be uber careful!

http://www.supras.com/06/techcenter/display.php?QID=47

-shaeff

 

[Nomad707]

lol...
i hate the damn gas guage, it goes all over the effin place.. it will go from half a tank, to empty, to quarter tank, back to empty, then back to half..... i can never tell where the hell my gas is.

ANNOYING.