yeah again... fuel tank question...

[B318M42W]

i'm having trouble identifying my fuel tank's capacity...

so here's what I know about it: it's been changed once before in 2004 i think?(used.. PO...)
my fuel gage has 55L written and a dot a bit after it (and when I fill up It gets to that dot)

no transfer pump, as there is a hard line that connects both 1/2 of the tank.
both 1/2 seems about the same size, but the left cheek is about 1" shorter

and here are 2 pics from the top of it...

I'd like to point out that there's no visible opening at the top for the left side...







thanks for any input!!!

[1991 E30 M42]

carry a small fuel can with you that you know how muck fuel is in it and drive your car till it cuts off

[B318M42W]

thanks for the idea, but it's more for a replacement issue... that tank is pretty much done (or needs serious expensive repairs).

[1991 E30 M42]

oic, they only list one tank, METAL FUEL TANK   55L   09/1983   16111177983   $427.43