1987 XJ6 fuel tanks

I should perhaps know this but rarely drive this auto and just trying to get it running again. The question is what is the capacity of each gas tank/ I got 5 gallons and put it into one empty tank and the gauge reads about 3/4 full. That doesn’t seem right to me as I though each tank should hold about 10 gallons each. Something must be wrong with my sending unit as it did read zero without fuel.
Lee

Each tank, 12.6gal.

Dave

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Due to the shape of the tanks and the basically linear resistance response of the tank units, Lee - the gauge is not very precise at intermediate readings…

However, your tank(s) may have suffered implosion due to some event of high tank vacuum. The reduces tank capacity, most noticeably in the mid range…

Apart from visual inspection; the only way to check this is to see how much fuel is required to fill the tank(s). The tank units/gauge measures fuel levels - not volume…

Frank
xj6 85 Sov Europe (UK/NZ)
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