Unusable fuel in a 337G

[Ernie Martin]

Does anyone know how much unusable fuel in each long-range tank of a 337G? It's non-turbo, non-pressurized.

Going through the manual I notice on the Instrument Markings section that my 337G has 21.0 lbs -- 7 gal -- of unusable fuel on EACH long range tank. So, out of 125 gal, 14 are unusable? Sounds like a typo to me that should have read 2.1 lbs or 2.1 gal (it's only 2.5 lbs per tank for each standard tank). I mean, LR tanks take you from 93 gal to 125 gal, or 32 more gal, so it seems ridiculous that 14 of those 32 are unusable. Maybe Cessna issued an errata sheet and it's in your manual, or do you have any first-hand experience?

Thanks for the help.

Ernie