Originally Posted by peghall
... Plastic fuel
tanks are made of high density CROSS LINKED PE, which is impervious to petroleum. They're also supposed to meet some other criteria for USCG certification
...a minimum wall thickness, all fittings on top, no surface that can allow liquids to pool etc. but that may only apply to tank mfrs, not to individual owner one-offs ...
Nonetheless good/best practice ought to apply to us, all.
ABYC Standard H-33, Diesel Fuel Systems, is silent on the issue of location of diesel fuel tank
openings and therefore does not prohibit openings below the top of the tank.
XPE (cross-linked polyethylene) tanks undergo what's known as hydrocarbon expansion, which causes them to grow between 3 and 5 percent upon their first exposure to fuel. While this is a onetime event, it must be taken into account (a 45-inch-long tank could grow to 47 inches). Cribs, cleats
, straps, and other tank supports must be adjustable to accommodate this expansion.