StacksVerified U.S. regulatory reference

33 CFR §183.556

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
  1. (a)A fuel system must not have a fitting for draining fuel.
  2. (b)A plug used to service the fuel filter or strainer must have a tapered pipethread or be a screw type fitted with a locking device other than a split lock washer.