Press Release, January 30, 2018: ABLE SALES was designed, manufactured, and installed aftermarket and original equipment gasoline and diesel transfer tanks. Because of DOT ambiguity, the sheer legality of gravity fed systems remains unclear. But, ABLE SALES believes safety and legality issues can occur with gravity feed supplemental gas systems which will violate elements of US DOT regulation 49 CFR 393.67, a requirement of ALL fuel techniques.


From a car performance standpoint, gravity feed fuel systems can adversely affect federally mandated, manufacturer executed, on-board vehicle diagnostic systems. While in the case of many brand new vehicles, a gravity fed system keeps the gas tank overfull and can likely result in a diagnostic problem code. In addition to being a nuisance, drivers may miss valid vehicle issues because the check engine light remains on.


In all fuel transfer tanks, there is a rollover valve which is normally open to atmosphere. The rollover valve utilizes a mix of float weight, spring force, and buoyancy to work properly. When the float is immersed in fuel, the float (valve) shuts, effectively preventing gas leakage at the unlikely event of a rollover. The over-fill trends of conveyor systems direct a few users to seal the rollover OEM valve(s). In the lack of a rollover valve, then the septic tank will likely continue to flow fuel into the vapor space of the main fuel tank.


A properly functioning rollover valve will close if the fuel level reaches on the float of the valve. Safety concerns reach beyond simply spilling gas during regular operation of air fed fuel methods. To maintain performance, the DPF unit needed to go through a regeneration cycle at which in some vehicles fuel is pumped into the catalyst bed of the DPF and burnt. Throughout regeneration, many DPF units hit temperatures of 600°C (1,112°F). Diesel fuel has an autoignition temperature of around 260°C. Fuel leaking from the rollover valve onto the gravity fed system would be in close proximity to the DPF and the prospect of fire is significant. If the gravity fed system overfills the main tank by introducing fuel into the vapor area, then there is a potential for fire.


Another factor is portable diesel fuel tanks pressure. Insufficient vapor space in gravity fed systems might create pressure build up in the primary fuel tank, causing fuel to leak past the anti-siphon/anti-expulsion valve hence, when removing the gas limit, the operator may be sprayed with fuel. Item development confirmed by FMVSS 301 has been instrumental in ABLE SALES designing the safest after market fuel tanks and fuel systems available. We are proud of our investment in crash tests, and therefore are confident in the safety and legality of our systems.


ABLE SALES's engineering team has evaluated OnRoad gravity-fed supplemental gas systems and it has ascertained that due to safety, environmental, and legal concerns, which can be inherent in the structure and performance of gravity-fed auxiliary fuel systems, ABLE SALES won't endorse or promote the design, setup, or use of road gravity-fed auxiliary fuel techniques. Customer safety and fuel-system legality are still function as our priorities after more than 175,000 gas systems marketed and a lot more than 30 years in industry.



CONTACT US:

Able Sales (VIC)

LOCAL CALL 1300 735 902

Unit 1 / 79 Maffra Street, Coolaroo, Victoria 3048

Monday-Friday: 8am-5pm | Saturday: CLOSED

PH: (03) 9302 3602 E: [email protected]