Refueling options from Radium Engineering
Radium Engineering has been hard at work developing products to make fuel cell filling easier and faster. These new parts work seamlessly with the Radium Fuel Cell Surge Tank (FCST) and associated fuel cells, which have proven to be a popular fuel delivery solution for performance vehicles.

In the past, it was left up to the installer to design and fabricate a custom remote filling solution for the Radium FCST, often requiring additional parts from other companies and making something work. This new product line means the installers can purchase all parts from Radium Engineering and know everything is going work perfectly together.

Because vehicles have different priorities when it comes to refueling, Radium has released several solutions to suit most needs. With so many new products to choose from, Radium has developed this simple explanation to help select the correct products for the customer. By answering a few questions, the customer can be assured they are getting the parts they need.

Understanding Terminology
Filling of the fuel cell can be done one of two ways; "direct fill" or "remote fill". The terms "direct" and "remote" are used often when describing Radium Engineering fuel fill products. Direct fill uses a screw-off cap to pour fuel directly into the cell, while remote filling refers to a body-mounted fill point connected to the fuel cell fill neck with a large diameter hose.
                                                                                        Direct Fill Example
Example of Direct Fill                                                                                         Remote Fill Example
Example of Remote Fill"Standard fill" or "dry break" refer to how the fuel is delivered to the fuel tank from the dump can (or fuel jug). Dry-breaks are handy when refueling needs to be completed quickly in a competitive environment. No caps need to be unscrewed, and fuel is forced into the tank with gravitational pressure. In the past, standard fill options were convenient due to compatibility with common fuel jugs and gas station nozzles. However, the Radium dry-break filler's female dry-break receptacle can be unscrewed. This allows filling with a standard gas station nozzle or non dry-break spout. This is a unique feature to Radium dry-breaks.

Radium Engineering standard remote mount filler using a fuel jug (shown below).

Radium Engineering standard remote mount filler (p/n 20-0505-V) can be used with a standard gas station pump nozzle (shown below).


Radium's dry-break fuel fill connectors, shown below, are an excellent choice when refueling needs to be completed quickly. These require special dump cans and fuel cell vents which can evacuate air quickly during the filling process.


Fuel Fill Product Lineup

Radium has assembled 4 "Complete Fuel Cell Refueling Kits" as detailed below. These comprehensive kits include all parts needed to make a complete filling and venting system that works as designed. The quick fill systems will fill at a rate of approximately 20 gallons per minute using the supplied high-flow venting accessories.

The product page for these complete fuel cell filling kits can be FOUND HERE.
The complete kits include everything needed, including a dump can and vent line, to handle the refueling and venting of a fuel cell equipped with a Radium FCST. 

Other Options
If a complete kit is not an ideal solution, then a custom filling system can be constructed using the products shown below.

A fuel neck bolts directly to the top of the Radium FCST via the 6-bolt hole pattern. Several different fill necks are available for direct and remote fill applications.
All direct mount fill necks can be FOUND HERE.
All remote fill necks can be FOUND HERE.


For remote fill applications, Radium offers the two remote (body) mounted fill points shown below, one for quick-fill dry breaks and one for standard filling. Each are designed to be used with a 1.5" ID fill hose. These products can be FOUND HERE.
The two options below share the same outer "shell", meaning that the dry-break recepticle in 20-0504-V can be unscrewed and replaced with the flush-mount cap from 20-0505-V, or vise-versa. This modular design is unique to Radium products and provides flexibility in what fill method can be used.

These remote fill points feature a very small pressure equalization hole for venting the fuel cell when the main vent may be closed, such as after quick filling. These small holes have a ball that will plug them in the event of a roll-over.

Proper venting is an important part of fuel cell refueling. Fuel can only get in as fast as air can get out. Large high-flow vents are needed for quick filling. A Dynamic Safety Vent (DSV) valve not only offers venting of the fuel cell, it closes the vent in case of rollover, preventing fuel loss. The Radium internal high-flow DSV (P/N: 20-0535) features a floating ball that closes the vent when fuel level reaches a certain calculated point, stopping fuel flow into the cell. This prevents over-pressurizing of the cell during gravity-powered quick filling.
An external vent such as 20-0462 will not automatically shut off fuel flow at a calculated point and is more suited for systems needing a high-flow vent, but without the aut-shut-off control.

NOTE: Radium increased the vent port size on the FCST December 2018 to make it compatible with quick filling. For older 20-014X-XX FCST units that want to use quick filling, an additional vent needs to be added. See part number 20-0439 below. The vent kits are a convenient solution for plumbing a vent line from the fuel cell vent port to outside the vehicle.
Dynamic Safety Vent valves can be FOUND HERE.
Vent Kits can be FOUND HERE.


The accessories below can be useful when putting together a custom system, or when replacement parts are needed. They can be found on various product pagesHERE.

Please contact info@radiumauto.com for assistance with selecting products.



Details