3
PRESSURE SENSOR/GAUGE
The DMR is NOT equipped with a port for pressure reading. Do not connect a sensor or gauge to ports B or C. If a pressure sensor or
gauge is needed to monitor system pressure, it must be installed elsewhere in the system such as on the fuel rail or the feed line
leading to the fuel rail. Radium offers a variety of adapter fittings to accomplish this.
START UP
NOTE: The DMR is not pre-set to any particular pressure setting out of the box.
Reconnect the battery.
Turn the ignition to the ON position to allow the fuel pump to prime the system (do not start the engine).
Cycle the ignition power a few times and check for fuel leaks.
If there are any leaks, they must be corrected before proceeding.
Start the engine and recheck for leaks.
Use a pressure gauge or sensor to adjust the fuel pressure according the procedure below.
FUEL PRESSURE ADJUSTMENT
The DMR can be fine-tuned for the specific application using a fuel pressure sensor or gauge (mounted elsewhere in system).
Determine what the target static fuel pressure setting should be before beginning this procedure. This target setting can be different
for many vehicles. Consult with the EFI tuner, or match factory pressure setting specified by the manufacturer.
To set static fuel pressure, disconnect the vacuum line from the DMR and temporarily plug the vacuum line to prevent a
leak. During this test, leave the DMR barb open to atmosphere to allow venting.
Activate the fuel pump by starting the engine or manually powering the pump.
Loosen the jam nut on the top of the DMR using a 3/8" wrench.
Using a 3/32" Allen wrench
a)
Tighten the set screw (clockwise rotation) to increase fuel pressure.
b)
Loosen the set screw (counter-clockwise rotation) to decrease fuel pressure.
Once the fuel pressure is set at the target, tighten the jam nut.
Turn OFF the engine and secure the vacuum hose on the DMR.
SERVICING
Relieve fuel pressure.
Use a 5/64" Allen wrench to gradually remove the 5 screws using an alternating cross-pattern sequence.
Inspect the diaphragm for excessive wear and possible leaking.
For replacement parts, please contact Radium Engineering.
To change the orifice, use a 7/16" socket wrench.
Reference diagram for reassembly. The diaphragm and seating surfaces MUST be clean for proper sealing.
BE CAREFUL TO NOT INSTALL THE SPRING HAT UPSIDE DOWN
Clock the billet cap to point the vacuum barb as needed.
Tighten the 5 screws gradually in an alternating cross-pattern sequence.
