Fuelab 56502 High Flow Fuel Pressure Regulator - Manual (Page 3)

4. Apply light oil onto the threads of the Adjustment Screw. Thread the Adjustment Screw by hand until a slight
tension is felt, this position is the minimum pressure setting. Do not tighten screw any further. Pressure is to
be adjusted later in these instructions. Install the Flat Washer, then the Jam Nut. Tighten the Jam Nut hand
tight for later adjustment.
5. Install Bracket to regulator using supplied Bracket Screws and Bracket Lock Washers. Tighten Bracket Screws
between 25-40 in·oz of torque (snug, do not over tighten screws).
6. Install the fuel fittings (not supplied). The threads used on these Fuel Ports are not tapered or pipe threads.
Do not use Teflon

thread tape or thread sealant on these threads, as this can cause leakage or introduce
debris into the fuel system. Fittings to be used with these style of ports require use of the enclosed–906 O-
rings for proper sealing (reference diagrams, below). Use light oil to lubricate the O-rings just prior to
installation. Install the O-rings onto the fuel fitting first. Position the O-ring in the thread relief of the fitting as
shown in the diagram, below. Thread fitting into regulator and tighten between 5 and 15 ft·lbs of torque.
7. Use Teflon

tape or thread sealant on all 1/8”-NPT fittings to be used for the Gauge Port and Pressure
Reference Port (see diagrams, below). Install fittings or plug as required. If pressure reference port is not
plumbed, then install the Sintered Bronze Filter (supplied) and allow fitting to vent to atmosphere (do not plumb
or plug port). Use of Port Filter (only) does not require the use of Teflon

tape or thread sealant. For extra
level of safety, pressure reference port can be plumbed with float bowl vent, in case of rare diaphragm failure.
8. Install regulator assembly into vehicle, fastening the bracket to the vehicle. Attach fuel lines, Gauge Port line (if
external pressure gauge is used in application) and Pressure Reference Port line (if applicable). Boosted
applications (such as turbo or supercharger) will require a hose clamp on barbed fitting to prevent hose from
coming loose. Use of –3AN or –4AN fitting and line can also be used as a substitute to the barbed fitting.
9. Inspect fuel system for any contact of fuel lines or wires with other components that can cause chafing or
rubbing. Secure all components and fuel lines.
10. Connect the vehicle’s battery. Operate fuel pump, while monitoring fuel pressure. The pump will have to
operate several seconds (30+) to prime and drive air out of the fuel system. Generally, this system should be
capable of self-priming. Fuel system pressure should read about 4-5 PSIG (use an external gauge for
adjustment if a permanent gauge is not used). Inspect vehicle for any leaks. Turn off fuel system and repair
any leaks that may be present before continuing.
11. When adjusting pressure, be sure that fuel pump is operating to monitor pressure. Increase pressure by
rotating adjustment clockwise. Do not thread Adjustment Screw past jam nut within 1/8”. Over tightening the
adjustment screw can damage the regulator. For repeatable readings, engine should be operating normally at
idle.
12. After final adjustment of fuel pressure, to desired level, tighten Jam Nut. Road test vehicle, and retest pressure
upon return to ensure accurate adjustment.
-10AN Return Line Port
Fitting Shown
toward Regulator
Install with Cup
Example -10AN
-910 O-ring Shown,
Installation
Fitting Shown (Not Supplied)
(Not Supplied)
for gauge or fitting)
Front
1/8"-NPT Gauge Port
Gauge Port Plug
(Logo)
prior to Fitting
-910 O-ring
Example -10AN Port Style Union
(can be substituted
Port Style Union
Example -10AN
Port Style Union
Fitting Shown
(Not Supplied)
-10AN Inlet or Outlet
Port, Both Sides.
Pressure is
Regulated at
Both Ports.
Jam Nut
Number
Identification
flat Washer
Unique Serial
(Use Fitting or Filter)
Reference Port
(3X) Bracket Lock Washer
Adjustment Screw
(3X) Bracket Screw
1/8"-NPT Pressure
(1/8") Sintered Bronze Filter
(For Naturally Aspireted)
(1/8") Barbed Fitting (can be
substituted with other fitting,
for blow-through applications)
105020622-1, No Rev Sheet 3 of 4