Piper Arrow IV Turbo Maintenance Manual page 310

AUXILIARY FUEL PUMP SYSTEM ADJUSTMENT. (INSTALLED)
1. Install a calibrated pressure gauge in the fuel line between the electric fuel pump and engine.
2. Remove the aft access panel in the baggage compartment. The slider resistor is located at station 165.5
attached to the plate containing the voltage and over voltage relays.
3. Disconnect the wire from the auxiliary pump circuit breaker.
4. From an external power source containing a voltmeter, connect the negative lead to ground and the
positive lead to the slide resistor high terminal.
5. Connect a calibrated voltmeter across the auxiliary fuel pump, and adjust the external power source
until 12.0 to 12.5 volts direct current is indicated. Record the voltage reading from the external power source.
6. Check the calibrated pressure gauge. At least 31 to 37 psi should be indicated.
7. Connect the positive lead to the "LOW" power terminal of the slide resistor.
8. Adjust the power supply voltage level to obtain that recorded in step 5.
9. Slide the "LOW" terminal on the resistor to obtain a pump pressure of 8 to 10 psi.
10 Readjust power supply and "LOW" terminal to insure a pump pressure of 8 to 10 psi at a power supply
voltage of that previously recorded in step 5.
11 Secure the "LOW" terminal slider.
12 Connect the positive lead to the "MEDIUM" power terminal of the slide resistor and adjust the power
supply voltage level to that recorded in step 5.
13 Position the "MEDIUM" terminal on the resistor to obtain a pump pressure of 23.5 to 24.5 psi, and
readjust the power supply and terminal to insure that pressure at a power supply voltage recorded in step 5.
PIPER AIRCRAFT
PA-28RT-201 / 201T
MAINTENANCE MANUAL
Figure 28-6. Aux Fuel Pump Variable Resistor
2B7
28-20-11
Page 28-12
Added: August 17, 1982