Piper Arrow IV Turbo Maintenance Manual page 600

4. Check and Adjustment of Idle Fuel Pressure:
The following setup procedure is accomplished with the boost
pump OFF and the engine thoroughly warmed up.
A. Back off the idle speed adjusting screw two turns. (Refer to Figure 73-4.)
B. Start engine and warm up at 1,500 to 1,800 RPM until the oil pressure is in the green arc, cylinder
head temperature is in the lower one-quarter of the green arc, and the oil temperature is 160° to 180° F.
C. While maintaining 700 + 25 RPM, set the idle fuel pressure at 6.5 + 0.25 psi by adjusting the idle
pump adjustment screw (refer to Figure 73-5, item 6); clockwise adjustment increases pressure;
counterclockwise adjustment decreases pressure.
5. Check and Adjustment of Idle Mixture: (Refer to Figure 73-4.)
A. Operate the engine at 1,500 to 1,800 RPM until cylinder head temperature is in the lower one
quarter of the green arc, and the oil temperature is 160° to 180°F.
B. Reduce the engine speed and stabilize it at 700 + 25 RPM.
C. Slowly, but positively, move the mixture control from the full rich position to the idle cut-off. The
engine speed should increase 75 to 100 RPM before beginning to drop toward zero (upper cowling
removed).
D. If the engine speed increase is less than 75 RPM, adjust the idle mixture adjustment to enrich the
mixture (counterclockwise). If the engine speed increase is more than 100 RPM, adjust the idle
mixture to lean the mixture (clockwise). Recheck the adjustment as outlined in Step C, to insure
the idle mixture is adjusted within limits specified.
6. Check and Adjustment of Idle Speed: (Refer to Figure 73-4.)
A. With the idle fuel pressure and idle mixture set in accordance with instructions given in Steps "4"
and "5", cylinder head temperature in the lower one-quarter of the green arc, and oil temperature
at 160° to 180°F, set engine speed at 700 + 25 RPM.
B. Adjust the idle speed adjusting screw until contact is made with the throttle arm stop.
After final adjustment, recheck the idle fuel pressure, mixture
and speed to ascertain that all are within specifications given in
previous steps.
7. Check and Adjustment for Full Power Performance: (Refer to Figure 73-5.)
Before attempting full power checks, be sure that the brakes are
properly maintained and set, and that the ground conditions will
not permit the wheels to slip during full power check.
Effectivity
PA-28RT-201T
PIPER AIRCRAFT
PA-28RT-201 / 201T
MAINTENANCE MANUAL
—NOTE—
—NOTE—
—CAUTION—
—NOTE—
Fuel flows are given for sea level density altitude.
3C20
73-20-02
Page 73-07
December 1, 1978