checklist - ERAU ETA - Embry-Riddle Aeronautical University

PA-28R-201 SOP 63
8. MAGNETOS (175/50) CHECK
CHECK the MAGNETOS by rotating the key in the ignition switch to the R
(Right) magneto position and noting engine RPM. Rotate the key to return
to the Both position (to ensure clearing the spark plugs on the other
magneto). Then, rotate the key to the L (Left) magneto position and note
the engine RPM. Rotate the key to return to the BOTH position. RPM drop
for either magneto should not exceed 175 RPM, nor should the difference
in RPM between the two magnetos exceed 50 RPM.
NOTE
After checking one magneto, do not check the other magneto
until the engine returns to 2000 RPM. Keep engine operation on
one magneto to a minimum. Ensure that the key is in the Both
position after the magneto check.
If a fouled spark plug is suspected: 1) Smoothly advance the
throttle to set 2300 RPM, 2) Lean the mixture to obtain a 100
RPM decrease for 45-60 seconds; 3) Enrichen the mixture to
FULL RICH, 4) Smoothly reduce the throttle to set 2000 RPM;
then, 5) Proceed with the magneto check.
NOTE
Vapor may form in the fuel system during ground operations
when ambient temperature exceeds 85°F. See page 16 for
procedures.
9. PROPELLER CYCLE
To check propeller operation, CYCLE the PROPELLER by moving the
Propeller Control fully aft and then forward to observe a decrease in RPM
(Tachometer).
CAUTION
N
Allow no more than a 500 RPM decrease to avoid subjecting the
cylinder heads to an unnecessarily high manifold pressure
which could cause internal engine damage.
Allow the engine speed to stabilize at 2000 RPM before each
subsequent check.
Rev 06 © Embry-Riddle Aeronautical University Revised 07-01-2012