Engine Cowling Removal; Engine Cowling Cleaning, Inspection And Repair; Engine Cowling Installation - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFTAIN SERVICE MANUAL
i.
Anti-seize lubrication should be applied to all loose fit spline drives which are external to the
engine and have no other means of lubrication. For certain assembly procedures, molybdenum disulfide, in
either paste or powdered form, mixed with engine oil or grease, may be used
j.
Temporary marking methods are those markings which will ensure identification during ordinary
handling, storage and final assembly of parts.
8-4.
TROUBLESHOOTING. Troubles peculiar to the power plant are listed in Table VIII-III in the back
of this section, along with their probable causes and suggested remedies. The table is divided into two parts,
engine and turbocharger. When troubleshooting engines, ground the magneto primary circuit before perform-
ing any checks on the ignition system.
8-5.
ENGINE COWLING
8-6.
REMOVAL OF ENGINE COWLING. (Refer to Figure 8-1.) The procedure for removing the cowling
is the same for either engine.
a. Release the fasteners (6 and 8) that attach the two cowl halves ( I and 2).
b. To remove the cowl half (2), disconnect the cowl flap control rods (11) from the flap (3), support
the cowl and release the screw fasteners (9) that secure the aft section to the nacelle.
CAUTION
Ground running with the cowling removed, maximum power
ground running is limited to two (2) minutes or cylinder head
temperature of 450
°
F, whichever is reached first. Prolong
ground running with the cowling removed could cause local hot
spots in the cylinders and irreversible engine damage.
8-7.
CLEANING, INSPECTION AND REPAIR.
a. The cowling should be cleaned with a suitable solvent and then wiped with a clean cloth.
b. Inspect the cowling for dents, cracks, loose rivets, damaged or missing fasteners and damaged fiber-
glass areas.
c. Repair all defects to prevent further damage. Fiberglass repair procedures may be accomplished
according to: Fiberglass Repairs, Section IV.
8-8.
INSTALLATION OF ENGINE COWLING. (Refer to Figure 8-1.) The procedure for installing the
cowl is the same for either engine.
a. Position the upper cowl half (1) and secure with screw fasteners (7) along the aft section of the
cowl.
WARNING
The cowling fastener locked position stripe must be maintained.
Refurbish or replace stripe if faded, missing or cowling is
repainted.
b. Raise the lower half (2) to join the upper half, secure the screw fasteners (9) along the aft section
of the cowl and lock the fasteners (6 and 8) that join the two halves. Fasteners (6 and 8) have a dark line painted
along the top half of the fastener and cowling. This is done so a visual check can distinguish when the fasteners
are open or closed. In addition to the paint stripe, each fastener (6) has a pin in the center of the screw slot that
will protrude into the slot, if properly locked, when screw driver is removed.
Revised: 3/31/94
POWER PLANT
2H7