Piper Navajo PA-31 Service Manual page 486

PIPER NAVAJO SERVICE MANUAL
NOTE
All adjustments to the wastegate valve must start from the closed
position first and then to the open position.
8-33m. INSTALLATION OF EXHAUST WASTEGATE ASSEMBLY.
a. Install wastegate assembly with gasket between exhaust transition and tailpipe.
b. Secure wastegate with V band clamps and torque clamps to specifications given in TableVIII-IA.
c. Connect oil lines and drain line to wastegate assembly.
NOTE
It is recommended that the wastegate valve be lubricated with a
decarbonizing agent (Mouse Milk, WD-40 or equiv.) at the butterfly
pivot points every 50 hours. Purchase Mouse Milk from: Worldwide
Aircraft Filter Corp., 1685 Abram Ct., San Leandro, CA 94577.
8-33n. TURBOCHARGER
DECOKING.
Mouse Milk. penetrating oil or equivalent may be used for decoking the turbine and compressor drive
shaft by the following procedure:
a. Disconnect the oil inlet and outlet lines from the turbocharger and allow all oil to drain.
b.
Cap the oil outlet port on the turbocharger.
c. Pour the Mouse Milk into the oil inlet port of the turbocharger and allow the unit to soak overnight.
d. Drain all Mouse Milk from the turbocharger and flush the unit with engine oil.
e.
Prime the turbocharger in accordance with Paragraph 8-31a.
8-34. INDUCTION SYSTEM AIR FILTER.
8-35. REMOVAL OF AIR FILTER.
a. Remove lower engine cowl. (Refer to Paragraph 8-4.)
b.
Remove the filter attachment brackets located on the right, left and aft sides of the filter plenum
by removing the screws on the outside of the plenum and then remove the brackets from the inside of the
plenum.
c. Remove the filter.
8-36. SERVICE INSTRUCTIONS.
After properly determining the filter panel service needs, one of two
basic filter cleaning methods is recommended. The compressed air methods is effective when the major
contamination on the panel is dust. The washing method is effective on carbon, soot and oil laden filters.
Accummulation of exhaust soot (fine carbon particles) collects on the filter and causes a rapid increase in
restriction or short filter life. For best results, visually determine condition of filter and choose either
method. This choice will also depend on the availability of the cleaning equipment. Filters should be
rejected for use if the paper filter material is torn or ruptured or the housing is damaged. The filter gasket
should have no tears and be securely bonded in place. The usable life of the filter should be restricted to
one year or 500 hours, whichever comes first.
a. The compressed air method of cleaning the filter is as follows:
1. With the filter removed, direct a jet of air against the downstream or clean air side of the
filter (opposite to normal airflow).
2. Move the air jet up and down the pleats, moving air jet over the complete filter.
3. Nozzle pressure must not exceed 100 psi and be kept at least one inch away from filter.
Take care that the paper is not ruptured by the nozzle or air jet.
b.
The washing method of cleaning the filter is as follows:
1.
If compressed air is available, blow the filter as given in (a).
Reissued: 10/12/79
POWER
PLANT
2112