Mooney M20R - Page 285

SERVICE
AND
MAINTENANCE
MANUAL
M20R
MOONEY AIRCRAFT
CORPORATION
PROPELLER
GOVEPNOR
TROUBLE
SHOOTING
(con’t.)
TROUBLE
PROB~BLE
CAUSE
REMEDY
Inability
to
attain
proper
RPM
during
Sticky
pillet
valve.
Remove head
and clean
pilot
valve with
static
ground
run:
(con’t.)
i
crocus
cloth.
Maintain
sharp pilot
valve
land
corners.
Check
for
straightness
of
pilot
valve;
if
bent,
replace
valve.
RPM will
not stabilize:
Sludge
iri
governor
pilot
valve
Disassemble
and
clean.
or
relief
~aTve.
Burrs
on
ipilot
valve
lands.
Disassemble
and
clean
with
crocus
cloth.
Backlashi
in
governor
control
Re-rig
or
adjust
control
system.
system.
Short
co~trol
lever
making
fine
Re-rig
control
system.
speed
adfustment
impossible.
Sticloi
reief
valve.
Inspect
fw
buns,
and clean
Erroneou~
reading
tachometer.
Calibrate
or
replace
instrument.
Excessiv~
oil
leakage
in
engine
Refer
to
engine
manual.
transfer
~earing.
nigh
probeller
frictiofi. Refer
to
propeller
overhaul manual.
Governo?
function
upset
by
Repair
engine
for
smooth
operation.
malfunctibning
engine.
Air
trapped
in
propeller.
Cycle
propeller
from MIN
to
MAX
pitch
several times
to
purge
air.
Sticky pili~t
valve.
Remove
head and
pilot
valve.
Clean
away
sludge
and varnish.
Check
speeder
spring
ends for
proper
settings.
Bent
pilot~
valve.
Remove
head
and
replace
pilot
valve.
Excessiv~
internal
leakage
in
Check
rigging
and
make
necessary
part
governor.i
replacements.
Excessive
over-speeding:
Wrong
gc)vernor
setting.
Reset
governor.
Use
test
rig
if
available.
Too
rapidl
throttle
opening.
Advance
throttle
evenly
and
slowly.
Damagedl
or
wrong
gasket
Install
correct
new
gasket.
between
g~overnor
base
and
engine
mounting
pad.
Sticky
governor
pilot
or
relief
Disassemble,
clean and check
for
burrs.
valve.
Replace
bent
pilot
valves.
Erroneou/
reading
tachometer Calibrate
or
replace
instrument.
or
manifold
pressure
gauge.
61-20-90
Rev.
4-95
Island Enterprises