Mooney M20J 1978, Pilot Operating Handbook

Page: 157 / 164

hours, a change t o additive oil should be undertaken with
the is in a n extremely dirty condition,
switch t o additive should be deferred until
engine h a s been overhauled. When from straight
mineral oil t o additive o r compounded oil, after s e v e r a l
hours of operation on mineral oil, take
t h e following steps:
a . Do not mix additive oil and mineral
oil. mineral oil from engine,
filter and fill with additive oil.
Do not operate engine five hours
before again changing oil,
Check oil filter for evidence of sludge or
plugging.
oil and replace oil
element every hours if sludge
Resume normal oil drain periods after
sludge
improve.
engine
addition t o s e r v i c e inspection
procedures needed when you airplane in for
50- hour, 100- hour,
o r
inspections. of
buildup the
system
needs
50-
When
or
adding oil specifies
g r a d e s
of t o
u s e for ambient
t e m p e r a t u r e s .
Average
Grade
Ambient Single Viscosity Viscosity
t o
Below
SAE 50 or 50
40 40
SAE 30 40 or
20
t o the edition of Service Instruc-
tion
11-15-77