Onan MEP-003A - Page 46

TM 5-6115-585-34
NAVFAC
P - 8-623-34
TO
-
35C2-3-455-2
TM
-
05684C
/
05685B
-
34
CHAPTER 3
MAINTENANCE
OF
COOLING
SYSTEM
Section
1.
DESCRIPTION
AND
FUNCTION
3-1 . GENERAL .
The
engine
has
a pressure
air
cooling
system
. Fins
on
the
engine
blower
draw
air
into
the
front
of the
engine
housing
and
force
it past
the
cylinders
and
out
the
right
side
of the
engine
. A separate
blower
on the
generator
rotor
draws
air
into
the
rear
of the
gener
ator
and
forces
it
out
openings
near
the
engine
.
The
engine
air
outlet
uses
a
shutter
assembly
to
control
engine
temperature
.
A
thermostatic
element
controls
shutter
opening
which
limits air
flow
when
the
engine
is
cold
.
When
the
engine
air
temperature
reaches
approximately
120
°
F
,
(
49
°
C
)
the
shutters
begin
to
open
.
The
shutters
are
completely
open
at
140
°
F
(
60
°
C )
under
full
rated
load
.
Section
II
.
MAINTENANCE
3-2 . ENGINE COOLING SYSTEM .
d
.
Repair
.
a . Inspect
on
Equipment
( see
figure
3-1
) .
( 1 ) Shutter Assembly . Inspect shutter assembly
( 1 ) for physical damage . Check for debris within as
sembly . Check for smooth operation of shutters when
moved manually . Check for chipped paint or rusting .
( 1 )
Shutter
Assembly
. Refer
to
Operator
and
Organizational
Maintenance
Manual
to
remove
and
replace
defective
components .
Repair
physical
damage
by
removing
the
dents
, welding
breaks
in shutter
as
sembly
box
. Clean
repaired
area
with
dry
cleaning
solvent
Federal
Specification
P - D - 680
. Paint
as
re
quired
with
MIL
- T - 704
, type
A , se
migloss
, olive
drab
,
color
no
.
24087
.
( 2 ) Bracket Assembly . Inspect that brackets ( 2 )
are securely mounted to shutters ( 3 ). Check that
bracket bearings are not excessively worn . Refer to
Operator
and Organizational Maintenance
Manual .
( 2 )
Bracket
Assemblies
.
Replace
bracket
( 2 ) or
bearings
if
required
.
( 3 ) Shutters . Bump out dents and straighten shut
ters ( 3) if required . Clean with dry cleaning solvent
and repaint
if
necessary
.
( 3 ) Shutters . Inspect shutters ( 3 ) for physical
damage and secure mounting to brackets ( 2 ) .
( 4 ) Air Housing Panel and Door . Inspect air hous
ing panel and door ( 5 ) for physical damage .
( 5 ) Grille . Inspect grille ( 6 ) for secure mounting
to blower housing ( 7 ) . Check for physical damage .
( 4 ) Air Housing Panel and Door . Clean air hous
ing panel and door ( 5 ) with dry cleaning solvent and
repaint
if
necessary
.
( 5 ) Grille
.
Straighten any
bent
wires
on
grille
( 6 ) or
weld
if
required
to
repair
.
(6 ) Blower Housing . Inspect blower housing ( 7)
for physical damage . Check that blower housing is
securely mounted to engine .
( 6 ) Blower . Housing . Bump out dents in blower
housing
( 7 ) , repair cracks with welds if
necessary
and clean with dry cleaning solvent . Paint as required .
b
.
Removal
.
Refer
to
Operator
zational
Maintenance
Manual
.
and
Organi
c .
Disassemble .
Disassemble
repairable com
ponents
of
the
cooling
system
per
Operator
and
Organizational
Maintenance
Manual
.
e
.
Installation
.
Install
engine
cooling
system
per
Operator
and
Organizational
Maintenance
Manual
.
WARNING
3-3 . HIGH TEMPERATURE CUTOUT SWITCH .
a
.
Remove
(
see
figure
3-1
)
.
( 1 ) Disconnect electrical leads ( 10 ) .
Solvent , Dry Cleaning P - D - 680 , Type II is
flammable
and
moderately toxic
to skin ,
eyes
and respiratory tract . Eye and skin protec
tion required . Good general ventilation is
normally adequate
.
( 2 ) Straighten locking tab ( 12 ) and remove switch
( 11 ) .
Change
3
3-1