4---4
2
3
4
5
6
1
8
7
1. Cylinder head cover
5. Breather oil shield
2. Breather cover
6. Capscrew
3. Breather element
7. Breather assembly
4. Plate
8. O---Ring
Figure 4---5 Engine Crankcase Breather
4.3.8Servicing Glow Plugs
The glow plugs are parallel connected and when
energized, draw 7.5 amps at 12 vdc. When servicing, the
glow plug is to be fitted into the cylinder head to prevent
damage to the glow plug.
Torque value for the glow plugs is 28.9 to 36.2 ft---lb
(4.0 to 5.0 mkg).
Checking for a Defective Glow Plug:
a. One method is to remove the injector and then
energize the glow plug. The glowing tip may then be
observed.
b. Another method is to place an ammeter (or
clip---on ammeter) in series with each glow plug and
energize the plugs. Each plug (if good) should show
amperage draw.
4.4 SERVICING THE ALTERNATOR
4.4.1Preliminary Checks and Tests
NOTE
Before starting the actual electrical test
procedure, the charging system, battery and
wiring should be checked to eliminate possible
problem areas. Figure 1---8 identifies the
terminals on the rear of the alternator.
a. Check the condition and adjustment of belts.
1. Check belt adjustment (refer to section 4.5).
2. Replace any worn or glazed belts.
b. Check to see that all terminals, connectors and
plugs are clean and tight.
1. Loose or corroded connections cause high
resistance and this could cause overcharging, under-
charging or damage to the charging system.
2. Badly corroded battery cables could prevent
the battery from reaching a fully charged condition.
c. Check battery condition and charge if necessary.
A low or discharged battery may cause false or misleading
readings when conducting in---unit tests.
4.4.2Test Tools
A list of the following tools is provided to perform
tests on the alternator and its components.
1. Volt---ohm meter
2. Single---pole, single throw switch
3. 12 vdc lamp
4. Insulated 12 gauge stranded wire
5. Alligator clamp terminals
4.4.3Problem Area Determination
CONDITIONS: Engine running for all tests
(unless otherwise specified).
a. Battery Undercharged
1. Perform open diode---trio test. (Refer to para-
graph 4.4.4.)
2. Perform regulator tests. (Refer to paragraph
4.4.4.) If regulator is O.K., the cause is probably an open
field circuit, and alternator must be removed for repair.
3. Further investigation requires alternator removal
and repair (diodes).
b. Battery Overcharged
1. Perform alternator output test.
(Refer to paragraph 4.4.4.)
2. Regulator shorted. Replace regulator.
4.4.4In---Unit Alternator/Regulator Tests
Test No. 1 --- Open Diode---Trio Test
d
12vdc
TEST LAMP
d
+
TOGGLE
SWITCH
BATTERY
D+
AC TAP
(TACH.)
GROUND
EXCITE
INTEGRAL
REGULATOR
POS+
OUTPUT
(B+)
BATTERY
BLK
VOLTS
B
A
RED
JU1
STEP TEST POINT
INDICATION
1
2
3
A (B+)
B (REG)
BATTERY
VOLTAGE
1.5 TO 3.0 VOLTS
WITH TEST LAMP
ON
13.5 TO15.0 VOLTS
(JUMPER ATTACHED EN-
GINE RUNNING)
A (B+)
SENSE TO
BATTERY
*
*
* JUMPER NOT ATTACHED
**
**
REMOTE BATTERY SENSE ONLY
(TO OIL PRESSURE
SWITCH OR
TOGGLE SWITCH )
Figure 4---6. Open Diode---Trio Test
