Yanmar 3JH4E, Service Manual

Page: 333 / 350

12. Electrical system
313
Inspection
12.7.2 Sender unit for lube oil pressure
gauge
The sender unit for the lube oil pressure gauge has
a mounting seat for mounting on the lube oil filter
bracket. Oil pressure is measured when the oil
enters into the main gallery after being fed from the
lube oil cooler and passing through the oil
pressure control valve. Be sure to mount a
damper when mounting the oil pressure sender
unit.
Lube oil pressure sender unit
Problem Inspection Item Inspection method Corrective action
Lamp not
illuminated when
main switch set to
ON. 1. Oil pressure lamp
blown out.
(1) Visual inspection.
(2) Lamp not illuminated even when
main switch set to ON position
and terminals of oil pressure
switch grounded.
Replace lamp.
2. Operation of oil
pressure switch.
Lamp illuminated when checked as
described in (2) above. Replace oil pressure
switch.
Lamp not
extinguished
while engine
running. 1. Oil level low. Stop engine and check oil level with
dipstick. Add oil.
2. Oil pressure low. Measure oil pressure. Repair bearing wear and
adjust regulator valve.
3. Oil pressure faulty. Switch faulty if abnormal at (1) and
(2) above.
Replace oil pressure
switch.
4. Wiring between
lamp and oil
pressure switch
faulty.
Cut the wiring between the lamp and
switch and wire with separate wire. Repair wiring harness.
Part code No. 119773-91650
Type Resistance switch
Rated voltage DC 12V
Max. operating pressure
0.98 MPa (10 kgf/cm
2
)
Cylinder block
OPTIONAL
Oil pressure
sender
Damper
Oil pressure switch
011076-00E
VDO Made in
Germany
M4 ISO R1/8 Taper
011079-00E