Nilfisk-Advance 56507009, Troubleshooting Manual

Page: 28 / 82

28 - FORM NO. 56043129 - SR 1900
Troubleshooting Guide
Symptom
Part1: Diesel engine will crank but not start
Note1: Always use (activate) the glow plugs circuit to start an engine that is not up to its
operating temperature.
Note 2:Before troubleshooting inspect the 10A CB5 circuit breaker.
Glow plug circuit T.S.
Check voltage @ each
glow plug terminal B+ to
Battery ground. Is the
reading close to battery
voltage ?
Test for open circuits in the
Pos.(+) feed wire and glow
plug key switch circuit.
Repair or replace defective
parts.
No
Test each glow plug
for an open circuit. The
resistance spec is .9
Ohms. Do any of the
glow plugs test open ?
Is the fuel tank empty?
Add fuel & air bleed
the fuel system.
Loosen air vent on fuel
filter then next @ the
fuel injection pump
w/engine cranking, but
bleed separately.
Does engine start ?
With the engine
cranking test for 12V
@ the fuel pump.
With the engine cranking
test for 12V (+) @ oil
pressure SW S28,
Gra/Brn wire to Bat. Grd.
Remove fuel line to
injector pump, crank
engine , is fuel
pumping? Test the key SW
accessory output &
circuit wiring to the Com
terminal @ S28. If no
voltage repair or replace
bad parts. If voltage input
is OK replace the oil
pressure switch (S28)
Replace the open
defective glow plug(s).
Does fuel pump run
Replace defective fuel
pump
Loosen injector line
@ injector, crank
engine, check for
fuel.
• See part #2
Governor/fuel control
actuator
troubleshooting.
• See Kubota engine
Service manual check
engine compression,
injector pump, fuel
quality etc. as further
causes.
Fuel System T.S.
No
Yes
Yes
No
Yes
Yes
Test fuel pump B-
Ground wiring & repair
Yes
No
ENGINE SYSTEM
TROUBLESHOOTING GUIDE