Onan NHE Service Manual

TROUBLESHOOTING THE NHE CONTROL
Trouble
Engine
Does
Not Crank
(cont.)
Engine
Cranks But
Does Not Start
Engine Starts
But Stops
When Start
Switch is
Released
Possible Cause
5. Connect a voltmeter bitween
terminal S on the start solenoid
and ground. Check for battery
voltage when
S1 is placed in Start
position.
If voltage is present,
fault is due
to:
a. K1 relay not grounded,
b. defective K1 relay, or
c. defective starter
6. If voltage is not present as described
in step
5 test, fault is due to:
a. open circuit between K1 relay
and control PC board, or
b. defective control PC board.
1. Faulty ignition due to worn
or fouled spark plugs, worn
ignition points, incorrect
ignition timing, or faulty
plug wires.
2. Faulty fuel system due to
sticking choke, faulty fuel
pump, or carburetor mixture
screws incorrectly adjusted.
3. Connect a voltmeter between
positive (+)terminal on
coil and ground. Check for
battery voltage when S1 is
placed in the
Start position.
If the voltage is not present,
fault is due to:
a. open circuit between coil and
control
b. defective control PC board.
~~ ~
1. Low dlpressure switch not closing
due to:
a. low oil level
b. open circuit between switch and
control
c. defective low oil pressure switch
d. low oil pressure.
2. Output voltage from generator
not being supplied to control
due to:
a. defective charge resistor
b. open circuit in wiring between
generator and control.
c. defective bridge rectifier
d. no output voltage from generator.
Corrective Action
5a. Tighten solenoid bracket mounting
5b. Replace
K1 start solenoid.
5c. Refer to Electric Starter section for
screw
test and service procedures.
6a. Check for continuity and correct if
6b. Replace control PC board.
circuit is open.
1. Refer to Ignition System section
section for test and
service procedures.
2. Refer to Fuel System
section for test and service
procedures.
3a. Check for continuity and correct
correct
if circuit is open.
3b. Replace control PC board.
laycheck oil level and add oil if low.
1 b. Check for continuity and correct if
circuit is open.
1 c. Replace low oil pressure switch.
Id. Refer to Lubrication system section
for test and service procedures.
2a. Test
R6 charge resistor (2.5 ohm)
and replace if defective.
2b. Check for continuity and correct
if circuit is open.
2c. Refer
to Generator section
for test and service procedures.
2d. Refer
to Generator section
for test and service procedures.
7-5
Redistribution or publication of this document
by any means, is strictly prohibited.
Redistribution or publication of this document
by any means, is strictly prohibited.

Onan NHE Specifications

General

Brand	Onan
Model	NHE
Category	Portable Generator
Language	English