Universal M3-20A User Manual

CONTROL PANEL TROUBLESHOOTING
MANUAL STARTER DISCONNECT (TOGGLE SWITCHES)
NOTE: The engine control system is protected by a 20 amop manual resel circuil breaker
located on the engine
as close as possible to the power source.
Problem
Probable Cause VerilicalionJRemedy
PREHEAT depressed, no panel indications
1.
Oil Pressure switch,
1.
Check switches and/or battery connections.
fuel solenoid, electric fuel pump and
preheat solenoid not energized.
2.
20 amp circuit breaker tripped. 2. Reset breaker. If opens again, check preheat solenoid circuit
and run circuit for shorts 10 ground.
START SWITCH DEPRESSED, no starter 1,
Connection to solenoid faulty.
1.
Check connection.
engagement.
2.
Faulty switch 2. Check switch with ohmmeter.
3. Faulty solenoid.
3. Check that 12 vol:ts are present at the solenoid connection.
4. loose battery connections.
4.
Check battery connections.
S.
Low battery. S. Check battery charge state.
NO IGNITION, cranks, does nol start.
1.
Faulty fueling system. 1. Check for fuel.
2.
Check for air in the fuel system. 2. Allow system to bleed.
3,
Faulty fuel lift pump. 3. Replace fuel lift pump.
NDT CHARGING BATIERY
1.
Faulty alternator drive. 1. Clleck tile drive belt and its tension. Be sure the alternator
turns freely. Check for loose connections. Check the
output with a voltmeter. Ensure 12V are present at tile
regulator terminal.
BATIERY RUNS DOWN
1.
Oil pressure SWltcll. 1. Observe if the guages and panel lights are activated when the
engine is not runnmg. Test tile oil pressure switch.
2. High resistance leak to ground.
2. Check the wiring. Insert sensitive (0-.25 amp) meter in battery
lines (Do NOT start engine). Remove connections and replace
after short is located.
3. low resistance leak to ground.
3. Check all wires for temperature riuse to locate the fault.
4.
Faulty alternator. 4. After a good battery charging, disconnect alternator at output
If leakage stops. Remove alternator and benck test. Repair or
replace.
TROUBLESHOOTING WATER TEMPERATURE AND OIL PRESSURE GAUGES
If the gauge reading is other than what is normally indicated
by the gauge when the instrument panel is energized, the first
step
is to check for 12 volts DC between the ignition (B+)
and the Negative (B-)
terminals of the gauge.
Assuming that there
is 12 volts as required, leave the instru-
ment panel energized (key switch on) and perform the
following steps:
1. Disconnect the sender wire
at the gauge and see if the
gauge reads zero, which
is the normal reading for this situa-
tion.
2. Connect the sender terminal
at the gauge to ground and
see if the gauge reads full scale, which
is the normal reading
for this situation.
28
If both of the above gauge tests are positive, the gauge is
undoubtedly OK and the problem lies either with the conduc-
tor from
the sender to the gauge or with the sender.
If either
of the above gauge tests are negative, the gauge is
probably defective and should be replaced.
Assuming the gauge is OK, check the conductor from the
sender to the sender terminal at the gauge for continuity.
Check that the engine block is connected to the ground.
Some starters have isolated ground terminals and if the bat-
tery is connected to the starter (both plus and minus termi-
nals), the ground side will not necessarily he connected
to the
block.

Universal M3-20A Specifications

General

Brand	Universal
Model	M3-20A
Category	Engine
Language	English