Universal M3-20A User Manual

Problem
Battery runs down.
Engine overheats.
NOTE: Shut engine down immediately.
Exhaust smoking problems
Transmission will not shift in or out
of gear, or drive the vessel.
Excessive vibration
ENGINE TROUBLESHOOTING
Probable Cause
1. Oil Pressure switch.
2. High resistance leak to ground.
3. Low resistance leak.
4. Alternator.
5. Poor battery connections.
1. Raw water not circulating.
2.
Coolant not circulating.
1. Blue smoke.
2. White smoke.
3.
1.
1.
2.
Black or gray smoke.
Transmission faHure.
Faulty engine alignment
Cutless bearings. support strut and
propeller could all be suspect.
MARINE POWER
.~
27
VerificalionJRemedy
1.
Observe if gauges and panel lights are activated when engine is
not running. Test the oil pressure switch.
2.
Check wiring. Insert sensitive (0 •. 25 amp) mete in battery lines.
(Do not start engine.) Remove connections and replace after short
is located.
3.
Check all wires for temperature fise to locate the fault.
4.
Disconnect alternator at output. after a good battery charging. If
leakage stops, remove alternator and bench test. Repair or replace.
5. Check cable connections at battery.
1. Broken or loose belt at raw water pump
2. Raw water pump failure. Check impeller - replace.
2a. Obstruction at raw water intake or raw water filter.
2b. Thermostat - remove and test in hot water.
Replace thermostat.
2c. Loss of coolant - check hoses. hose clamps. drain plug, etc. for
leaks.
2d. Broken or loose belts - tighten/replace.
2e. Air leak in system; run engine and open cooling system petcocks,
heat exchanger, manifold. etc. to bleed air. Add coolant as needed.
1.
Incorrect grade of engine oiL
la. Crankcase is overfilled with engine oil (oil is blowmg out through
the exhaust).
2. Engine is running cold.
2a. Faulty injector or incorrect injector timing.
3.
Improper grade of fuel.
3a. Fuel bum incomplete due to high back pressure :n exhaust or
insufficient air for proper combustion (Check for restrictions in
exhaust system; check air intake).
3b. Improperly timed fuel system, misadjusted valves or poor
compression.
3e. Lack of air - check air intake and air filter. Check for proper
ventilation.
3d. Overload.
3e. Propeller.
la. Check cable connections at steering station and at
transmission lever.
lb. Check transmission fluid.
1&. Check shaft couplings or engine damper plate.
ld. Check engine's damper plate.
1.
Check the shaftJtransmlssion coupling.
la.lnspect all engine mounts,
2.
Inspect propeller and shaft.

Universal M3-20A Specifications

General

Brand	Universal
Model	M3-20A
Category	Engine
Language	English