|
Engine Will Not Turn Over
|
| Cranking motor
inoperative or defective |
Replace |
| Battery faulty |
Replace battery |
| Cables and terminals
faulty |
Inspect ground
cable and battery-to-starting switch cable for any faults which may
cause shorting; also inspect for incorrect connections. Replace cables
if necessary |
| Starting switch
defective |
Replace starting
switch |
| Internal seizure |
Hand crank engine
with spark plugs removed and clutch disengaged. If engine does
not turn easily, internal damage is indicated. |
|
Engine Turns But Will Not Start
|
Fuel system faulty
(a) No fuel in tank
(b) Fuel strainer bowl screen clogged
(c) Water in gasoline
(d) No gasoline in carburetor |
(a) Fill tank
(b) Clean bowl
(c) Drain gasoline tank, gasoline strainer and carburetor. Refill
with clean gasoline.
(d) Clean fuel line from tank to carburetor. Clean fuel inlet screen
in carburetor. Check for clogged vent holes in fuel tank cap. |
| Battery charge
low and does not run engine fast enough |
Charge or replace
battery |
Ignition system
faulty
(a) Broken distributor rotor
(b) Moisture in the distributor
(c) Condenser shorted or open
(d) Broken distributor cap
(e) Excessively pitted distributor
(f) Points not properly adjusted
(g) Short or open circuit in distributor
(h) Ignition circuit broken
(i) Wet or fouled spark plugs
(j) Cracked or broken spark plug insulators
(k) Ignition switch inoperative |
(a) Replace rotor
(b) Remove cap and rotor and dry off. Use compressed air to
remove moisture from the distributor.
(c) Replace condenser
(d) Replace cap
(e) Clean contact terminals with fine sandpaper. Blow all sand
out of cap before reinstalling
(f) Readjust points
(g) Correct or replace
(h) Check cable from distributor cap-to-ignition coil and check spark
plugs for correct wiring or loose connections.
(i) Remove spark plugs, wipe off moisture and dry plugs. Remove
carbon. Reset plug gap.
(j) Replace spark plug
(k) Place a jumper wire across the two ignition switch terminals on
the back of the switch. Attempt to start the engine. If
engine starts, the switch is inoperative and must be replaced. |
| Carburetor choked
too much |
Open the choke.
Wait a few minutes before attempting again to start engine. |
| Air intake restricted
or exhaust is clogged |
Service the air
cleaner and clean exhaust system. |
|
Missing and Backfiring But Fails to Start
|
| Water in gasoline |
Drain fuel tank,
fuel bowl and carburetor. Refill with clean gasoline. |
| Air leaks around
intake manifold |
Tighten manifold
stud nuts. Replace gasket if necessary. |
| Improper firing
order |
Check spark plug
cables for correct installation at spark plugs and distributor cap. |
| Distributor not
correctly timed to engine |
Check and adjust
timing. |
| Moisture in the
distributor cap |
Remove cap and
rotor and dry thoroughly. |
| Distributor cap
shorting out |
Check for loose
contact terminals or dirt in cracked cap. |
|
Missing or Cutting Out at High Speed
|
| Distributor breaker
plate not grounded properly |
Check ground lead
wire and screws. |
| Primary lead not
tightened or partially broken |
Check primary lead
wire and screws. |
| Weak point spring
tension |
Adjust point spring
tension or replace points. |
| Spark plugs faulty |
Check plug gap. |
| Point gap incorrect |
Readjust point
gap. |
| Low voltage to
spark plugs caused by defective coil |
Replace coil |
Carburetor:
(a) Float level set to low
(b) Dirt in main jet
(c) Restriction in filter |
(a) Check float
level. Reset if necessary.
(b) Clean out main jet. Replace if necessary.
(c) Clean out fuel inlet filter in carburetor. |
Poor compression:
(a) Heat gasket leaks
(b) Burned valves
(c) Worn piston rings |
(a) Replace head
gasket
(b) Grind valves
(c) Replace piston rings |
|
Excessive Pinging - Detonation
|
Distributor
(a) Point gap incorrect
(b) Spark advanced too far
(c) Fouled spark plugs |
(a)
Readjust point gap.
(b) Check and adjust timing.
(c) Clean plugs and reset gap. |
Carburetor:
(a) Main metering system too lean
(b) Float level set too low |
(a)
Adjust carburetor.
(b) Check float level and reset if necessary. |
| Cylinder
head not bolted down tight |
Torque
cylinder head bolts. |
|
Engine Does Not Operate Smoothly
|
(a) Pitted distributor
points
(b) Cracked distributor cap
(c) Worn or bent distributor shaft
(d) Worn breaker plate hub
(e) Worn distributor cam
(f) Improper point spring tension |
(a) Clean and readjust
points or replace points.
(b) Replace.
(c) Replace.
(d) Replace breaker plate assembly
(e) Replace.
(f) Adjust point spring tension or replace points. |
|
Engine Does Not Develop Full Power
|
Distributor:
(a) Point gap incorrect
(b) Ignition timing is incorrect |
(a) Readjust point
gap.
(b) Check and adjust timing. |
| Low voltage to
spark plugs caused by defective coil |
Replace coil. |
| Fouled spark plugs |
Clean plugs and
reset gap. |
Carburetor:
(a) Float level set too low
(b) Choke plates partially restricted
(c) Restricted throttle linkage |
(a) Check float
level. Reset if necessary.
(b) Reposition choke control linkage.
(c) Repair or replace |
| Insufficient air
to engine |
Service the air
cleaner |
| Late valve timing |
Check and adjust
timing. |
| Air leaks around
intake manifold |
Tighten manifold
or install new gasket if necessary. |
| Exhaust restricted |
Remove restriction. |
| Lack of compression |
See "lack
of compression" in this chart. |
| Governor worn out
or out of adjustment |
Refer to governor
section of "fuel system" |
|
Loss of Oil Pressure
|
| Low lubricating
oil level |
Add sufficient
oil to bring level up to specified mark on level gauge. |
| Clogged oil filter |
Change filter element. |
| Oil leaks |
See "excessive
lubricating oil consumption" in this chart. |
| Engine oil pressure
indicator or line defective |
Replace. |
| Worn main, connecting
rod or camshaft bearings |
Replace. |
| Dirt in oil filter
relief valve or relief valve spring broken |
Clean valve or
replace spring. |
| Oil pump worn |
Repair or replace. |
| Oil diluted or
not as specified |
Change oil regularly
using correct grade specified in Operators Manual. |
|
Lack of Compression
|
| Valves sticking |
Clean valve guides
and stems. Grind valves if needed. |
| Worn pistons, rings
and cylinder walls |
Replace pistons,
rings and cylinder sleeves. |
| Defective cylinder
head gasket |
Replace. |
| Broken valve spring |
Replace |
|
Smoky Exhaust
|
| Engine overload |
Reduce load. |
| Incorrect grade
of lubricating oil |
Use grade of oil
specified in Operators Manual. |
| Worn valve guides,
valve stems, pistons and sticky or worn oil control rings |
Repair or replace. |
| Distributor not
properly timed |
Check and adjust
timing. |
| Choke not fully
open |
Open choke fully. |
|
Excessive Lubricating Oil Consumption
|
| Oil leaks |
Check and service
where necessary; valve covers, tappet cover plate, crank-case front
cover, oile seals at front and rear of crankshaft, oil pan plug, gasket,
oil filter and oil pressure indicator tube. |
| Worn valve guides,
piston rings, pistons and clogged oil control rings |
Replace worn parts. |
| Over-heated engine |
Refer to "engine
overheats" in this chart. |
| Excessive oil poured
into crankcase |
Drain oil.
Add amount specified in operators manual. |
| |
|
|
Excessive Fuel Consumption
|
Distributor:
(a) Point gap incorrect
(b) Ignition timing incorrect |
(a) Readjust point
gap.
(b) Check and adjust timing. |
| Low voltage to
spark plugs caused by defective coil |
Replace coil. |
| Worn or fouled
spark plugs |
Clean plugs and
reset gap. |
Carburetor:
(a) Float level set too high
(b) Leaking needle or seat
(c) Choke plate not fully open |
(a) Check float
level and reset if necessary.
(b) Repair or replace.
(c) Reposition choke control linkage.` |
| Restriction in
air cleaner |
Service the air
cleaner. |
|
Engine Noises
|
| Loose piston pin.
A sharp rap at idling speed. The pin at fault can be found by
short circuiting the spark plugs, one at a time, until the noise stops |
Repair or replace. |
| A flat slap, when
advancing engine speed under load, indicates a loose piston |
Replace piston. |
| A metallic knock
when idling and retarding engine speed, but disappears under load
indicates worn or loose connecting rod bearings. The bearing
at fault can be located by short circuiting the spark plugs one at
a time. The noise will disappear when the cylinder with the
defective bearing is short circuited |
Replace worn bearings. |
|
Bearing Failure
|
| Low oil pressure |
Refer to problem
"loss of oil pressure". |
| Lack of oil |
Maintain proper
oil level. Check for leaks. |
| Engine runs too
hot |
Keep engine at
normal operating temperature. |
| Loose bearings |
Install new bearings |
| Improper lubricating
oil |
Use a suitable
oil of non-corrosive type, correct grade and viscosity. |
| Foreign materials
entering engine |
Use clean oil containers
when filling engine with oil and see that all gaskets on the engine
are in good condition. |
| Oil lines clogged |
Clean all oil passages. |
| Connecting rod
bent |
Align or install
new connecting rod. |
| Crankshaft out
of alignment |
Straighten or install
new shaft. |
|
Valves Sticking
|
| Valve springs weak
or broken |
Install new springs. |
| Gummy deposits
from inferior fuel or oil |
Clean and use proper
fuel or oil. |
| Valve stems scored
or carboned |
Clean. Install
new valves if necessary. |
| Insufficient clearance
between valve stem and guide |
Ream guides for
proper clearance. |
|
Overheating Due to Restricted Air Flow
|
| Bent fan blades |
Straighten and
correct pitch of fan blades. |
| Trash between radiator
fins |
Clean out thoroughly
between radiator fins. Use compressed air. |
| Bent radiator fins |
Straighten bent
fins. |
| Fan housing damaged
or missing |
Repair or install
new fan housing. |
|
Overheating Due to Poor Condition
|
| Restrictions in
radiator core or engine water jacket |
Drain system.
Disconnect hoses and reverse flush the radiator and block. |
| Low coolant level |
Fill cooling system
to proper level. Check for leaks. |
| Pressure cap loose
- coolant escaping |
Tighten pressure
cap. |
| Fan belt slipping
or loose |
Tighten if loose.
Replace belt if greasy, worn or damaged. |
|
Overheating Due to External Leakage
|
| Defective hoses
or connections |
Replace defective
hoses. Check clamps for fatigue and replace as required. |
| Radiator leaks |
Remove radiator.
Test for leaks and solder. |
| Damaged gaskets |
Check for leaks
around water inlet and outlet elbows and cylinder head. Replace
defective gaskets. |
| Cracked or warped
cylinder head |
Replace cylinder
head and gasket. |
| Cracked cylinder
block |
Replace cylinder
block. |
| Defective water
inlet or outlet elbow |
Replace. |
|
Overheating Due to External Leakage
|
| Warped cylinder
head |
Replace cylinder
head and gasket. |
| Blown cylinder
head gasket |
Replace gasket.
(Check crankcase oil for presence of water.) |
| Cylinder head cap
screws not properly torqued |
Torque head cap
screws. |
| Cracked cylinder
wall |
Replace cylinder
block. |
|
|
|
| |
|
