26
PH3300i SM, Rev. 2017-01-20
4.2 Hard Starting
No spark or
weak spark
Good spark plug
Worn or
fouled plug
Abnormal
Normal
Sufficient fuel
Low fuel
No fuel
Fuel present
Low oil
Oil level good
Normal
Low cylinder
compression
Normal
compression
Install the spark plug securely. Engine
should now start and run.
Check for spark (section 4.4.1).
Refer to ignition troubleshooting (section
4.4). Perform tests and repairs.
Remove and inspect the spark plug for a
worn, wet or fouled electrode (section
3.6).
Clean or replace spark plug and perform
any service recommended in (section 3.6)
based on plug deposits.
Make sure the starting and Li-ion
batteries are in good condition and fully
charged (section 3.2). Inspect the battery
terminal connections.
Charge the starting battery using a
recommended charger. Do a load test to
make sure the starting battery maintains
adequate voltage under load. Clean
battery terminals (section 3.2). Replace
any batteries if necessary.
Check the fuel level in fuel tank.
Add fuel and start the engine. If starting
with a dry fuel system, use ≥1.5 gallons.
Loosen the carburetor drain screw to
verify if fuel has reached the carburetor
(section 5.3.1, Fig. 30).
Check the fuel filter (section 3.9), fuel
pump (section 4.6.1), fuel valve, fuel lines
and carburetor for blockage, water in fuel,
and/or a stuck float. Clean or repair as
necessary.
Check the oil level. The low oil sensor can
cause hard starting if the oil is at, or near,
the critically low level.
Add oil (section 3.3) and start the engine.
Perform compression test (section 4.3).
1. Check the valve clearance (section 3.7).
2. Check head gasket.
3. Check for carbon deposits on the valves &
combustion chamber. Clean as necessary.
4. Check the valve cone and seat (section
5.13.3). Lap valves, or replace & regrind as
necessary.
5. Check for worn piston, piston ring or
cylinder (section 5.14.4). Re-ring or
overhaul as necessary.
Choke OK
Verify manual choke is in the correct
position and operating properly.
Use FULL choke for cold engine and
during cold weather, use ½ choke for cold
engine and air temp ≥50°F, use no choke
on a hot engine. Verify proper choke
operation (section 5.1.4).
Choke needs
adjustment