Engine Diagnostics - Westpro Westinghouse WH3250 Series Service Manual

ENGINE DIAGNOSTICS

Engine Fails to Start
Check Oil Level
Check Fuel Level
Check Fuel Shut-off Valve Open
Confirm Choke in On Position
Check Spark Plug
Dry Spark Plug =
Check Carburetor
Fuel Cutout Solenoid
Wet Spark Plug =
Check Ignition System
Check Spark Plug Gap
Plug Condition Good =
Re-Gap Spark Plug
Plug Condition Dirty or Worn =
Replace Spark Plug
Check Ignition for Spark
Bright Blue Spark =
Reinstall Plug
Weak Dull Spark =
Pull Coil & Check Resistance
Primary Coil = 0.8-1.0 Ohms
Secondary Coil = 5.9-7.1 Ohms
(measure at spark plug lead)
Replace Coil, if Necessary
Reinstall Coil with Proper
Coil / Flywheel Air Gap
Set gap to .008-.016 in.
(.2-.4mm)
Reinstall Plug
Drain Oil and
Check Low Oil Switch
Connection and Continuity
(Y ellow Wire on Side of Engine)
Check Flywheel Woodruff Key
Repair or Replace Key
Perform Engine Compression T est
TROUBLESHOOTING
Engine Fails to Crank
Using Electric Starter
Check Recoil for
Mechanical Binding
Check Battery Voltage
Higher than 12.5 Volts =
Check Voltage Across Components
Less than 12.5 Volts =
Charge or Replace Battery
Check Voltage Across Components
Check Battery Connections
Check Leads on Proper Post
Check Leads are Clean & Tight
Check Voltage Across Components
are Within .5V of Battery Voltage
Replace Out of Spec Components
Check Engine Control Switch
Voltage
Drop in Start Position
Check Battery Post / Solenoid
Voltage Drop
Check Battery Post / Starter Lugs
Voltage Drop
NOTE: Generator has Charging
Coil During Operation; Replace
Coil if Repeated Battery Discharge
Engine Speed Unstable
Check Spark Plug & Gap
Check Ignition for Spark
Adjust Coil Air Gap
Check Spark Arrestor
Check Muffler Blockage
Check Governor
Frequency = 60 Hz + 3
Check Governor Assembly
Adjustment
Figure 8-4
Engine Starts
Then Shuts Down
Check Fuel Level
Check Fuel Quality
Confirm Choke in Off Position
Check Oil Level
Check Ignition for Spark
Check Spark Plug & Gap
Adjust Coil Air Gap
Check Fuel Line & Blockage
Check Carburetor
Check Spark Arrestor
Check Muffler Blockage
Engine Smokes
Start Engine
Warm to Operating T emperature
Observe Smoke Color
White Smoke =
Poor Fuel Quality
Black Smoke =
Check Choke Operation
Check Ignition System
Blue Smoke =
Check Oil in Fuel
Check Oil Overfilled
Check Worn Piston Rings
Perform Engine Compression T est
Engine Runs Rough
Check Fuel Level
Check Fuel Quality
Confirm Choke in Off Position
Check Air Cleaner
Check Ignition for Spark
Check Spark Plug & Gap
Check Fuel Line & Blockage
Check Carburetor
Check Spark Arrestor
Check Muffler Blockage
Check Valve Adjustment
Perform Engine Compression T est
Recoil Not Operating
Recoil Locked =
Replace Recoil Assembly
(see Manual Section
"Recoil Starter")
Check Recoil for
Mechanical Binding
Rope Not Retracting =
Replace Recoil Assembly
(see Manual Section
"Recoil Starter")
8-5