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Engine Troubleshooting

ENGINE TROUBLESHOOTING

ELECTRIC START ENGINE DOES NOT CRANK

  • Battery connections are loose.
  • Battery charge is low or discharged.
  • Battery amperage is low.
  • Starting leads are reversed.
  • Fuse is blown in wiring harness.
  • Key switch is wired wrong.
  • Safety switch is malfunctioning.
  • Wiring harness is wired wrong.
  • Starting cable connectors are loose.
  • Connectors are corroded or worn.
  • Starter/Solenoid is malfunctioning.
  • Electric clutch air gap wrong.
  • Drive pulley is tightened against engine PTO face.
  • Drive belt is wedged on idler pulley.
  • Drive belt tension is adjusted too tight.
  • Combustion chamber is flooded with oil/gas.
  • Lack of oil in crankcase is causing seized engine.
  • Drive shaft coupling is forcing engine shaft against internal thrust face eliminating crankshaft end play.
  • Transmission brakes are too tight.

CRANKS – BUT DOES NOT START

  • Fuel tank is empty.
  • Fuel hose is kinked or pinched.
  • Fuel filter is clogged.
  • Fuel valve is shut off
  • Fuel solenoid is inoperative.
  • LPG Regulator is not opening.
  • Water is in fuel or fuel is stale.
  • Wrong fuel (Diesel).
  • Throttle control is in the stop position.
  • Choke is not fully closed.
  • Choke is on and flooding hot engine.
  • Power take-off clutch stuck is on “on”.
  • Safety interlocks are inoperative.
  • Spark plug wire is disconnected.
  • Spark plug is improperly gapped.
  • Wrong type of spark plug is present.
  • Wiring harness is not connected.
  • Wiring is broken, loose or wrong.
  • Transmission is not in neutral.
  • Electrical clutch is not adjusted.
  • Cranking speed is too slow to start.
  • Spark plug is loose.
  • Compression is low or absent.

RUNS ROUGH & WILL NOT ACCELERATE

  • Spark plug gap is incorrect.
  • Engine is not properly warmed up.
  • Running out of fuel.
  • Low idle is set too low
  • Low idle fuel setting too lean.
  • Electric clutch is dragging.
  • Load is too large on the drive shafts.
  • Crankshaft end play zeroed drive.

BACKFIRES

  • Water is contaminating the fuel.
  • Running out of fuel.
  • Fuel mixture is too rich or too lean.
  • Carburetor fuel solenoid is shorting.
  • Throttle or choke is improperly set.
  • Dirty carburetor needs cleaning.
  • Kill switch is contacting intermittently.
  • Key switch is malfunctioning.
  • Safety interlock(s) are malfunctioning.
  • Faulty fuse is in the unit control box.
  • Leaking or worn valves are present in the engines.
  • Shear pin is partially cut affecting timing.

ELECTRIC SYSTEM PROBLEMS

Charges and gradually discharges
  • Improper ground is causing the battery to lose charge when accessories are activated.
  • Faulty battery will not hold a charge.
Will not charge
  • Regulator-Rectifier has failed.
  • Regulator-Rectifier is not grounded.
  • Flywheel magnet is not charged.
  • Fuse is blown or circuit breaker is open.
Blowing fuses
  • Regulator-Rectifier is burned out.
  • Leads are pinched and are causing shorting.
  • Alternator stator is shorted.
Electric clutch will not engage
  • Wrong Regulator-Rectifier is used.
  • Wiring is wrong or is not grounded.
Engine runs on when switched off
  • Ignition grounding terminal or ground lead is not connected at ignition module.
  • Faulty switch.

STOPS WHILE ON HIGH IDLE

  • Running out of fuel.
  • Running out of oil in the crankcase.
  • Carburetor solenoid is malfunctioning.
  • Key switch is malfunctioning.
  • Safety interlocks is malfunctioning.
  • Spark plug lead is loose.
  • Fuse is blown in control box.
  • Carburetor is out of adjustment.
  • LPG Regulator is malfunctioning.
  • Loss of vacuum to LPG Regulator.
  • Tight drive belt is causing crankshaft bearing to seize.

WON’T RESTART WHEN HOT

  • Overheated - cooling fins are clogged.
  • Overheated - shrouding is blocked.
  • Closed choke is flooding engine.
  • Throttle is not in midway position.
  • Throttle was left in stop position.
  • Carburetor solenoid is malfunctioning.
  • Fouled spark plug.
  • Kill lead is shoring out.
  • Ran out of fuel.
  • Compression is lost.
  • LPG Regulator is not functioning.
  • Vacuum is too low to open LPG Regulator.

CANNOT REACH HIGH SPEED

  • Choke is not completely opened.
  • Throttle control cable clip is loose.
  • Throttle control is improperly installed.
  • Fuel filter or line is clogged.
  • Fuel is running low.
  • Fuel pump is malfunctioning.
  • Foreign material is in carburetor.
  • Carburetor needs adjusting.
  • Spark plug is gapped wrong causing intermittent firing.
  • Drive system is binding up causing load on engine.