jcb G20, Operator'S Manual

Page: 133 / 177

Maintenance
Fault-Finding
126 9831/0650-3 126
Turbocharger wastegate faulty. (Turbocharged ma-
chines only).
Repair or replace wastegate.
Turbocharger malfunction. Replace Turbocharger.
Electrical sensor fault. Check the electrical connections at the sensors.
One or more fuel injector worn or malfunctioning. Check the electrical connections at the injectors.
Engine compression low in one or more cylinders.
Smokes under load at all speeds, but mainly low to
mid speed range.
Check the engine compression.
Table 35. Engine - Exhaust Smoke Excessive (White/Blue Smoke)
Cause Remedy
Improper starting procedure. Verify proper starting procedure.
Stop the engine.
Replace the fuel filters. Operate the engine with a
temporary supply of the correct grade of clean fuel.
Monitor the engine performance.
Fuel is contaminated or incorrect grade diesel fuel
used.
WARNING: Dirty fuel will cause damage to the fuel
injection pump and injectors.
Oil level incorrect. Check oil level.
Diesel or hydraulic oil in sump. Check oil consistency. If oil contamination is suspect-
ed check equipment suck as PTO pump for hydraulic
oil leaks past the seal into the engine. Drain, flush
and fill with clean oil.
Coolant temperature too low (over-cooling) - light
blue or white high speed/light load.
Refer to Table 45.
Electrical sensor fault. Check the electrical connections at the sensors.
One or more engine injector worn or malfunctioning. -
white/ blue smoke at operating temperature.
Check the electrical connections at the injectors.
Coolant leaking into combustion chamber. Refer to Table 43.
Leaking valve stem seals - evident after long idle pe-
riod and then acceleration.
Replace valve seals.
One or more fuel injector worn or malfunctioning. Check the electrical connections at the injectors.
Piston rings not sealing - evident with persistent blue
smoke at all speeds/load.
Check the engine compression.
Table 36. Engine - Will Not Shut Off
Cause Remedy
Stop switch or stop switch electrical system failure. Check the operation of the stop switch. Check the
correct electrical wires for open or short circuits.
Fuel
Table 37. Fuel - Consumption Excessive
Cause Remedy
Additional load on engine. Check/repair accessories and vehicle components.
Refer to the equipment manufacturer's procedures.
Operator technique. Review operation for correct gear shifts, deceleration
and idling.
Check for external leaks at the fuel tank, fuel lines,
filters and lift pump.
Fuel leaks.
WARNING: DO NOT repair defective fuel lines. If
there is a fuel leak remove and discard the neces-
sary components and install new ones.