Dark Exhaust Smoke; Oil Pressure Does Not Rise - Isuzu 4JB1 Service Information

Checkpoint
Air cleaner
Injection nozzle
Fuel injection timing
Injection pump
Checkpoint
Engine oil
Oil pressure gauge or
unit
Oil pressure indicator
light
Oil filter
Relief valve and by-
pass valve
Oil pump
Rocker arm shaft
Camshaft
Crankshaft and
bearings

8. DARK EXHAUST SMOKE

Possible cause
Clogged air cleaner element
Injection nozzle injection starting pressure
too low
Improper spray condition
Fuel injection timing improperly adjusted
Defective delivery valve resulting in fuel
drippage after fuel injection
Excessive injection volume

9. OIL PRESSURE DOES NOT RISE

Possible cause
Improper viscosity engine oil.
Insufficient engine oil
Defective oil pressure gauge or unit
Defective indicator light
Clogged oil filter element
Relief valve sticking and/or weak by-pass
valve spring
Clogged oil pump strainer
Worn oil pump related parts
Worn rocker arm bushing
Worn camshaft and camshaft bearing
Worn crankshaft and bearings
SERVICE INFORMATION 00 – 11
Correction
Clean or replace the air cleaner
element
Adjust or replace the injection nozzle
Adjust the fuel injection timing
Replace the delivery valve
Adjust the injection volume
Correction
Replace the engine oil
Correct the engine oil volume
Repair or replace the oil pressure
gauge or unit
Replace the indicator light
Replace the oil filter element or the oil
filter cartridge
Replace the relief valve and/or the by-
pass valve spring
Clean the oil pump strainer
Replace the oil pump related parts
Replace the rocker arm bushing
Replace the camshaft and the
camshaft bearing
Replace the crankshaft and/or the
bearings