Hitachi EX20UR-2 Manual page 382

Extreme
blow-by gas
(Overhaul)
Gas leak from
valve and gasket
(Repair or
replace)
Check bleeder for clogging I I Check injection timing
Clogging (Clean) OK I Faulty (Adjust) OK I
1
Oil moves up or down Check compression pressure
I To fuel system
Extreme
blow-by gas
(Overhaul)
Faulty injection
pump (Bring to
a specialized
shop)
Check fuel for water mon 9
Water mixing
(Change fuel)
Defective
I OK
(Repair or replace)
Check injection timing
Gas leak
from valve
and gasket
(Repair or
replace)
Extreme
blow-by gas
(Overhaul)
OK
Advanced (Adjust) I
OK
Faulty (Bring to a
specialized shop)
1. Oil pump malfunction
2. Loose pipe or crack
3. Wear of sliding part
4. Clogged oil pump
(Overhaul)
5. Defective valve stem
seal (Overhaul)
Gas leak from
valve and
gasket (Repair
or replace)
OK
Faulty exhaust gas
Much white smoke Much black smoke
Check nozzle
Check injection timing
Delayed(Adjust)
Check compression pressure
OK
Check injection pump
1. Disordered valve timing
2. Broken piston ring or
misassembly
3. Wear of camshaft
4. Wear of valve or insert
(Overhaul)
ENGINE/Troubleshooting
Engine knocking
Much oil consumption Much fuel consumtion
Mechanical system
Fuel system
Check for oil leakage Check for fuel leakage
Check oil movement
Check injection timing
Leak
(Re-tighten,
replace packing)
OK
Leak
(Re-tighten.
replace packing)
OK
C FT C
I
Oil stain
(Overhaul)
Faulty (Adjust) OK I
Check nozzle Check oil for quality Check nozzle
Check compression pressure
Defective (Repair
or replace)
I
(:)
K
I Poor quality
(Change to
specified oil)
I
OK j
Defective
(Repair or replace)
OK
Low OK I
Note: Poor fuel is used.
Check oil movement,
up and down
Oil stain (Overhaul)
W05-06-04