section 8 ISUZU TF SERIES 2004 Workshop Manual

6A-18 ENGINE MECHANICAL (6VE1 3.5L)
Fuel Consumption Excessive
Symptom Possible Cause Action
Trouble in fuel system Mixture too rich or too lean due to
trouble in fuel injection system Refer to “Abnormal Combustion"
Fuel cut function does not work Refer to “Abnormal Combustion"
Trouble in ignition system Misfiring or abnormal combustion due
to trouble in ignition system Refer to “Hard Start" or “Abnormal
Combustion"
Others Engine idle speed too high Reset to Section 6E
Returning of accelerator control
sluggish Correct
Fuel system leakage Correct or replace
Clutch slipping Correct
Brake drag Correct
Selection of transmission gear
incorrect Caution operator of incorrect gear
selection
Lubrication Problems
Symptom Possible Cause Action
Oil pressure too low Wrong oil in use Replace with correct engine oil
Relief valve sticking Replace
Oil pump not operating properly Correct or replace
Oil pump strainer clogged Clean or replace strainer
Oil pump worn Replace
Oil pressure gauge defective Correct or replace
Crankshaft bearing or connecting rod
bearing worn Replace
Oil contamination Wrong oil in use Replace with correct engine oil
Oil filter clogged Replace oil filter
Cylinder head gasket damage Replace gasket
Burned gases leaking Replace piston and piston rings or
cylinder body assembly
Oil not reaching valve system Oil passage in cylinder head or
cylinder body clogged Clean or correct

ENGINE MECHANICAL (6VE1 3.5L) 6A-19
Engine Oil Pressure Check
1. Check for dirt, Fuel or water in the engine oil.
a. Check the viscosity of the oil.
b. Check the viscosity of the oil.
c. Change the oil if the viscosity is outside the
specified standard.
d. Refer to the “Maintenance and Lubrication"
section of this manual.
2. Check the engine oil level.
The level should fall somewhere between the
“ADD" and the “FULL" marks on the oil level
dipstick.
If the oil level does not reach the “ADD" mark on
the oil level dipstick, engine oil must be added.
3. Remove the oil pressure unit.
4. Install an oil pressure gauge.
5. Start the engine and allow the engine to reach
normal operating temperature (About 80C).
6. Measure the oil pressure.
Oil pressure should be:
392




550 kPa (56.9




80.4 psi) at 3000 rpm.
7. Stop the engine.
8. Remove the oil pressure gauge.
9. Install the oil pressure unit.
10. Start the engine and check for leaks.

6A-26 ENGINE MECHANICAL (6VE1 3.5L)
Exhaust Manifold LH
Removal
1. Disconnect battery ground cable.
2. Disconnect O
2 sensor connector.
3. Remove torsion bar. Refer to removal procedure in
Front Suspension section.
4. Remove exhaust front pipe three stud nuts from
exhaust side and two nuts from rear end o
f
exhaust front pipe.




RTW36FSH000201
5. Remove heat protector two fixing bolts then the
heat protector.
6. Remove a bolt on engine LH side for ai
r
conditioner (A/C) compressor bracket and loosen
two bolts for A/C compressor then move A/C
compressor to front side.
7. Remove exhaust manifold eight fixing nuts and
remove exhaust manifold from the engine.
Installation
1. Install exhaust manifold and tighten exhaust
manifold fixing nuts to the specified torque with
new nuts.
Torque: 52 N




m (5.3 kg




m/38 lb ft)
2. Install heat protector.
3. Install exhaust front pipe and tighten three stud
nuts and two nuts to the specified torque.
Torque:
Stud nuts: 67 N




m (6.8 kg




m/49 lb ft)
Nuts: 43 N




m (4.4 kg




m/32 lb ft)




RTW36FSH000201
4. Install the torsion bar and readjust the vehicle
height. Refer to installation and vehicle heigh
t
adjustment procedure for front suspension.
5. Set A/C compressor to normal position and tighten
two bolts and a bolt to the specified torque.
Torque : 40 N




m (4.1 kg




m/30 lb ft)
6. Reconnect O
2 sensor connector.
7. Install air cleaner duct assembly.

ENGINE MECHANICAL (6VE1 3.5L) 6A-27
Exhaust Manifold RH
Removal
1. Disconnect battery ground cable.
2. Remove exhaust front pipe three stud nuts and
two nuts then disconnect exhaust front pipe.




RTW36FSH000101
3. Remove steering shaft. Refer to removal
procedure in Steering section.
4. Remove heat protector two fixing bolts then the
heat protector.
5. Remove EGR pipe.
6. Remove exhaust manifold eight fixing nuts then
the exhaust manifold.
Installation
1. Install exhaust manifold and tighten bolts to the
specified torque.
Torque: 52 N




m (5.3 kg




m/38 lb ft)
2. Install EGR pipe.
Torque: 29 N




m (3.0 kg




m/22 lb ft)
3. Install heat protector
4. Install exhaust front pipe and tighten three stud
nuts and two nuts to the specified torque.
Torque:
Stud nuts: 67 N




m (6.8 kg




m/49 lb ft)
Nuts: 43 N




m (4.4 kg




m/32 lb ft)
5. Install steering shaft. Refer to installation
procedure in Steering section.

6A-48 ENGINE MECHANICAL (6VE1 3.5L)
Rear Oil Seal
Removal
1. Remove transmission assembly.

See Transmission section in this manual.
2. Remove flywheel.
3. Remove rear oil seal using a seal remover.
NOTE: Take care not to damage the crankshaft or oil
seal retainer when removing oil seal.
Installation
1. Apply engine oil to oil seal lip and install oil seal
using 5884022860.




015RS017
2. Install flywheel.

Clean tapped holes in the crankshaft.

Remove oil on the crankshaft and flywheel
mounting surface.

Tighten fixing bolts to the specified torque.
NOTE: Do not reuse the bolts and do not apply oil o
r
thread lock to the bolts.
Torque: 54 N




m (5.5 kg




m/40 lb ft)


015RS018
3. Install transmission.

See Transmission section in this manual.
CAUTION: When assembling the engine and
transmission, confirm that dowels have been
mounted in the specified positions at the engine
side. Take care that dowel positions are different
between the manual transmission and the
automatic transmission. Otherwise, the
transmission may be damaged.






012RS009

ENGINE MECHANICAL (6VE1 3.5L) 6A-49
Engine Assembly
Removal

P1010068
1. Disconnect battery ground and positive cable.
2. Remove battery.
3. Make alignment mark on the engine hood and
hinges before removal in order to return the hood
to original position exactly.
4. Remove engine hood.
5. Drain radiator coolant.
6. Disconnect accelerator cable and automatic cruise
control cable from throttle valve on common
chamber.
7. Remove the ECM.

Disconnect the two connectors from the ECM.

. Remove fixing bolts on the common chamber.

Remove fixing bolts for ground cable.
8. Disconnect air duct with air cleaner cover.
9. Remove air cleaner assembly.
10. Disconnect canister vacuum hose.
11. Disconnect vacuum booster hose.
12. Disconnect three engine harness connectors.
13. Disconnect harness connector to transmission (lef
t
front side of engine compartment), disconnect shift
on the fly harness connector from front side o
f
front axle and remove transmission harness
bracket from engine left side.
14. Disconnect ground cable between engine and
frame.
15. Disconnect bonding cable connector on the back
of right dash panel.
16. Disconnect bonding cable terminal on the lef
t
bank.

17. Disconnect starter harness connector from starter.
18. Disconnect generator harness connector from
generator.
19. Disconnect coolant reserve tank hose from
radiator.
20. Remove radiator upper and lower hoses.
21. Remove upper fan shroud.
22. Remove cooling fan assembly four fixing nuts,
then the cooling fan assembly.
23. Move drive belt tensioner to loose side using
wrench then remove drive belt.
24. Remove power steering pump fixing bolts, then
power steering pump. Place the power steering
pump along with piping on the body side.
25. Remove air conditioning compressor fixing bolts
from bracket and place the compressor along with
piping on the body side.
26. Remove four O2 sensor harness connectors (two
each bank) from exhaust front pipe.
27. Remove three exhaust pipe fixing nuts from each
bank.
28. Remove two exhaust pipe fixing nuts from each
exhaust pipe, then move exhaust pipe to rear side
of vehicle.
29. Remove flywheel dust covers.
30. Disconnect two heater hoses from engine.
31. Disconnect fuel hose from right side o
f
transmission.
CAUTION: Plug fuel pipe on engine side and fuel
hose from fuel tank.
32. Remove transmission assembly. Refer to
Transmission section in this manual.
33. Support the engine by engine hoist.
34. Remove two left side engine mount fixing bolts
from engine mount on chassis side.
35. Remove two right side engine mount fixing bolts
from engine mount on chassis side.
36. Remove engine assembly.
Installation
CAUTION: When assembling the engine and
transmission, confirm that dowels have been
mounted in the specified positions at the engine
side. Also take care that dowel positions are
different between the manual transmission and the
automatic transmission. Otherweise, the
transmission may be damaged.

6A-50 ENGINE MECHANICAL (6VE1 3.5L)





012RS009
1. Install engine assembly. Tighten engine mount
fixing bolts to frame to the specified torque.
Torque: 41 N




m (4.2 kg




m/30 lb ft)
2. Reconnect fuel hose to fuel pipe on engine.
3. Install transmission assembly. Refer to
Transmission section in this manual.
4. Reconnect two heater hoses to engine.
5. Install flywheel dust covers.
6. Install exhaust pipe and temporally tighten two
(each bank) rear exhaust flange nuts then tighten
three stud nuts (each bank) between exhaus
t
manifold and exhaust pipe, finally tighten rear side
stud nuts to the specified torque.
Torque: 67 N




m (6.8 kg




m/49 lb ft)






LTW36FSH000101
7. Reconnect O2 sensor connector.
8. Install cooling fan assembly and tighten bolts/nuts
to the specified torque.
Torque: 25 N




m (2.5 kg




m/18 lb ft) for fan pulley
and fan bracket.
Torque : 10 N




m (1.0 kg




m/7 lb ft) for fan and
clutch assembly.
9. Install air conditioner compressor to engine and
tighten to the specified torque.
Torque : 43 N




m (4.4 kg




m/32 lb ft)
10. Install power steering pump, tighten fixing bolt to
the specified torque.
Torque :
M8 bolts : 25 N




m (2.5 kg




m/18 lb ft)
M10 bolts : 43 N




m (4.4 kg




m/32 lb ft)
11. Move drive belt tensioner to loose side using
wrench, then install drive belt to normal position.



850RW001
Legend
(1) Crankshaft Pulley
(2) Cooling Fan Pulley
(3) Tensioner
(4) Generator
(5) Air Conditioner Compressor
(6) Power Steering Oil Pump
(7) Drive Belt

12. Install upper fan shroud.
13. Reconnect radiator upper and lower hoses.
14. Reconnect coolant reserve tank hose to radiator.
15. Reconnect generator harness connector.
16. Reconnect starter harness connector.
17. Reconnect bonding cable terminal on left bank
18. Reconnect bonding cable terminal on the back o
f
right dash panel.

ENGINE MECHANICAL (6VE1 3.5L) 6A-51
19. Reconnect ground cable between engine and
chassis.
20. Reconnect harness connector to transmission and
install transmission harness bracket on engine lef
t
side.
21. Reconnect three engine harness connectors.
22. Reconnect vacuum booster hose.
23. Reconnect canister vacuum hose.
24. Install air cleaner assembly.
25. Reconnect air duct.
26. Reconnect accelerator cable to throttle valve on
common chamber.
27. Install the ECM.

Tighten the four bolts.
Torque : 10 N




m (1.0 kg




m/7 lb ft)

Connect the two connectors.

Tighten the two ground cable bolts.
28. Install engine hood to the origine position.

Refer to installation procedure for Body section
in this manual.

Install accelerator control cable to accelerato
r
cable bracket.

Rotate the ratchet ring in direction an arrow 90

Confirm marking of outer cap must be uppe
r
side.

Slider the lock in direction B.

Confirm ratchet ring is locked.




RTW46ASH000201
Legend
(1) Cable Bracket
(2) Ratchet ring
(3) Outer Cap
(4) Lock
(5) Paint Mark
(6) Arrow Mark

29. Install the cable clips to accelerator control cable.

ENGINE MECHANICAL (6VE1 3.5L) 6A-61
Valve Seat Insert Replacement
1. Arc weld the rod at several points. Be careful not
to damage the aluminum section.
2.
Allow the rod to cool for a few minutes. This will
cause the valve seat to shrink.
3. Strike the rod and pull it out.


014RS015
4. Carefully clean the valve seat press
fit section on
the cylinder head side.
5. Heat the press
fit section with steam or some
other means to cause expansion. Cool the valve
seat with dry ice or some other means.
6. Insert the press
fit section into the valve sea
t
horizontally.
Standard fitting interference: 0.14 mm




0.09 mm
(0.0055 in




0.0035 in)
7.
After insertion, use a seat grinder to grind finish
the seating face. Carefully note the seating angle,
the contact width, and the depression.
8. Lap the valve and the seat.

Reassembly
1. Install valve guide (1) to cylinder head. Apply
engine oil to the outside of the valve guide. Using
valve guide replacer 5
8840
2442
0, drive in a
new valve guide from the camshaft side.
2. Install oil controller (3) and spring lower seat (2).
Using oil controller replacer 5
8840
0623
0, drive
in a new oil controller.




014RW058
3. Install valve to valve guide. Before install valve
guide apply engine oil to the outside of the valve
stem.
4. Install valve spring to cylinder head. Attach the
valve spring to the lower spring seat. The painted
area of the valve spring should be facing
downward.


014RS020

ENGINE MECHANICAL (6VE1 3.5L) 6A-89


012RS005
NOTE: For information on piston diameter, please refer
to the section "Inspection of the Piston and Connecting
Rod Assembly" in this manual.
 The "Grade" mark (1) is stamped at the
position illustrated.





012RS006
Reassembly
1. Install cylinder block.
2. Install crankshaft.
 Install the main bearings to the cylinder block
and the main bearing caps.
 Be sure that they are positioned correctly.

Apply new engine oil to the upper and lower
main bearing faces.
NOTE: Do not apply engine oil to the bearing back
faces.






015RS012
Legend
(1) Number 1 and 4 main bearing upper and lower.
(2) Number 2 and 3 main bearing upper.
(3) Number 2 and 3 main bearing lower.

 Carefully mount the crankshaft.
 Apply engine oil to the thrust washer.
 Assemble the thrust washer to the No. 3
bearing journal. The oil grooves must face the
crankshaft.





015RS013
3. Install rear oil seal retainer.
 Remove oil on cylinder block and retainer fitting
surface.

Apply sealant (TB1207B or equivalent) to
retainer fitting surface as shown in illustration.
 The oil seal retainer must be installed within 5
minutes after sealant application before the
sealant hardens.