2004 ISUZU TF SERIES oil

6A – 82 ENGINE MECHANICAL




































9. Compare the width of the Plastigage attached to either the
crankshaft or the bearing against the scale printed on the
Plastigage container.
If the measured value exceeds the limit, perform the
following additional steps.
1. Use a micrometer to measure the crankshaft outside
diameter.
2. Use an inside dial indicator to measure the bearing
inside diameter.
If the crankshaft journal and bearing clearance
exceeds the limit, the crankshaft and/or the bearing
must be replaced.


Crankshaft Journal and Bearing Clearance mm (in)
Standard Limit
0.032 - 0.077
(0.0013 - 0.0030) 0.110 (0.0043)
































Crankpin and Bearing Clearance
1. Clean the crankshaft, the connecting rod, the bearing cap,
and the bearings.
2. Install the bearing to the connecting rod and the bearing
cap.
Do not allow the crankshaft to move when installing the
bearing cap.
3. Prevent the connecting rod from moving.
4. Attach the Plastigage to the crankpin.
Apply engine oil to the Plastigage to keep it from falling.
5. Install the bearing cap and tighten it to the two step of
anglar tihtening method.
Do not allow the connecting rod to move when installing
and tightening the bearing cap.


Connecting Rod Bearing Cap Bolt Torque N·m (kg·m/Ib ft)
4JA1T (L),
4JA1TC 78-88 (8.0/57 – 9.0/65)
1st step ; 29.0–29.2 (3.00/22.0–3.01/22.2)4JH1TC
2nd step ; 45
-60

015LX129
015LX060

ENGINE MECHANICAL 6A – 87

3. Use a feeler gauge to measure the piston ring gap.
If the measured value exceeds the specified limit, the
piston ring must be replaced.


Piston Ring Gap mm (in)
4JA1T (L), 4JA1TC
Standard Limit
1st Compression Ring
2nd Compression Ring0.3-0.3
(0.0118-0.0197)
Oil Ring 0.250-0.450
(0.0098-0.0177) 1.5
(0.059)


4JH1TC
Standard Limit
1st Compression Ring
2nd Compression Ring0.3-0.5
(0.0118-0.0197)
Oil Ring 0.250-0.450
(0.0098-0.0177) 1.5
(0.059)


Piston Ring and Piston Ring Groove Clearance
Use a feeler gauge to measure the clearance between the
piston ring and the piston ring groove at several points around
the piston.
If the clearance between the piston ring and the piston ring
groove exceeds the specified limit, the piston ring must be
replaced.


Piston Ring and Piston Ring Groove Clearance mm (in)
4JA1T (L), 4JA1TC
Standard Limit
1st Compression Ring0.09-0.125
(0.0035-0.0049)
2nd Compression Ring0.05-0.085
(0.0020-0.0033)
Oil Ring 0.03-0.070
(0.0012-0.0028) 0.15
(0.0059)


4JH1TC
Standard Limit
1st Compression Ring0.09-0.130
(0.0035-0.0051)
2nd Compression Ring0.05-0.090
(0.0020-0.0035)
Oil Ring 0.03-0.070
(0.0012-0.0028) 0.15
(0.0059)

015RY00021
015LX025

ENGINE MECHANICAL 6A – 91




IDLER GEAR SHAFT AND IDLER GEAR
Idler Gear "A" Shaft Outside Diameter
Use a micrometer to measure the idler gear shaft outside
diameter.
If the measured value is less than the specified limit, the idler
gear shaft must be replaced.


Idler Gear "A" Shaft Outside Diameter mm (in)
Standard Limit
44.945-44.975
(1.7695-1.7707) 44.845 (1.755)




Idler Gear "A" Shaft inside Diameter
1. Use an inside dial indicator or an inside micrometer to
measure the idler gear inside diameter.


Idler Gear Inside Diameter mm (in)
Standard Limit
45.0-45.03
(1.7717-1.7718) 45.10 (1.7756)
If the clearance between the idler gear shaft outside diameter
and the idler gear inside diameter exceeds the limit, the idler
gear must be replaced.


Idler Gear Shaft and Idler Gear Clearance mm (in)
Standard Limit
0.025-0.085
(0.0010-0.0033) 0.200 (0.0079)















TIMING GEAR CASE COVER
Replace the crankshaft front oil seal if it is excessively worn or
damaged.

Crankshaft Front Oil Seal Replacement
Oil Seal Removal
Use a plastic hammer and a screwdriver to tap around the oil
seal to free it from the gear case cover.
Take care not to damage the oil seal lip surfaces.


020RY00025
014LX022

020R300004

6A – 92 ENGINE MECHANICAL

















Oil Seal Installation
Use the special tool to install the front oil seal.
Front Oil Seal Installer: 5-8840-2361-0
1. With the oil seal attached to the sleeve, insert it into the
front end section of the crankshaft.
2. With the oil seal end section attached securely to the
crankshaft, tighten up the center bolt until the sleeve hits
the front end reference plane of the crankshaft securely.
3. Remove the sleeve.
4. With the seal pressed in, check the dimension of the oil
seal section.
Standard Dimension = 1.0  0.03mm

NOTE:
Install the oil seal after assembling the timing pulley
housing. The oil seal lip section is applied with oil.
Take notice of the press-in direction of the oil seal.

020R300005

ENGINE MECHANICAL 6A – 93
REASSEMBLY
INTERNAL PARTS
MINOR COMPONENT
ROCKER ARM SHAFT AND ROCKER ARM


020RY00029


Reassembly Steps
1.
Rocker arm shaft 5.
Rocker arm
2.
Rocker arm shaft snap ring 6.
Rocker arm shaft spring
3.
Rocker arm 7.
Rocker arm shaft snap ring
4.
Rocker arm shaft bracket









Reassembly
1. Rocker Arm Shaft
1. Position the rocker arm shaft with the large oil hole (4

) facing the front of the engine.
2. Install the rocker arm shaft together with the rocker
arm, the rocker arm shaft bracket, and the spring.
2. Rocker Arm Shaft Snap Ring
3. Rocker Arm
4. Rocker Arm Shaft Bracket
5. Rocker Arm
6. Rocker Arm Shaft Spring
7. Rocker Arm Shaft Snap Ring

014RY00037

6A – 94 ENGINE MECHANICAL
CYLINDER HEAD




RTW46ALF001301


Reassembly Steps
1.
Cylinder head 6.
Valve spring upper seat
2.
Valve spring lower seat 7.
Split collar
3.
Valve stem oil seal 8.
Intake manifold gasket
4. Intake and exhaust valve 9. Intake manifold
5.
Valve spring

ENGINE MECHANICAL 6A – 95
















Reassembly
1. Cylinder Head
2. Valve Spring Lower Seat
3. Valve Stem Oil Seal
1. Apply a coat of engine oil to the oil seal inner face.
2. Use an oil seal installer to install the oil seal to the
valve guide.
Oil Seal Installer: 5-8840-2033-0
4. Intake and Exhaust Valve
1. Apply a coat of engine oil to each valve stem before
installation.
2. Install the intake and exhaust valves.
3. Turn the cylinder head up to install the valve
springs.Take care not to allow the installed valves to
fall free.







5. Valve Spring
Install the valve spring with their fine pitched end (painted)
facing down.

6. Valve Spring Upper Seat









7. Split Collar
1. Use the spring compressor to compress the valve
spring into position.
Spring Compressor: 9-8523-1423-0
2. Install the split collars to the valve stem.
3. Set the split collars by tapping around the head of the
collar with a rubber hammer.





RTW46ASH002301








8. Intake manifold gasket
9. Intake manifold
1. Install the manifold gasket with the end having the
sharp corners facing the rear of the engine.
2. Install the intake manifold to the cylinder head.
3. Tighten the manifold bolt/nuts to the specified torque.


Manifold Bolt/Nut Torque N·m(kg·m/lbft)
Bolt 19 (1.9/14)
Nut 24 (2.4/17)

011RW027
011LX055

014RY00039

ENGINE MECHANICAL 6A – 97


Reassembly
1. Piston
2. Connecting Rod
1. Clamp the connecting rod in a vise.Take care not to
damage the connecting rod.
2. Use a pair of pliers to install the piston pin snap ring to
the piston.





RTW36ASH001801
Install the piston to the connecting rod so that the piston
head front mark (1) and the connecting rod mark (2) are
facing in the same direction.
3. Piston Pin Snap Ring




RTW36ASH001901


4. Piston Pin
1. Apply a coat of engine oil to the piston pin and the
piston pin hole.
2. Use your fingers to force the piston pin into the piston
until it makes contact with the snap ring.



5. Piston Pin Snap Ring
1. Use your fingers to force the piston pin snap ring into
the piston snap ring groove.
2. Check that the connecting rod moves smoothly on the
piston pin.



F06MV015
015R100001