EM-50 ENGINE MECHANICAL - Cylinder Block
INSPECTION AND REPAIR OF CRANKSHAFT
INSPECT CRANKSHAFT FOR RUNOUT
(a) Place the crankshaft on V-blocks.
(b) Using a dial indicator, measure the circle runout a t
the center journal.
Maximum circle runout: 0.06 mm (0.0024 in.)
If the circle runout is greater than maximum, replace the
crankshaft.
Crank Journal Diameter 2. INSPECT MAIN JOURNALS AND CRANK PINS
(a) Using a micrometer, measure the diameter of each
main journal and crank pin.
Main journal diameter:
STD 61.985 - 62.000 mm
(2.4403 - 2.4409 in.)
-
U/S 0.25 61.745 61.755 mm
-
(2.4309 2.4313 in.)
-
U/S 0.50 61.495 61.505 mm
(2.4211 - 2.4215 in.)
Crank pin diameter:
Crank Pin Diameter
STD 54.988 - 55.000 mm
(2.1649 - 2.1654 in.)
-
U/S 0.25 54.745 54.755 mm
(2.1553 - 2.1557 in.)
-
U/S 0.50 54.495 54.505 mm
(2.1455 - 2.1459 in.)
If the diameter is not as specified, check the oil clearance.
(b) Check each main journal and crank pin for taper and
out-of-round as shown.
Maximum taper and out-of-round: 0.02 mm
(0.0008 in.)
If the taper or out-of-round is greater than maximum,
grind or replace the crankshaft.
IF NECESSARY, GRIND AND HONE MAIN JOURNALS
AND/OR CRANK PINS
Grind and hone the main journals and/or crank pins to the
finished undersized diameter (See procedure step 2).
Install new main journal and/or crank pin undersized bear-
ings.
ASSEMBLY OF CYLINDER BLOCK
The connecting rod cap nut tightening torque has been
changed as follows:
Torque:
Previous 1st 550 kg-cm (40 ft-lb, 54 N-m)
2nd 90" turns
t
New 1st 350 kg-cm (25 ft-lb, 34 N-m)
2nd 120" turns
Downloaded from www.Manualslib.com manuals search engine
Downloaded from www.Manualslib.com manuals search engine
TG2 TURBOCHARGER SYSTEM - Description
DESCRIPTION
Water Cooling Channel
Full-Floating Bearing
Impeller Wheel
\ /
Wheel
\
Waste Gate Valve
Full-Floating Bearing
Svstems which increase the amount of air sent air to the engine. This allows a proportional in-
to the engine are either turbocharger type (using crease in thefuel that can be burned and hence
exhaust gas to turn the turbine) or supercharger raises the potential power output.
type (using the engine crankshaft, etc. to mechani- In other words, by installing a special turbo-
cally turn the pump, etc.). For LAND CRUISER charger and providing a higher air than usual,
and 4 RUNNER 2L-T engine, the turbocharger engine output can be increased by increasing the
type has been adopted. average combustion pressure without increasing
The turbocharger is a device which increases the engine speed.
engine output by introducing a greater amount of
Downloaded from www.Manualslib.com manuals search engine
TURBOCHARGER SYSTEM - Description TC-3
Turbocharger
Operation of Turbocharger Waste Gate Valve
Exhaust gas acts on the turbine wheel inside the If the turbocharged air pressure exceeds the
turbine housing, causing it to revolve. When the prescribed air pressure, the flow of exhaust gas
turbine wheel revolves, the impeller wheel which is by-passes the turbine, controlling turbine wheel
located on the same shaft also revolves, compres- revolutions and turbocharged air pressure. This
sing the intake air which has passed through the air by-pass valve which controls the quantity of ex-
cleaner. When expelled from the compressor hous- haust gas flowing to the turbine is called the waste
ing the compressed air i s supplied to the cylinders: gate valve. When the charged air pressure exceeds
When the engine speed increases, the exhaust gas the prescribed pressure, the actuator operates, the
volume increases and the turbine wheel revolutions waste gate valve opens and part of the exhaust gas
increase (approx. 20,000 - 115,000 rpm), thus the by-passes the turbine. This causes a drop in the
turbocharged air pressure grows greater and engine turbine revolution rate and controls the charged air
output increases. pressure within the prescribed limits.
Downloaded from www.Manualslib.com manuals search engine
TC-4 TURBOCHARGER SYSTEM - Precautions
PRECAUTIONS
Do not stop the engine immediately after pulling a trailer
or high speed or uphill driving. Idle the engine for 20 -
120 seconds, depending on the severity of the driving con-
dition.
Avoid sudden racing or acceleration immediately after
starting a cold engine.
I f the turbocharger is defective and must be replaced, first
check for the cause of the defect in reference to the fol-
lowing items and replace parts i f necessary:
Engine oil level and quality
Conditions under which the turbocharger was used
Oil lines leading to the turbocharger
No! / i Use caution when removing and reinstalling the turbo-
charger assembly. Do not drop it or bang it against any-
thing or grasp it by easily-deformed parts, such as the
actuator or rod, when moving it.
Before removing the turbocharger, plug the intake and
exhaust ports and oil inlet to prevent entry of dirt or other
foreign material.
I f replacing the turbocharger, check for accumulation of
sludge particles in the oil pipes and, i f necessary, replace
the oil pipes.
Completely remove the gasket adhered to the lubrication
oil pipe flange and turbocharger oil flange.
If replacing bolts or nuts, do so only with the specified
new ones to guard against breakage or deformation.
If replacing the turbocharger, put 20 cc (1.2 cu in.) of oil
into the turbocharger oil inlet and turn the impeller wheel
by hand to spread oil to the bearing.
If overhauling or replacing the engine, cut the fuel supply
after reassembly and crank the engine for 30 seconds to
distribute oil throughout the engine. Allow the engine to
idle for 60 seconds.
Downloaded from www.Manualslib.com manuals search engine
TURBOCHARGER SYSTEM - Precautions, Troubleshooting TC-5
11. I f the engine is running with the air cleaner, case cover and ,
hose removed, entry of foreign particles will damage the
wheels which run at extremely high speed.
TROUBLESHOOTING
HINT: Before troubleshooting the turbocharger, first
check the engine itself. (Valve clearance, engine compres-
sion, injection timing etc.)
INSUFFICIENT ACCELERATION, LACK OF POWER OR
EXCESSIVE FUEL CONSUMPTION
(Possible Cause) (Check Procedure and Correction Method)
I 1. TURBOCHARGING PRESSURE TOO
LOW t Check turbocharging pressure. (See page TC-8)
Turbocharging pressure:
-
0.61 0.81 kg/cm2
(8.7 - 11.5 psi, 60 - 79 kPa)
I f the pressure i s below specification, begin
diagnosis from item 2.
Check intake air system, and repair or replace parts
as necessary. (See page TC-8)
3. LEAK I N IN Check intake air system, and repair or replace parts
as necessary. (See page TC-8)
4. RESTRICTED EXHAUST SYSTEM Check exhaust system, and repair or replace parts as
necessary. (See page TC-8)
5. LEAK IN EXHAUST SYSTEM Check exhaust system, and repair or replace parts as
necessary. (See page TC-8)
6. ERRATIC TURBOCHARGER
OPERATION
-' Check rotation of impeller wheel. I f it does not turn
or turns with a heavy drag, replace the turbocharger
assembly.
Check plays of turbine shaft. (See page TC-12)
1
I
Axial play: 0.13 mm (0.0051 in.) or less
Radial play: 0.18 mm (0.0071 in.) or less
I f not within specification, replace the turbocharger
assembly.
Downloaded from www.Manualslib.com manuals search engine
