________________________________________________________________________________
Kubota B26, B2601, B2620, B2630 - Engine Maintenance
Kubota D1105 3-cyl diesel engine used in B26, B2601, B2620, B2630
tractors.
Kubota B26, B2601, B2620, B2630 Engine -
Checks and Adjustments
Compression Pressure
Operate the D1105 engine until it is warmed up. Stop the engine. Remove
the air cleaner, the muffler and all glow plugs (or nozzles). Set a
compression tester with the adaptor to the glow plug hole (or nozzle
hole). Nozzle Hole: Adaptor H / Glow Plug Hole: Adaptor L. After making
sure that the stop lever is set at the stop position (non-injection),
operate the engine with the starter and measure the compression
pressure. Repeat steps 4 and 5 for each cylinder. If the measurement is
below the allowable limit, apply a small amount of oil to the cylinder
wall through the glow plug hole (or nozzle hole) and measure the
compression pressure again. If the compression pressure is still less
than the allowable limit, check the top clearance, valve clearance and
cylinder head. If the compression pressure increases after applying oil,
check the cylinder wall and piston rings.
Valves
Valve Clearance - Valve clearance must be checked and adjusted when
engine is cold. Remove the head cover, the glow plugs and the timing
window cover on the clutch housing. Align the "1TC" mark line on the
flywheel and center of timing window so that the No. 1 piston comes to
the compression top dead center. Check the following valve clearance
marked with using a feeler gauge. If the clearance is not within the
factory specifications, adjust with the adjusting screw. The "TC"
marking line on the flywheel is just for No. 1 cylinder. There is no
"TC" marking for the other cylinders. No. 1 piston comes to the T.D.C.
position when the "TC" marking line is aligned with center of timing
window on front case. Turn the flywheel 0.26 rad (15 degrees) clockwise
and counterclockwise to see if the piston is at the compression top dead
center or the overlap position. Now readjust the valve clearance.
Finally turn the flywheel 6.28 rad (360 degrees) and align the "TC"
marking line and the center of timing window. Adjust all the other valve
clearance as required. After turning the flywheel counterclockwise twice
or three times, recheck the valve clearance, firmly tighten the lock nut
of the adjusting screw. Valve Seat Tightness - Set the injection nozzle
to a nozzle tester. Raise the fuel pressure, and keep at 12.75 MPa (130
kgf/cm2, 1849 psi) for 10 seconds. If any fuel leak is found, replace
the nozzle piece.
Kubota B26, B2601, B2620, B2630 - Lubrication
System
Changing Engine Oil
Before changing oil, be sure to stop the D1105 engine. Start and warm up
the engine for approx. 5 minutes. Place an oil pan underneath the
engine. To drain the used oil, remove the drain plug at bottom of the
engine and drain the oil completely. Screw in the drain plug. Fill new
oil up to upper notch on the dipstick. When using an oil of different
manufacturer or viscosity from the previous one, remove all of the old
oil. Never mix two different type of oil. Use the proper SAE Engine Oil
according to ambient temperatures. Engine oil capacity - 3 L.
Engine Oil Pressure
Remove the engine oil pressure switch, and set an oil pressure tester.
Start the engine. After warming up, measure the oil pressure of both
idling and rated speeds. If the oil pressure is less than the allowable
limit, check the following: engine oil insufficient, oil pump damaged,
oil strainer clogged, oil filter cartridge clogged, oil gallery clogged,
excessive oil clearance. After checking the engine oil pressure, tighten
the engine oil pressure switch to the specified torque.
Replacing Engine Oil Filter Cartridge
Remove the oil filter cartridge with the filter wrench. Apply a slight
coat of oil onto the cartridge gasket. To install the new cartridge,
screw it in by hand. Over tightening may cause deformation of rubber
gasket. After the new cartridge has been replaced, the engine oil
normally decrease a little. Thus see that the engine oil does not leak
through the seal and be sure to read the oil level on the dipstick.
Then, replenish the engine oil up to the specified level.
Oil Pump
Rotor Lobe Clearance - Measure the clearance between lobes of the inner
rotor and the outer rotor with a feeler gauge. If the clearance exceeds
the factory specifications, replace the oil pump rotor assembly.
Cylinder I.D: 78.000 to 78.019 mm / 3.0709 to 3.0716 in. Oversized
cylinder liner I.D: 78.500 to 78.519 mm / 3.0906 to 3.0912 in. Clearance
between Outer Rotor and Pump Body - Measure the clearance between the
outer rotor and the pump body with a feeler gauge. If the clearance
exceeds the factory specifications, replace the oil pump rotor assembly.
Clearance between outer rotor and pump body - 0.100 to 0.180 mm /
0.00394 to 0.00708 in. Clearance between Rotor and Cover - Put a strip
of plastigauge onto the rotor face with grease. Install the cover and
tighten the screws. Remove the cover carefully, and measure the amount
of the flattening with the scale and get the clearance. If the clearance
exceeds the factory specifications, replace the oil pump rotor assembly.
Clearance between rotor and cover - 0.025 to 0.075 mm / 0.00099 to
0.0029 in.
Kubota B26, B2601, B2620, B2630 - Cooling
System
Fan Belt and Radiator
Fan Belt Tension - Measure the deflection, depressing the belt halfway
between the fan drive pulley and dynamo pulley at specified force (98 N,
10 kgf, 22 lbf). If the measurement is not within the factory
specifications, loosen the dynamo mounting screws and relocate the
dynamo to adjust. Fan Belt Damage and Wear - Check the fan belt for
damage. If the fan belt is damaged, replace it. Check if the fan belt is
worn and sunk in the pulley groove. If the fan belt is nearly worn out
and deeply sunk in the pulley groove, replace it. Radiator Cap Air
Leakage - Set a radiator tester and adaptor on the radiator cap. Apply
the specified pressure 88 kPa (0.89 kgf/cm2, 12 psi), and measure the
time for the pressure to fall to 59 kPa (0.61 kgf/cm2, 8.6 psi). If the
measurement is less than the factory specification, replace the radiator
cap. Radiator Water Leakage - Pour a specified amount of water into the
radiator. Set a radiator tester and an adaptor and raise the water
pressure to the specified pressure. Check the radiator for water leaks.
For water leak from the pinhole, repair with the radiator cement. When
water leak is excessive, replace the radiator.
Thermostat Valve Opening Temperature
Suspend the thermostat in the water by a string with its end inserted
between the valve and seat. Heating the water gradually, read the
temperature when the valve opens and leaves the string. Continue heating
and read the temperature when the valve opens approx. 8 mm (0.3 in.). If
the measurement is not within the factory specifications, replace the
thermostat.
Flush Cooling System and Changing Coolant
Stop the D1105 engine and let cool down. To drain the coolant, open the
radiator drain cock, and remove radiator cap. The radiator cap must be
removed to completely drain the coolant. After all coolant is drained,
close the drain plug. Fill with clean water and cooling system cleaner.
Follow directions of the cleaner instruction. After flushing, fill with
clean water and anti-freeze until the coolant level is just below the
port. Start and operate the engine for few minutes. Stop the engine.
Check coolant level and add coolant if necessary. Install the radiator
cap securely.
Kubota B26, B2601, B2620, B2630 - Fuel System
Fuel Injection Pressure
Set the injection nozzle to a nozzle tester. Slowly move the tester
handle to measure the pressure at which fuel begins jetting out from the
nozzle. If the measurement is not within the factory specifications,
replace the adjusting washer in the nozzle holder to adjust it. Pressure
variation with 0.01 mm (0.0004 in.) difference of adjusting washer
thickness: Approx. 235 kPa (2.4 kgf/cm2, 34 psi).
Cleaning Fuel Filter
When operation period reaches approx. 100 hours, clean the fuel filter.
This job should not be done in the field, but in a clean place so as to
prevent dust from entering fuel system. Close the fuel filter cock.
Unscrew and remove the screw ring, and remove the filter bowl, and rinse
the inside with kerosene. Take out the element and dip it in the
kerosene to rinse. After cleaning reassembling the fuel filter, keeping
out dust and dirt. Bleed the fuel system. If dust and dirt enter the
fuel, the fuel pump and injection nozzle are subject to wear. To prevent
this, be sure to clean the fuel filter bowl periodically.
Bleeding Fuel System
Air must removed: When the fuel filter or lines are removed. When tank
is completely empty. After the tractor has not been used for a long
period of time. Bleeding procedure is as follows: Fill the fuel tank
with fuel. Start the engine and run for about 30 seconds, and then stop
the engine.
Kubota B26, B2601, B2620, B2630 - Injection
Timing
Remove the injection pipes. Remove the engine stop solenoid. Turn the
flywheel counterclockwise (facing the flywheel) until fuel flows from
the delivery valve holder. Continue to turn the flywheel slowly, and
stop it as soon as the fuel level at the tip of the delivery valve
holder begins to increase. Check to see if the timing angle lines on the
flywheel is aligned with the alignment mark. If the injection timing is
out of adjustment, readjust the timing with shims. The sealant is
applied to both sides of the shim (soft metal gasket shim). The liquid
gasket is not required for assembling. Shims are available in thickness
of 0.20 mm (0.0079 in.), 0.25 mm (0.0098 in.), 0.30 mm (0.012 in.), 0.35
mm (0.014 in.) and 0.175 mm (0.00689 in.). Combine these shims for
adjustments. Addition or reduction of shim (0.025 mm, 0.00098 in.)
delays or advances the injection timing by approx. 0.0044 rad (0.25
degrees). In disassembling and replacing the injection pump, be sure to
use the same number of new shims with the same thickness. Injection
timing - 0.2662 to 0.3272 rad (17.25 to 18.75 degrees) before T.D.C.
Fuel Tightness of Pump Element
Remove the engine stop solenoid. Remove the injection pipes and glow
plugs. Install the injection pump pressure tester to the injection pump.
Install the injection nozzle jetted with the proper injection pressure
to the injection pump pressure tester. Set the speed control lever to
the maximum speed position. Operate the starter to increase the
pressure.
Fuel Tightness of Delivery Valve
Remove the engine stop solenoid. Remove the injection pipes and glow
plugs. Set a pressure tester to the fuel injection pump. Install the
injection nozzle jetted with the proper injection pressure to the
injection pump pressure tester. Operate the starter to increase the
pressure. Stop the starter when the fuel jets from the injection nozzle.
After that, turn the flywheel by the hand and raise the pressure to
approx. 13.73 MPa (140 kgf/cm2, 1991 psi). Now turn the flywheel back
about half a turn (to keep the plunger free). Keep the flywheel at this
position and clock the time taken for the pressure to drop from 13.73 to
12.75 MPa (from 140 to 130 kgf/cm2, from 1991 to 1849 psi). Measure the
time needed to decrease the pressure from 13.73 to 12.75 MPa (from 140
to 130 kgf/cm2, from 1991 to 1849 psi). If the measurement is less than
allowable limit, replace the pump with new one.
Nozzle Spraying Condition - Set the injection nozzle to a nozzle tester,
and check the nozzle spraying condition. If the spraying condition is
damaged, replace the nozzle piece. Nozzle Holder - Secure the nozzle
retaining nut with a vise. Remove the nozzle holder, and remove parts
inside. Assemble the nozzle in clean fuel oil. Install the push rod,
noting its direction. After assembling the nozzle, be sure to adjust the
fuel injection pressure.
Kubota B26, B2601, B2620, B2630 - Engine
Service
Top Clearance
Remove the cylinder head. Move the piston up and stick a strip of fuse
[1.5 mm dia. (0.059 in. dia.), 5.0 to 7.0 mm long (0.20 to 0.27 in.
long)] on the piston head at three positions with grease so as to avoid
the intake valve and the exhaust valve and the combustion chamber ports.
Lower the piston, and install the cylinder head and tighten the cylinder
head screws to the specified torque. Turn the flywheel until the piston
exceeds top dead center. Remove the cylinder head, and measure the
thickness of the squeezed fuses. If the measurement is not within the
factory specifications, check the oil clearance between the crankpin and
the crankpin bearing and between the piston pin and the small end
bushing.
Cylinder Head Surface Flatness and Flaw
Clean the cylinder head surface. Place a straightedge on the cylinder
head's four sides and two diagonal. Measure the clearance with a
thickness gauge. If the measurement exceeds the allowable limit, correct
it with a surface grinder. Top clearance - 0.55 to 0.75 mm / 0.022 to
0.029 in. Cylinder head screws - 64 to 68 Nm / 47 to 50 lbf-ft. Cylinder
Head Flaw - Prepare an air spray red check. Clean the surface of the
cylinder head with detergent. Spray the cylinder head surface with the
red permeative liquid. Leave it five to ten minutes after spraying. Wash
away the read permeative liquid on the cylinder head surface with the
detergent. Spray the cylinder head surface with white developer. If
flawed, it can be identified as red marks.
Valve Recessing
Clean the cylinder head surface, the valve face and the valve seat.
Insert the valve into the valve guide. Measure the valve recessing with
a depth gauge. If the measurement exceeds the allowable limit, replace
the valve. If it still exceeds the allowable limit after replacing the
valve, replace the cylinder head. Clearance between Valve Stem and Valve
Guide - Remove carbon from the valve guide section. Measure the valve
stem O.D. with an outside micrometer. Measure the valve guide I.D. with
a small hole gauge, and calculate the clearance. If the clearance
exceeds the allowable limit, replace the valves. If it still exceeds the
allowable limit, replace the valve guide. Valve recessing - 0.050
(protrusion) to 0.25 (recessing) mm / 0.0020 (protrusion) to 0.0098
(recessing) in. Clearance between valve stem and valve guide - 0.035 to
0.065 mm / 0.0014 to 0.0025 in. Valve stem O.D - 6.960 to 6.975 mm /
0.2741 to 0.2746 in. Valve guide I.D - 7.010 to 7.025 mm / 0.2760 to
0.2765 in.
Kubota B26, B2601, B2620, B2630 - Replacing
Valve Guide
Press out the used valve guide using a valve guide replacing tool. Clean
a new valve guide and valve guide bore, and apply engine oil to them.
Press in a new valve guide using a valve guide replacing tool. Ream
precisely the I.D. of the valve guide to the specified dimension. Valve
Seating - Coat the valve face lightly with prussian blue and put the
valve on its seat to check the contact. If the valve does not seat all
the way around the valve seat or the valve contact is less than 70 %,
correct the valve seating as follows. If the valve contact does not
comply with the reference value, replace the valve or correct the
contact of valve seating. Valve guide I.D (Intake and exhaust) - 7.010
to 7.025 mm / 0.2760 to 0.2765 in. Valve seat width - 2.12 mm / 0.0835
in.
Correcting Valve and Valve Seat
Before correcting the valve and the seat, check the valve stem and the
I.D. of valve guide section, and repair them if necessary. After
correcting the valve seat, be sure to check the valve recessing. Correct
the valve with a valve refacer. Slightly correct the seat surface with a
0.79 rad (45 degrees) / 1.0 rad (60 degrees) valve seat cutter. Fitting
the valve, check the contact position of the valve face and seat surface
with prussian blue. Visual check - If the valve has been used for a long
period, the seat tends to come in contact with the upper side of the
valve face. Grind the upper surface of the seat with a 0.52 rad (30
degrees) valve seat cutter until the valve seat touches to the center of
the valve face. Grind the seat with a 0.26 rad (15 degrees) valve seat
cutter again, and visually recheck the contact between the valve and the
seat. Repeat steps 3 and 4 until the correct contact is achieved.
Continue lapping until the seated rate becomes more than 70 % of the
total contact area.
Valve Lapping
Apply compound evenly to the valve lapping surface. Insert the valve
into the valve guide. Lap the valve onto its seat with a valve flapper
or screwdriver. After lapping the valve, wash the compound away and
apply oil, then repeat valve lapping with oil. Apply prussian blue to
the contact surface to check the seated rate. If it is less than 70 %,
repeat valve lapping again. When valve lapping is performed, be sure to
check the valve recessing and adjust the valve clearance after
assembling the valve. Valve face angle: IN. 1.0 rad / 60 degrees, EX.
0.79 rad / 45 degrees. Valve seat angle: IN. 1.0 rad / 60 degrees, EX.
0.79 rad / 45 degrees.
Free Length and Tilt of Valve Spring
Measure the free length of valve spring with vernier calipers. If the
measurement is less than the allowable limit, replace it. Put the valve
spring on a surface plate, place a square on the side of the valve
spring. Check to see if the entire side is in contact with the square.
Rotate the valve spring and measure the maximum tilt. If the measurement
exceeds the allowable limit, replace it. Check the entire surface of the
valve spring for scratches. If there is any problem, replace it. Valve
Spring Setting Load - Place the valve spring on a tester and compress it
to the same length it is actually compressed in the engine. Read the
compression load on the gauge. If the measurement is less than the
allowable limit, replace it.
Oil Clearance between Rocker Arm and Rocker
Arm Shaft
Measure the rocker arm shaft O.D. with an outside micrometer. Measure
the rocker arm I.D. with an inside micrometer, and then calculate the
oil clearance. If the oil clearance exceeds the allowable limit, replace
the rocker arm and measure the oil clearance again. If it still exceeds
the allowable limit, replace also the rocker arm shaft. Tilt Allowable
limit - 1.0 mm / 0.039 in. Free length - 37.0 to 37.5 mm / 1.46 to 1.47
in. Oil clearance between rocker arm and rocker arm shaft - 0.016 to
0.045 mm / 0.00063 to 0.0017 in. Rocker arm shaft O.D - 11.973 to 11.984
mm / 0.47138 to 0.47181 in. Rocker arm I.D - 12.000 to 12.018 mm /
0.47244 to 0.47314 in. Push Rod Alignment - Place the push rod on V
blocks. Measure the push rod alignment. If the measurement exceeds the
allowable limit, replace the push rod. Oil Clearance between Tappet and
Tappet Guide Bore - Measure the tappet O.D. with an outside micrometer.
Measure the I.D. of the tappet guide bore with a cylinder gauge, and
calculate the oil clearance. If the oil clearance exceeds the allowable
limit or the tappet is damaged, replace the tappet.
Kubota B26, B2601, B2620, B2630 - Idle Gear
Timing Gear Backlash - Set a dial indicator (lever type) with its tip on
the gear tooth. Move the gear to measure the backlash, holding its
mating gear. If the backlash exceeds the allowable limit, check the oil
clearance of the shafts and the gear. If the oil clearance is proper,
replace the gear. Push rod alignment Allowable limit - 0.25 mm / 0.0098
in. Oil Clearance between tappet and tappet guide bore - 0.020 to 0.062
mm / 0.00079 to 0.0024 in. Tappet O.D - 19.959 to 19.980 mm / 0.78579 to
0.78661 in. Tappet guide bore I.D - 20.000 to 20.021 mm / 0.78740 to
0.78822 in. Backlash between idle gear 1 and crank gear - 0.0320 to
0.115 mm / 0.00126 to 0.00452 in. Backlash between idle gear 1 and cam
gear - 0.0360 to 0.114 mm / 0.00142 to 0.00448 in. Backlash between idle
gear 1 and injection pump gear - 0.0340 to 0.116 mm / 0.00134 to 0.00456
in. Idle gear 1 and idle gear 2 - 0.0330 to 0.117 mm / 0.00130 to
0.00460 in. Idle Gear 1 and 2 Side Clearance - Set a dial indicator with
its tip on the idle gear. Measure the side clearance by moving the idle
gear to the front and rear. If the measurement exceeds the allowable
limit, replace the idle gear collar.
Camshaft
Camshaft Side Clearance - Set a dial indicator with its tip on the
camshaft. Measure the side clearance by moving the cam gear to the front
to rear. If the measurement exceeds the allowable limit, replace the
camshaft stopper. Camshaft Alignment - Support the camshaft with V
blocks on the surface plate at both end journals. Set a dial indicator
with its tip on the intermediate journal. Measure the camshaft
alignment. If the measurement exceeds the allowable limit, replace the
camshaft. Cam Height - Measure the height of the cam at its highest
point with an outside micrometer. If the measurement is less than the
allowable limit, replace the camshaft. Idle gear 1 and 2 side clearance
- 0.20 to 0.51 mm / 0.0079 to 0.020 in. Camshaft side clearance - 0.070
to 0.22 mm / 0.0028 to 0.0086 in. Camshaft alignment Allowable limit -
0.01 mm / 0.0004 in. Cam height of intake - 28.80 mm / 1.134 in. Cam
height of exhaust - 29.00 mm / 1.142 in. Oil Clearance of Camshaft
Journal - Measure the camshaft journal O.D. with an outside micrometer.
Measure the cylinder block bore I.D. for camshaft with a cylinder gauge,
and calculate the oil clearance. If the oil clearance exceeds the
allowable limit, replace the camshaft.
Piston and Connecting Rod
Piston Pin Bore I.D - Measure the piston pin bore I.D. in both the
horizontal and vertical directions with a cylinder gauge. If the
measurement exceeds the allowable limit, replace the piston. Oil
clearance of camshaft journal - 0.050 to 0.091 mm / 0.0020 to 0.0035 in.
Camshaft journal O.D - 35.934 to 35.950 mm / 1.4147 to 1.4153 in.
Camshaft bearing I.D (Cylinder block bore I.D.) - 36.000 to 36.025 mm /
1.4173 to 1.4183 in. Piston pin bore I.D - 22.000 to 22.013 mm / 0.86615
to 0.86665 in. Oil Clearance between Piston Pin and Small End Bushing -
Measure the piston pin O.D. where it contacts the bushing with an
outside micrometer. Measure the small end bushing I.D. with an inside
micrometer, and calculate the oil clearance. If the oil clearance
exceeds the allowable limit, replace the bushing. If it still exceeds
the allowable limit, replace the piston pin. Clean a new small end
bushing and bore, and apply engine oil to them. Using a small end
bushing replacing tool, press in a new bushing (service parts) taking
care to see that the connecting rod oil hole matches the bushing hole.
Oil clearance between piston pin and small end bushing - 0.014 to 0.038
mm / 0.00055 to 0.0014 in. Piston pin O.D - 22.002 to 22.011 mm /
0.86622 to 0.86657 in. Small end bushing I.D - 22.025 to 22.040 mm /
0.86713 to 0.86771 in. Oil clearance between piston pin and small end
bushing (Spare parts) - 0.014 to 0.038 mm / 0.00056 to 0.0014 in. Small
end bushing I.D (Spare parts) - 22.025 to 22.040 mm / 0.86713 to 0.86771
in.
Kubota B26, B2601, B2620, B2630 - Piston Rings
Piston Ring Gap - Insert the piston ring into the lower part of the
cylinder (the least worn out part) with a piston. Measure the ring gap
with a thickness gauge. If the measurement exceeds the allowable limit,
replace the piston ring. Clearance between Piston ring and Piston Ring
Groove - Clean the rings and the ring grooves, and install each ring in
its groove. Measure the clearance between the ring and the groove with a
feeler gauge or depth gauge. If the clearance exceeds the allowable
limit, replace the piston ring. If the clearance still exceeds the
allowable limit with new ring, replace the piston. Piston ring gap: Top
ring - 0.15 to 0.25 mm / 0.0059 to 0.0098 in. Second ring - 0.40 to 0.55
mm / 0.016 to 0.021 in. Oil ring - 0.25 to 0.45 mm / 0.0091 to 0.017 in.
Clearance between piston ring and piston ring groove: Second ring -
0.0950 to 0.122 mm / 0.00374 to 0.00480 in. Oil ring - 0.020 to 0.060 mm
/ 0.00079 to 0.0023 in.
Connecting Rod Alignment
Remove the crankpin bearing, and install the connecting rod cap. Install
the piston pin in the connecting rod. Install the connecting rod on the
connecting rod alignment tool. Put a gauge over the piston pin, and move
it against the face plate. If the gauge does not fit squarely against
the face plate, measure the space between the pin of the gauge and the
face plate. If the measurement exceeds the allowable limit, replace the
connecting rod.
Crankshaft
Crankshaft Side Clearance - Set a dial indicator with its tip on the end
of the crankshaft. Measure the side clearance by moving the crankshaft
to the front and rear. If the measurement exceeds the allowable limit,
replace the thrust bearings. If the same size bearing is useless because
of the crankshaft journal wear, replace it with an oversize one
referring to the table. Crankshaft Alignment - Support the crankshaft
with V blocks on the surface plate at both end journals. Set a dial
indicator with its tip on the intermediate journal. Measure the
crankshaft alignment. If the measurement exceeds the allowable limit,
replace the crankshaft. Space between gauge pin face plate - Allowable
limit 0.05 mm / 0.002 in. Crankshaft side clearance - 0.15 to 0.31 mm /
0.0059 to 0.012 in. Oversize 0.20 mm / 0.0079 in. The crankshaft journal
must be fine-finished to higher than Rmax = 0.8S. Crankshaft alignment -
Allowable limit 0.02 mm / 0.0008 in. Oil Clearance between Crankpin and
Crankpin Bearing - Clean the crankpin and crankpin bearing. Put a strip
of plastigauge on the center of the crankpin. Install the connecting rod
cap and tighten the connecting rod screws to the specified torque, and
remove the cap again. Measure the amount of the flattening with the
scale, and get the oil clearance. If the oil clearance exceeds the
allowable limit, replace the crankpin bearing.
Cylinder
Cylinder Wear - Measure the I.D. of the cylinder at the six positions
with a cylinder gauge to find the maximum and minimum I.D.'s. Get the
difference (Maximum wear) between the maximum and the minimum I.D.'s. If
the wear exceeds the allowable limit, bore and hone to the oversize
dimension. Visually check the cylinder wall for scratches. If deep
scratches are found, the cylinder should be bored. Correcting Cylinder -
When the cylinder is worn beyond the allowable limit, bore and hone it
to the specified dimension. Replace the piston and piston rings with
oversize ones. Oversize: 0.5 mm (0.02 in.). When the oversize cylinder
is worn beyond the allowable limit, replace the cylinder block with a
new one.
________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________