ENGINE LOCATION INDEX … … … … … … … … … … … … … … … … … … …………A-3 MECHANICAL LOCATION INDEX … … … … … … … … … … … … ……A-3 ENGINE TIMING… … … … … … … … … … … … … … … … … …… …… ……A-4 TOP AND BOTTOM TIMING GEAR COVER ASSEMBLY …… … …… ……A-4 TIMING BELT REMOVAL …… … …… … …… … …… … …… … …… …A-4 TIMING BELT INSTALLATION AND ALIGNMENT … …… … …… … ……A-5 DRIVER BELT, TENSION PULLEY AND GENERATOR … …… … …… … …A-7 DETERMINATION OF ENGINE TIMING（TDC FOR CYLINDER 1）… …… …A-7 VALVE CLEARANCE … …… … …… … …… … …… … …… …
FLY WHEEL REMOVAL AND INSTALLATION … … … … … … … … ……A-23 REAR OIL SEAL REPLACEMENT … …… … …… … …… … …… … …… A-23 CAMSHAFT … … …… … …… … …… … …… … …… … …… … …… … …… A-25 CAMSHAFT GEAR … …… … …… … …… … …… … …… … …… … … …A-25 CAMSHAFT AND CAMSHAFT THRUST SPACER … …… … …… … …… …A-25 SIZE OF CAMSHAFT JOURNAL AND HOLE OF THE CYLINDER HEAD … A-27 CRANKSHAFT … … …… … …… … …… … …… … …… … …… … …… … …A-28 CRANKSHAFT, CRANKSHAFT THRUST SPACER， BEARING SHELL AND MAIN BEARING CAP … … … … … … …… … … …A-28 PISTON AND CONN
LOCATION INDEX MECHANICAL LOCATION INDEX 1 2 3 4 5 6 7 8 TIMING BELT (SEE A-4 ENGINE TIMING) VALVE MECHANISM COMPONENTS (SEE A-9 VALVE CLEARANCE) CYLINDER HEAD GASKET (SEE A-19 CYLINDER HEAD GASKET REPLACEMENT) FRONT OIL SEAL (SEE A-21 FRONT OIL SEAL REPLACEMENT) REAR OIL SEAL (SEE A-23 REAR OIL SEAL REPLACEMENT) CAMSHAFT (SEE A-25 CAMSHAFT) CRANKSHAFT (SEE A-28 CRANKSHAFT, CRANKSHAFT THRUST SPACER, BEARING SHELL AND MAIN BEARING CAP) PISTON AND CONNECTING ROD (SEE A-33 PISTON AND CONNECTING ROD ASSEMBL
ENGINE TIMING TOP AND BOTTOM TIMING GEAR COVER ASSEMBLY Removal Loosen and unscrew two bolts of the top timing gear cover assembly. Remove the top timing gear cover and gasket assembly. Remove the gasket from the top timing gear cover. Remove the crank pulley. Loosen and unscrew the two bolts on the timing gear cover. Remove the timing gear cover and gasket assembly. Remove the gasket from the bottom timing gear cover.
Note: After the belt is taken out, do not rotate the gear to a large extent, otherwise the piston head and the valve will be damaged due to collision. To continue using the removed belt, carefully check whether there is abnormal abrasion, stratified cracks (especially those around the root) or fouling on the belt. Replace it immediately even if the slightest suspicion exists. TIMING BELT INSTALLATION AND ALIGNMENT Check whether the crank shaft is in the TDC position for the first cylinder.
Hold the middle of the right belt that is away from both the crankshaft gear and camshaft gear with the thumb and the first finger. If the tension of the belt is up to standard, the belt shall be able to twist at 90°at this point. To adjust the tension of the belt, loosen the two fixing bolts of the tension pulley, push the tension pulley to the right with a screwdriver as a ram, then fasten the fixing bolts again, rotate the crank shaft and check the tension again.
DRIVER BELT, TENSION PULLEY AND GENERATOR Removal Pull the abutment on the tension pulley by tools to the direction of the generator (or align the gauge holes on the front and rear part of the tensioning device and drive a pin to fix the tensioning device). Remove the driver belt and the two fixing bolts on the generator to take the generator out. For installation, reverse the above removal steps.
Check whether the TDC indicator on the cam shaft gear lines up with that on the front end of cylinder head. If not, rotate the crank shaft clockwise in one full circle to make them line up with each other. At this time, the engine is in the position of TDC of the first cylinder. In case the crank pulley and timing gear have been removed, the TDC for the first cylinder can be determined as follows: Rotate the crankshaft to make the TDC indicator on the crank pulley line up with that on the oil pump body.
VALVE CLEARANCE VALVE MECHANISM COMPONENTS Rocker arm (8 pcs) Rocker nut (16 pcs) Tightening torque: 25~29Nm Rocker ram seat (8 pcs) Valve keeper (16 pcs) Upper seat of valve spring (8 pcs) Rocker ram seat washer (8 pcs) Hydraulic tappet (8 pcs) Clearance: 0.023~0.065 Valve spring (8 pcs) Lower seat of valve spring (8 pcs) Rocker arm stud (8 pcs) Torque: 18~23Nm Exhaust valve (4 pcs) (LH) Clearance: 0.046~0.095 Intake valve (4pcs) (RH) Clearance: 0.02~0.
Cupped gasket VALVE COVER AND GASKET Removal Gasket assembly for valve cover Remove 9 bolts to take out the cupped gasket and high tension wire support, clutch and throttle cable support. Remove the valve cover and gasket assembly. Take the sheet gasket out. Installation Clean the junction face of the cylinder head and the valve cover. Push the wedge of the sheet gasket for the valve cover into corresponding valve cover to integrate them.
ROCKER MECHANISM Removal Loosen the rocker nuts to take them out. Take the level bracket out. Take the rocker arm out. Take the gasket of the level bracket out. Place each set of rock arm and level bracket in one same plastic bag for distinction. The removed rocker nuts cannot be reused. Installation: Check whether theire is abnormal abrasion on the contact surface of the rocker. Replace it if necessary. Put the rocker seat gasket into the stud. Lubricate the rocker arm and rocker seat by motor oil.
HYDRAULIC TAPPET Removal Take the hydraulic tappets out and place them into an oil-filled vessel to prevent the hydraulic tappet oil from leaking out. Check the top and bottom contact surfaces of the hydraulic tappet to observe whether there are abnormal abrasion or scrapes. If yes, replace it with new one if necessary. Installation Apply hyperbolic gear oil or motor oil on the tappet and external diameter as well as its two ends and place the tappet into the cylinder head hole in the original order.
VALVE, VALVE SPRING AND OIL SEAL ASSEMBLY OF THE VALVE Removal Compress the valve spring with a special compression device and take the valve cotter out. Do not over compress the spring, which shall be compressed to the travel stroke that the valve cotter can slide from the groove, otherwise the valve stem may bend. If the valve cotter cannot slide out when the spring is compressed, remove the compression device and place a proper pipe on the spring seat. In this way, the valve cotter will not be collided.
Valve stem size and fit clearance Intake（mm） Class Inner Diameter of Diameter of valve stem valve guide 8.043 +−00.018 8.063—8.094 Oversized 8.443 +−00.018 0.4 8.463—8.494 Standard Exhaust（mm） Clearance 0.02— 0.069 Diameter of valve stem Inner Diameter Clearance of valve guide 8.017 +−00.018 8.063—8.094 8.417 +−00.018 8.463—8.494 Measure the free length and elasticity of the valve spring Compression length (mm) Spring load (N) L1=37.084 422 L2=27.7 892.7 L3=27.
Grinding valve and valve seat ring UAES’s new two-valve Face angle of intake valve Width of the sealing band for the intake valve seat ring Face angle of exhaust valve Width of the sealing band for the exhaust valve seat ring 44º30′---45º30′ 1.75---2.32mm 91º (0º-0º30ˊ) 1.44±0.1 Installation Before installation, the cylinder head shall be completely cleaned and there shall be no any trace of abrasive dust on the cylinder head, valve or valve guide.
Size of intake valve seat ring and cylinder head seat ring bore Class Diameter of intake valve seat ring (unit: mm) Diameter of the seat ring bore of cylinder head (mm) Standard 43.877 +−00..01 01 43.763 0+0.025 Oversized 0.5 Oversized 1.0 44.377 +−00..01 01 44.263 0+0.025 44.877 +−00..01 01 44.763 0+0.025 Interfer ence (mm) 0.079 — 0.
COMPRESSION PRESSURE COMPRESSION INSPECTION Warning ·Hot engines and oil can cause severe burns. Be careful not to burn yourself during removal/installation of each component. 1. Verify that the battery is fully charged. ·Recharge it if necessary. 2. Warm up the engine to the normal operating temperature. 3. Stop the engine and allow it to cool off for about 10 min. 4. Perform “Fuel Line Safety Procedures”. Leave the fuel pump relay removed. Warning ·Fuel vapor is hazardous.
Cylinder Pressure Standard Value：1.00-1.35 Mpa (10-13.5 kgf/cm2) 11. Disconnect the compression gauge. 12. Install the spark plugs. 13. Connect the ignition coil connector. 14. Install the fuel pump relay. A-18 PDF created with pdfFactory Pro trial version www.pdffactory.
CYLINDER HEAD GASKET CYLINDER HEAD GASKET REPLACEMENT Removal Rotate the cam shaft clockwise until the key slot goes downwards vertically. Loosen the bolts on the cylinder head in the order illustrated in the figure. Note: The bolts removed from the cylinder head must be changed and cannot be reused. Inspection and Installation Check the out-of-flat of the base plane of the cylinder head, which shall not be above 0.15mm. Clean the threaded holes of the cylinder block.
Put the cylinder gasket into the dowel. Note: The side with indicator of the cylinder gasket shall be upward. Install the cylinder head in place with the key slot of the cam shaft downward vertically. Note: The cylinder gasket can only be used for one time, so the removed one shall be replaced with a new one when removing the cylinder head. A. Location Pin Put the bolts and the flat gasket of the cylinder head into the threaded hole to screw them in by hands.
FRONT OIL SEAL CRANKSHAFT PULLEY Removal Removal 3 fixing bolts on the starter to take it out. Fasten the flywheel ring gear with a proper screwdriver or rod to disenable the crank shaft to rotate. Loosen the fixing bolts of the crank pulley and take out the bolts and washer to pull out the pulley (use a gear puller, if necessary). Installation Clean the pulley and crankshaft journals and wipe clean the lube in the pulley groove.
CRANKSHAFT GEAR Removal Fix the crankshaft to disenable it to rotate and remove the pulley. Pull the crankshaft gear out by a wheel puller or two large-size screw drivers and remove the whiney key. Installation Check whether there are abrasion, pit corrosion or scrapes on the gear. Install the whiney key, with a protrusion height of 1.392-1.739mm. Install the gasket and pay attention to its direction (with the warped surface forward).
REAR OIL SEAL FLY WHEEL REMOVAL AND INSTALLATION Removal Remove 9 fixing bolts. New bolts shall be used for installation. Remove the fly wheel to check whether there are cracks on the friction surface of the clutch plate and there is abrasion and pit corrosion on the teeth of the ring gear, etc. Installation The clearance of the ring gear and the fly wheel is 0.48-0.86mm. The ring gear shall be pressed into the fly wheel after heating.
Pries the rear oil seal out of the rear oil seal support with a chisel or a screwdriver. Note: do not damage the rear oil seal support. Installation Put the support on the vice clamp whose jaw has a piece of wood. Make the side with the part numbers of the rear oil seal outward and align the rear oil seal with the rear oil seal support bore. Press the rear oil seal into its support with a vice clamp, with the clearance between the rear oil seal and oil seal support bore to be 0.26—0.50mm.
CAMSHAFT CAMSHAFT GEAR Removal Rotate the crankshaft to the compression TDC position of the first cylinder. Remove the belt. Put one pole into one hole of the cam shaft gear to lock it. Loosen the gear bolts and remove them and the gasket. Note: New bolts shall be used for reinstallation. The camshafts of different engines are not interchangeable. In case the cam shaft shall be replaced, replace it with a new one according to the indicators on the original gear.
Draw the cam shaft assembly out from the rear end of the cylinder head and be careful not to damage the cam shaft hole of the cylinder head during this process. Inspection Check whether there is any abrasion on the cam and the journal of the cam shaft. Change the one with serious abrasion. Change the thrust space if the axial clearance of the cam shaft is above the specification.
SIZE OF CAMSHAFT JOURNAL AND HOLE OF THE CYLINDER HEAD Installation To replace the cam shaft, observe the shape of the rear end of the cam shaft for right selection. Before installation, apply the cam of the cam shaft with hyperbolic gear oil or motor oil. The cam shaft shall be assembled from the cylinder head in a back-to-front order. Apply some motor oil to the thrust spacer of the cam shaft and put the thrust spacer into the groove of the cylinder head.
CRANKSHAFT CRANKSHAFT, CRANKSHAFT THRUST SPACER, BEARING SHELL AND MAIN BEARING CAP Removal Check the axial clearance of the crank shaft before removal. Kiss the end side of the crank shaft with the contacts of a dial gauge (less degree of shrinkage). Push the crank shaft away from the contacts and adjust the dial gauge to 0, then push the crank shaft to the direction of contacts as possible with a0 stout carrying pole. Check the reading of the dial gauge, which shall be the axial clearance.
Install the main bearing cap. Tighten the bolts of the main bearing cap at the moment of 90-100N.m by hands. Do not rotate the crank shaft. Remove the main bearing bolts. Carefully take out the main bearing cap and arrange them in order. Read the bearing clearance according to the ratio on the envelope of the plastic clearance gauge. Check the bearing clearance from the third main bearing and extend to both sides. The main bearing clearance shall be 0.011—0.058mm.
Diameter of main journal and size of main bearing shell Class Standard Oversized by 0.4 Downsized by 0.02 Downsized by 0.25 Downsized by 0.50 Downsized by 0.75 Downsized by 0.25 and oversized by 0.4 Downsized by 0.50 and oversized by 0.4 Downsized by 0.75 and oversized by 0.4 57.98—58.00 57.98—58.00 57.98—58.00 57.73—57.75 57.48—57.50 57.23—57.25 Diameter of the main bearing bore of the cylinder block (unit: mm) 62.2935+0.0065 62.6935+0.0065 62.2935+0.0065 62.2935+0.0065 62.2935+0.0065 62.2935+0.
Installation Before installation, tap the threaded hole on the cylinder block with tapping drill, especially those of the cylinder head bolts and main bearing bolts. Cylinder head bolt: M10X1.5~6H Main bearing bolt: M12X1.75~6H Installation of the whiney key of the crank shaft: gently drive the whiney key into the key slot. The clearance between the whiney key and key slot is 0.00~0.051mm. Check the protrusion after the whiney key is installed, which shall be 1.392~1.739mm.
shall be installed on the left threaded hole of the fourth main bearing cap (seeing from the front). Apply some motor oil on the head joint before installing the main bearing cap bolts. Tighten the main bearing cap bolts and stud by hands, then tighten them to the moment of 90~100Nm. The twist moment of the crank shaft (assembly with piston connecting rod) is 16Nm max.
PISTON AND CONNECTING ROD ASSEMBLY PISTON REMOVAL, MEASURE AND INSTALLATION Removal Rotate the crank shaft to the bottom dead center (BDC) of the removed cylinder, check whether there is a cylinder number on the connecting rod body and cap, which shall be on the left of the rod (seeing from the front). If there is no such a number, number each cylinder before removal.
Rinsing and inspection Rinse and clean the carbon deposit on the piston, piston ring and pin. Rinse and clean the carbon deposit on the bottom of the cylinder bore. Measure the diameter of the cylinder bore. Ex-factory grouping Ex-factory repair For Maintenance 480 M cylinder bore (unit: mm) 1 79.94-79.95 2 79.95-79.96 3 79.96-79.97 4 79.97-79.98 A 80.23-80.24 B 80.24-80.25 C 80.25-80.26 Standard 79.965-77.975 Oversized by 0.29 80.245-80.255 0.29by 0.5 Oversized 80.466-80.
Diameter of 480M piston skirt (unit: mm) 1 2 3 4 A Ex-factory B repair C Standard Spare Oversized by 0.29 parts Oversized by 0.5 Ex-factory grouping 79.91-79.92 79.92-79.93 79.93-79.94 79.94-79.95 80.20-80.21 80.21-80.22 80.22-80.23 79.93-79.955 80.21-80.235 80.43-80.455 Diameter of 480E piston skirt (unit: mm) 79.915-79.925 79.925-79.935 79.935-79.94 79.945-79.955 80.205-80.215 80.215-80.225 80.225-80.235 79.965-79.975 80.245-80.255 80.465-80.
Measure the axial clearance of piston ring in the piston groove Height of the piston ring (unit: mm) 1.60 0-0.012 First compression ring Second compression ring 2.0 Sealing strip of oil ring Spring of oil ring 0.61±0.025 0 -0.012 2.68±0.05 4.0 -0.015 Cast iron oil ring Size of piston ring groove (unit: mm) 1.6 +0.06 +0.04 2.0 +0.06 +0.04 4.0 +0.03 +0.01 4.0 -0.025 +0.03 +0.01 Fit clearance (unit: mm) 0.050-0.082 0.050-0.082 0.01-0.23 0.025-0.
Installation Piston weights and spare piston skirts are not grouped, but the piston pin holes shall be grouped. Before assembly, check the piston crown marks. The marks of the four cylinders must be same. Heat the small end of the connecting rod to 230~400℃, apply SAE50 lube or glue type of graphite oil, then press the piston pin into the small end bore of the connecting rod and the piston pin bore. One end of the piston pin can be 0.
Size of piston ring 480# piston ring Paint mark (type) Paint mark (type) No paint (Standard) No paint (Standard) Purple paint (oversized by 0.29) Purple paint (oversized by 0.29) Blue paint (oversized by 0.5) Blue paint (oversized by 0.
