SECTION T MAZDA MX-5 1994 Workshop Manual

FUNDAMENTAL PROCEDURES 1. Inspection of parts When removed, each part should be carefully inspected for malfunctioning, deformation, damage, and other problems. 2. Arrangement of parts All disassembled parts should be carefully arranged for reassembly.Be sure to separate or otherwise identify the parts to be replaced from those that will be reused. 3. Cleaning parts for reuse All parts to be reused should be carefully and thoroughly cleaned in the appropriate method. Warning Using compressed air can cause dirt and other ,, particles to fly out, causing injury to the eyes. Wear protective eye wear whenever using com- pressed air. REASSEMBLY Standard values, such as torques and certain adjust- ments, must be strictly observed in the reassembly of all parts. Refer to STANDARD BOLT AND NUT TIGHTENING TORQUE in section TD for tightening torques not men- tioned in the main text. If removed, these parts should be replaced with new ones: 1. Oil seals 4. Gaskets 2. O-rings 5. Lock washers 3. Cotter pins 6. Nylon nuts Depending on location: 1. Sealant should be applied to gaskets. 2. Oil should be applied to the moving components of parts. 3. Specified oil or grease should be applied at the pre- scribed locations (such as oil seals) before reassembly. Gartner Banana

G I ELECTRICAL TROUBLESHOOTING TOOLSIELECTRICAL PARTS I VOLTMETER I BLACK LINE GROUND ELECTRICAL TROUBLESHOOTING TOOLS TEST LIGHT 4) The test light, as shown in the figure, uses a 12V bulb. The two lead wires should be connected to probes.The test light is used for simple voltage checks and for check- ing for short circuits. Caution Using a bulb over 3.4W when checking the control unit may damage the control unit. JUMPER WIRE A jumper wire is used to create a temporary circuit. Con- nect the jumper wire between the terminals of a circuit to bypass a switch. Caution Do not connect a jumper wire from the power source line to a body ground; this may cause burning or other damage to harnesses or elec- tronic components. VOLTMETER The DC voltmeter is used to measure circuit voltage. A voltmeter with a range of 15V or more is used by con- necting the positive (+) probe (red lead wire) to the point where voltage is to be measured and the negative (-) probe (black lead wire) to a body ground. d OHMMETER The ohmmeter is used to measure the resistance between two points in a circuit, and to check for continu- ity and short circuits. I I 45UGIX-006 GI-I 4 Caution Do not connect the ohmmeter to any circuit to which voltage is applied; this will damage the ohmmeter. ELECTRICAL PARTS BAlTERY The battery installed in the right rear of the trunk is unique. When a replacement battery is installed, install it with a genuine Mazda battery replacement kit or equivalent. (Refer to section G.) J Gartner Banana

G I INSTALLATION OF MOBILE TWO-WAY RADIO SYSTEMIAUDIO ANTITHEFT SYSTEM INSTALLATION OF MOBILE TWO-WAY RADIO SYSTEM If a mobile two-way radio system is installed improperly or if a high-powered type is used, the CIS and other systems may be affected. L-.) When the vehicle is to be equipped with a mobile two-way radio, observe the following precautions: 1. lnstall the antenna at the farthest point from control units. 2. Install the antenna feeder as far as possible from the control unit harnesses (at least 30 cm (11.8 in)). 3. Ensure that the antenna and feeder are properly adjusted. 4. Do not install a hiah-h owe red mobile two-wav radio svstem. FEEDER W!RE CONTROL UNIT HARNESS AT LEAST 30 cm (11.8 in) 46UGIX-043 AUDIO ANTITHEFT SYSTEM An audio with an antitheft function is optionally available. Before removing the negative battery terminal or discon- necting the audio power source, obtain the code number and deactivate the audio antitheft system. (Refer to section T.) Gartner Banana

PRE-DELIVERY INSPECTION PRE-DELIVERY INSPECTION PRE-DELIVERY INSPECTION TABLE The following items may be done at any time prior to delivery to your customer. INSPECT and ADJUST, if necessary, the following items to specification: 0 Glass, exterior bright metal and paint for damage 0 Convertible top and detachable hardtop (if equipped) for damage 0 Wheel lug nuts and locks 89-117 N.m (9-1 2 kgf.m, 66-86 ft4bf) 0 All weatherstrips for damage or detachment Operation of hood release and lock Operation of fuel lid 0 Door operation and alignment Headlight aiming INSTALL the following parts: Wheel caps (if equipped) 0 Outside mirror(s) 0 Mast antenna (if equipped) UNDER HOOD-ENGINE OFF INSPECT and ADJUST, if necessary, the following items to specification : Fuel, coolant, and hydraulic lines, fittings, connections, and components for leaks Engine oil level 0 Power steering fluid level (if equipped) Brake and clutch master cylinder fluid level 0 Windshield washer reservoir fluid level 0 Radiator coolant level and specific gravity 0 Tightness of battery terminals pKiq INSTALL the following parts: CHECK operation of the following items: 0 Seat controls (sliding and reclining) 0 Door locks 0 Seat belts and warning system 0 Air bag system using indicator light (Refer to section T) Ignition switch and steering lock 0 Starter interlock switch (clutch pedal) All lights, including warning, and indicator lights 0 Audible warning system 0 Horn, wipers, and washers Audio system 0 Cigarette lighter Power windows (if equipped) 0 Power outside mirrors (if equipped) 0 Heater, defroster, and air conditioner at all mode selections (if equipped) CHECK the following items: Presence of spare fuses 0 Upholstery and interior finish CHECK and ADJUST, if necessary, the following items: 0 Pedal height and free play of brake and clutch pedals I Pedal height mm {in} I Ft: $iy I Clutch pedal {6.89--7.28) (with carpet) Parking brake 7-9 notchesil96 N (20 kgf, 44 Ibf) 0.63.1 (0.024. 12) Brake pedal RUNNING AT OPERATING TEMPERATURE CHECK the following items: 0 Automatic transmission oil level 171-181 (6.73--7.13) (with carpet) I ON HOIST I 4--7 {0.16-0.28} CHECK the following items: 0 Underside fuel, coolant, and hydraulic lines, fittings, con- nections, and components for leaks 4 Tires for cuts or bruises 0 Steering linkage, suspension, exhaust system, and all underside hardware for looseness or damage Manual transmission oil level Differential oil level I ROAD TEST I CHECK the following items: Brake operation Clutch operation 0 Steering control 0 Operation of meters and gauges Squeaks, rattles and unusual noises 0 Overall engine performance Seat belt emergency locking retractors 0 Cruise control system (if equipped) I AFTER ROAD TEST I CHECK for necessary owner information materials, tools and spare tire in vehicle The following items must be done just before the delivery to your customer. 0 Load test battery and charge if necessary -1 Install fuses for accessories Adjust tire pressure to specification Load test fesuk 0 Remove seat and floor mat protective covers (Refer to Door Label) 0 Vacuum and clean interior of vehicle Clean outside of vehicle Inspect installation of option parts with invoice 45UOAX-002 Gartner Banana

Before beginning any service procedure. refer to section T of this manual for air bag system service warnings and audio antitheft system alarm conditions . ENGINE INDEX ............................. B- 2 OUTLINE .......................... B- 3 SPECIFICATIONS ................ B- 3 TROUBLESHOOTING GUIDE ........ B- 3 ENGINE TUNE-UP .................. 8- 5 PREPARATION ................... B- 5 ENGINE OIL ..................... B- 5 ENGINE COOLANT ............... B- 5 DRIVE BELT ..................... 8- 6 HLA TROUBLESHOOTING GUIDE . 8- 8 IGNITION TIMING. IDLE SPEED .... B- 8 COMPRESSION .................... 8-10 INSPECTION ..................... B-10 ON-VEHICLE MAINTENANCE ....... B-11 PREPARATION ................... B-11 TIMING BELT ..................... 8-12 CYLINDER HEAD GASKET ........ B-16 H LA ............................. 8-20 FRONT OIL SEAL ................. 8-24 REAR OIL SEAL .................. 8-26 REMOVAL ......................... 8-28 PROCEDURE .................... B-28 ENGINE STAND MOUNTING ......... 8-32 PREPARATION ................... 8-32 PROCEDURE .................... B-33 DISASSEMBLY ..................... B-35 PREPARATION ................... 8-35 AUXILIARY PARTS ............... 8-36 TIMING BELT ..................... 8-37 CYLINDER HEAD ................. 8-39 CYLINDER BLOCK (EXTERNAL PARTS) ............. 8-42 CYLINDER BLOCK .............. (INTERNAL PARTS) 8-44 .............. INSPECTION I REPAIR 8-47 ................... PREPARATION 8-47 ................. CYLINDER HEAD 8-47 .............. VALVE MECHANISM 8-48 ...................... CAMSHAFT B-51 HLA ............................. 8-53 ............... CYLINDER BLOCK B-53 .......................... OIL JET B-54 PISTON. PISTON RING. AND ..................... PISTON PIN 8-55 CONNECTING ROD .............. B-56 ................... CRANKSHAFT 8-57 BEARING ........................ 8-57 TIMING BELT ..................... 8-58 TENSIONER. IDLER .............. 8-58 TENSIONER SPRING ............. 8-58 PULLEY ......................... 8-58 ........................ ASSEMBLY 8-59 ................... PREPARATION 8-59 CYLINDER BLOCK (INTERNAL PARTS) .............. B-60 CYLINDER BLOCK (EXTERNAL PARTS) ............. B-65 CYLINDER HEAD ................. B-69 TIMING BELT ..................... 8-73 ............... AUXILIARY PARTS 8-77 ..... ENGINE STAND DISMOUNTING 8-81 .................... PROCEDURE 8-81 INSTALLATION ..................... 8-83 .................... PROCEDURE 843 45UOBX-001 Gartner Banana

B INDEX INDEX 1. Timing belt Removal / Installation ....... page 8-1 2 2. Cylinder head gasket Replacement .............. page 6-1 6 3. HLA Removal / Installation ....... page 8-20 4. Front oil seal Replacement .............. page 6-24 5. Rear oil seal Replacement .............. page 6-26 INTAKE MANIFOLD COMPRESSION INSPECTION, PAGE B-10 TIGHTENING TORQUE STANDARD: 1,255 kPa (1 2.8 k f/cm2, 182 psi)-300 rpm 19-25 Nm (1.9-2.6 kgfq 14--18 ft4bf) MINIMUM: 883 kPa (9.0 kgflcm 9 , 128 psi}-300 rpm TIGHTENING TORQUE 3946 Nm i3.9--4.7 kgf m, 29-33 ftdbf) DRIVE BELT ADJUSTMENT. PAG ENGINE OIL INSPECTION, SERVICE, SECTION D DEFLECTION mm (in) ENGINE COOLANT INSPECTION, 6. Engine Removal .................. page 8-28 Engine stand mounting ..... page 6-32 Disassembly .............. page 6-35 Inspection / Repair ......... page B-47 Assembly ................. page 559 Engine stand dismounting ... page 8-81 , Installation ................ page B-83 SERVICE, SECTION E DRIVE BELT ALTERNATOR PIS. PIS + AlC AlC NEW 55-7.0 (0.224.27) 8.&9.0{0.324.35] 8.0-9.0{0.324.35) USED 6.0-7.5 (0.24-0.29) 9.0-10.0{0.364.39) 9.0-10.0{0.364.39} LIMIT 8.0 (0.31) 11.5 (0.45) 11.5 (0.453 Gartner Banana

OUTLINE, TROUBLESHOOTING GUIDE OUTLINE SPECIFICATIONS Engine Item Tv~e BP DOHC Gasoline, 4-cvcle . . I -, Dis~lacement ml kc. cu inl I 1.840 (1.840. 11 2) I Cylinder arrangement and number Combustion chamber Valve system Bore x stroke mm {in) I 83.0 x 85.0 (3.27 x 3.35) I In-line, 4-cylinders Pentroof DOHC, belt-driven Com~ression ratio I 9.0 I Compression pressure kPa (kgf/cm2, psi)-rpm .- . 1 open (BTDCO) 1,255 {I 2.8, 182)-300 5 Valve timing TROUBLESHOOTING GUIDE tX Valve clearance Problem .. . -. . Difficult starting ' With System Selector (49 B019 9AO) test switch at SELF TEST. 45uo~x-003 Close (ATDCO) IN mm {in) EX mm {in) Poor idling Close (ABDCO) Open (BBDCO) 14 0: Maintenance-free 0: Maintenance-free Excessive oil consumption 48 56 Possible Cause Malfunction of engine-related components Burned valve Worn piston, piston ring, or cylinder Failed cylinder head gasket Malfunction of fuel system Malfunction of ignition system Malfunction of engine-related components Malfunction of HLA' Poor valve-to-valve seat contact Failed cvlinder head aasket Oil leakage I Refer to section D I I Remedy Malfunction of fuel system Malfunction of ignition system Oil working up Worn piston ring groove or sticking piston ring Worn piston or cylinder Oil working down Worn valve seal Worn valve stem or guide Page Replace Replace or repair Replace Refer to section F Refer to section G Replace Replace or repair Re~lace 8-48 B-53,55 B-1 6 B-20 B-50 B-1 6 Refer to section F Refer to section G Replace Replace or repair Replace Replace B-55 B-53,55 B-39,70 8-48 Gartner Banana

B TROUBLESHOOTING GUIDE Problem nsufficlent power 4bnormal combustion Engine noise Possible Cause Insufficient compression Malfunction of HLA' Compression leakage from valve seat Seized valve stem Weak or broken valve spring Failed cylinder head gasket Cracked or distorted cylinder head Stuck, damaged, or worn piston ring Cracked or worn piston Malfunction of fuel system Malfunction of ignition system Others Slipping clutch Dragging brakes Wrong size tires Malfunction of engine-related components Malfunction of HLA* Stuck or burned valve Weak or broken valve spring Carbon accumulation in combustion chamber Malfunction of fuel system Malfunction of ignition system Crankshaft- or bearing-related parts Excessive main bearing oil clearance Main bearing seized or heat-damaged Excessive crankshaft end play Excessive connecting rod bearing oil clearance Connecting rod bearing seized or heat-damaged Piston-related parts Worn cylinder Worn piston or piston pin Seized piston Damaged piston ring Bent connecting rod Valves or timing-related parts Malfunction of HLA' Broken valve spring Excessive valve auide clearance Malfunction of cooling system Malfunction of fuel system Others Malfunction of water pump bearing Improper drive belt tension Malfunction of alternator bearing Exhaust gas leakage Malfunction of timina belt tensioner Remedy Replace Repair Replace Replace Replace Replace Replace Replace Refer to section F Refer to section G Refer to section H Refer to section P Refer to section Q Replace Replace Replace Eliminate carbon Refer to section F Refer to section G Replace or repair Replace Replace or repair Replace or repair Replace Replace or repair Replace Replace Replace Replace Replace Replace Replace Refer to section E Refer to section F Refer to section E Adjust Refer to section G Refer to section F Replace Page Tappet noise may occur if the engine has set idle for an extended period. The noise should dissipate after the engine has reached normal operating temperature. (HLA troubleshooting: Refer to page 6-8) Gartner Banana

ENGINE TUNE-UP B lgnition Timing 1. Connect the SST and set the TEST SW to "SELF TEST or connect data link connector terminals TEN and GND with a ium~er wire. ~ 4 2. Check the'idle speed, and set it to specification if neces- sary. (Refer to section F.) ldle speed (Neutral): 800-900 (850 + 50) rpm [MT] (P range): 750-450 (800 + 50) rpm [AT] 3. Verify that the timing mark (White) on the crankshaft pulley and the timing belt cover are aligned. lgnition timing: BTDC 9"-11" (1 0" + 1 ") 4. If the marks are not aligned, loosen the crankshaft posi- tion sensor lock bolt, and turn the crankshaft position sensor to make the adjustment 5. Tighten the crankshaft position sensor lock bolt to the specified torque. Tightening torque: 19-25 N.m {I .9--2.6 kgf.m, 1 &-I8 ft-lbf) 6. Disconnect the SST. 7. Verify that the ignition timing is within the specification. Ignition timing: BTDC 6-18" ldle Speed 1. Connect the SST and set the TEST SW to "SELF-TEST or connect data link connector terminals TEN and GND with a jumper wire. 2. Verify that the idle speed is within specification. ldle speed (Neutral): 800-900 (850 + 50) rpm [MT] (P range): 75-50 (800 -e 50) rpm [AT] 3. If the idle speed is not within specification, remove the blind cap from the air adjusting screw and adjust it. 4. After adjusting the idle speed, install the blind cap and disconnect the SST or jumper wire from the data link connector. Gartner Banana

COMPRESSION COMPRESSION If the engine exhibits low power, poor fuel economy, or poor idle, check the following: 1. Ignition system (Refer to section G.) 2. Compression (Refer to page B-10.) 3. Fuel system (Refer to section F.) INSPECTION 1. Check that the battery is fully charged. Recharge it if necessary. (Refer to section G.) 2. Warm up the engine to the normal operating tempera- ture. 3. Turn the engine OFF. 4. Remove all spark plugs. 5. Disconnect the ignition coil connector. 6. Connect a compression gauge to the No.1 spark plug hole. 7. Fully depress the accelerator pedal and crank the en- gine. 8. Record the maximum gauge reading. 9. Check each cylinder, as above. Compression: 1,255 kPa (1 2.8 kgf/cm2, 182 psi)-300 rpm Minimum: 883 kPa (9.0 kgf/cm2, 128 psiF300 rpm Differential limit between cylinders: 196 kPa (2.0 kgf/cm2, 28 psi} 10. If the compression in one or more cylinders is low, pour a small amount of engine oil into the cylinder and re- check the compression. (1) If the compression increases, the piston, piston rings, or cylinder wall may be worn. (2) If the compression stays low, the valve may be stuck or seated improperly. (3) If the compression in adjacent cylinders stays low, the cylinder head gasket may be defective or the cyl- inder head distorted. 11 . Connect the ignition coil connector. 12. Install the spark plugs. Tightening torque: 15--22 N.m (1.5-2.3 kgf.m, 11-16 ftlbf) Gartner Banana