1997 Subaru WRX / WRX STI Service & Repair Manual

1.8L & 2.2L 4-CYL Article Text 1998 Subaru Impreza ARTICLE BEGINNING 1995-98 ENGINES Subaru - 1.8L & 2.2L 4-Cylinder 1995-97: Impreza (1.8L) 1995-98: Impreza (2.2L), Legacy (2.2L) * PLEASE READ THIS FIRST * NOTE: For engine repair procedures not covered in this article, see ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION article in the GENERAL INFORMATION section. ENGINE IDENTIFICATION Engine can be identified by sixth character of Vehicle Identification Number (VIN). The VIN is stamped on a metal plate located on right front side of firewall. Engine identification number is stamped on a machined pad on left rear of cylinder block. ENGINE IDENTIFICATION CODE ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Application VIN Code 1995 1.8L ................................................. 2 2.2L ................................................. 6 1996 1.8L AWD ................................................ 2 FWD ................................................ 1 2.2L AWD ................................................ 4 FWD ................................................ 3 1997 1.8L ................................................. 2 2.2L AWD ................................................ 4 FWD ................................................ 3 1998 2.2L AWD ................................................ 4 FWD ................................................ 3 ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

ADJUSTMENTS VALVE CLEARANCE ADJUSTMENT NOTE: Engines on 1995-96 models are equipped with hydraulic lash adjusters. Valve adjustment is not required. NOTE: Perform valve adjustment when engine is cold. 1997-98 Models Disconnect battery ground cable. Remove connector from mass airflow sensor. Remove air intake duct and upper air cleaner cover as a unit. Remove air filter. Disconnect washer fluid pump wire connector and hose. Remove washer fluid tank. Remove right side timing belt cover. Remove spark plug wires. 2) Raise and support vehicle. Remove undercovers. Disconnect PCV hoses and remove valve covers. Set No. 1 cylinder to TDC of compression stroke. Arrow mark on right-side camshaft sprocket should be pointing up. See Fig. 1. Using feeler gauge, measure No. 1 cylinder valve clearance. Adjust as needed. Tighten lock nut to 78-95 INCH lbs. (9-11 N.m). See VALVE CLEARANCE SPECIFICATION. 3) Rotate crankshaft 180 degrees clockwise (camshaft turns 90 degrees) so the next cylinder in firing order is at TDC, and check/adjust valve clearance for that cylinder. See Fig. 1. Repeat procedure until all valves have been adjusted. Fig. 1: Identifying Camshaft/Cylinder Top Dead Center Positions Courtesy of Subaru of America, Inc. VALVE CLEARANCE SPECIFICATION ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Application Clearance In. (mm)

Intake ............................. .0070-.0087 (.18-.22) Exhaust ............................ .0091-.0106 (.23-.27) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ REMOVAL & INSTALLATION * PLEASE READ THIS FIRST * NOTE: For reassembly reference, label all electrical connectors, vacuum hoses and fuel lines before removal. Also place mating marks on engine hood and other major assemblies before removal. FUEL PRESSURE RELEASE 1995-97 Models Disconnect fuel pump wiring connector located under rear seat. Start engine and let idle until it stalls. Crank engine for an additional 5 seconds. Turn ignition off. 1998 Models Disconnect fuel pump relay connector located under left side of dash. Start engine and run until it stalls. Crank engine for an additional 5 seconds. Turn ignition off. ENGINE NOTE: Transaxle remains in vehicle with engine removal. Removal 1) Release fuel pressure. See FUEL PRESSURE RELEASE. Drain cooling system. Disconnect battery and remove from vehicle. Remove air intake duct/upper air cleaner cover assembly. Disconnect radiator and heater hoses. Disconnect A/T cooler lines (if equipped). Remove radiator. 2) Identify, mark and disconnect electrical connectors, vacuum hoses and fuel lines that interfere with engine removal. Discharge A/C system using approved refrigerant recovery/recycling equipment. Disconnect accelerator cable, cruise control cable (if equipped) and clutch cable/hill holder cable at clutch release fork (M/T). 3) Remove accessory drive belts. Remove power steering pump with hoses attached and set aside. Remove hoses from A/C compressor and set aside. Raise and support vehicle. Remove front exhaust pipe. Disconnect engine mount from front crossmember. Remove nuts attaching lower engine to transaxle. 4) Remove all brackets interfering with engine removal.

Remove flywheel access cover. Disconnect bolts securing drive plate to torque converter (A/T). Support engine using hoist. Support transaxle using floor jack. Remove bolts attaching upper side of engine to transmission. Remove engine. Installation To install, reverse removal procedure. Tighten bolts and nuts to specification. See TORQUE SPECIFICATIONS. Adjust all control cables. Check all fluid levels. INTAKE MANIFOLD Removal & Installation 1) Release fuel pressure. See FUEL PRESSURE RELEASE. Remove "V" belt. Disconnect negative battery cable. Remove air intake duct/upper air cleaner cover assembly. Disconnect throttle cable. Disconnect cruise control cable (if equipped). Remove power steering belt. Remove power steering pump with hoses attached and set aside. 2) Disconnect PCV and ventilation hoses. Disconnect spark plug wires. Disconnect coolant hoses and air by-pass hose from throttle body. Disconnect electrical connectors and vacuum hoses interfering with intake manifold removal. 3) Remove EGR pipe. Disconnect fuel hoses from pipes. Remove intake manifold-to-cylinder head bolts. Remove intake manifold. To install, reverse removal procedure. Use NEW gaskets. Tighten bolts to specification. See TORQUE SPECIFICATIONS. EXHAUST MANIFOLD NOTE: Exhaust manifold is integral with cylinder head. CYLINDER HEAD Removal Release fuel pressure. See FUEL PRESSURE RELEASE. Drain engine coolant. Remove timing belt and camshaft sprocket. See TIMING BELT. Remove intake manifold and exhaust pipe. See INTAKE MANIFOLD. Remove cylinder head bolts in reverse order of tightening sequence. See Fig. 2. Remove cylinder head and gasket. Inspection Check cylinder head warpage and height. Resurface head if warpage exceeds specification. See CYLINDER HEAD table under ENGINE SPECIFICATIONS. Replace cylinder head if height is not within specification. Installation Ensure mating surfaces are clean and dry. Install head

gasket. Coat head bolt threads with oil. Tighten bolts to specification in sequence. See Fig. 2. See TORQUE SPECIFICATIONS. To complete installation, reverse removal procedure. Fig. 2: Cylinder Head Bolt Tightening Sequence Courtesy of Subaru of America, Inc. TIMING BELT Removal 1) Remove generator drive belt. Remove A/C belt and tensioner, if equipped. Remove crankshaft pulley. If engine is removed from vehicle, crankshaft can be held using Crankshaft Pulley Wrench (499977000). Fig. 3: Identifying Crankshaft Pulley & Timing Belt Covers Courtesy of Subaru of America, Inc.

2) Remove left, right and front timing belt covers. See Fig. 3. If timing belt is to be reused, mark belt to indicate original direction of rotation before removal, if original marks are worn away or faded. Also mark belt to indicate belt-to-sprocket alignment, if original marks are worn away or faded. See Fig. 4. Fig. 4: Identifying Timing Belt Components Courtesy of Subaru of America, Inc. 3) To mark belt, turn crankshaft with Crankshaft Socket (499987500) to align marks on crankshaft sprocket and left and right camshaft sprockets with notches on timing belt cover and engine block. See Fig. 5. Fig. 5: Aligning Crankshaft Sprocket & Left & Right Camshaft Sprocket Marks Courtesy of Subaru of America, Inc.

4) Use White paint to mark direction of rotation and to mark timing belt in relation to sprocket timing marks. When marks are properly aligned, 44 teeth should be on right side of crankshaft sprocket and 40.5 teeth should be on left side of crankshaft sprocket. See Fig. 6. Fig. 6: Aligning Timing Belt Before Removal (Impreza) Courtesy of Subaru of America, Inc. 5) Loosen tensioner adjuster mounting bolts. Remove belt idler, and belt idler No. 2. Remove timing belt. Remove upper belt idler. Remove belt tensioner and spacer. Remove belt tensioner adjuster. See Fig. 7 Fig. 7: Removing Timing Belt Tensioner Components Courtesy of Subaru of America, Inc.

Inspection 1) Inspect timing belt for wear on rounded edges of drive teeth. Inspect belt for signs of oil contamination. Replace belt if it is damaged or contaminated. Inspect belt tensioner adjuster oil seals for leaks. Inspect rod ends for abnormal wear and scratches. Timing belt bend radius must be greater than 2.36" (60.0 mm). See Fig. 8. 2) Slight trace of oil at rod oil seal does not indicate a problem. While holding tensioner with both hands, push rod section against floor or wall using a force of 33-110 lbs. (15-50 kg) to ensure rod section does not move. 3) If rod section moves, replace tensioner adjuster with a NEW one. Measure extension of rod beyond body. Rod extension should be .606-.646" (15.40-16.40 mm). Replace belt tensioner adjuster if extension of rod is not as specified. Inspect belt tensioner and belt adjuster rod mating surface. Check spacer and tensioner bushing for wear. Fig. 8: Measuring Timing Belt Bend Radius Courtesy of Subaru of America, Inc. Installation CAUTION: DO NOT allow press pressure to exceed 2205 lbs. (992 kg). DO NOT release pressure until stopper pin is completely installed. 1) Ensure timing marks are aligned. Using a press, push rod into body until holes in belt tensioner adjuster rod and adjuster body are aligned. Install .059" (1.50 mm) diameter stopper pin into holes in adjuster body and rod. See Fig. 9. 2) Install belt tensioner adjuster, and temporarily tighten mounting bolts while tensioner adjuster is pushed completely to the right. Install belt tensioner and spacer. Install upper belt idler. Ensure crankshaft and camshaft alignment marks are aligned. See Fig. 5 . 3) Install timing belt, being careful not to move sprockets. Ensure rotation direction of belt is correct and that all alignment marks are aligned when belt is installed. See Fig. 6. Install belt

idler No. 2 and belt idler. Loosen tensioner adjuster mounting bolts and push tensioner adjuster completely left. Tighten tensioner adjuster mounting bolts. 4) Ensure marks on timing belt and sprockets align. See Fig. 6. Remove stopper pin from tensioner adjuster. Install timing belt covers, crankshaft pulley and generator drive belt. Install A/C belt and tensioner, if equipped. Remove rocker covers, and ensure valve lash adjuster does not contain air. Fig. 9: Installing Tension Adjuster Rod Stopper Pin Courtesy of Subaru of America, Inc. ROCKER ARM ASSEMBLY Removal & Installation 1) Disconnect PCV hose, and remove rocker cover. Loosen, but DO NOT remove, bolt No. 1. See Fig. 10. Remove rocker bolts No. 2-4 in order. Remove bolts No. 5-8. Remove rocker arm assembly. 2) On models with hydraulic lash adjusters, ensure rocker arm assembly air vent remains facing upward or submerge rocker arm assembly in clean engine oil. 3) To install, reverse removal procedure. DO NOT allow rocker arm assembly to gouge dowel/alignment pins. Tighten bolts in reverse order of loosening sequence to specification. See Fig. 10. See TORQUE SPECIFICATIONS. Fig. 10: Rocker Bolt Loosening Sequence Courtesy of Subaru of America, Inc.

CAMSHAFT Removal Remove timing belt, valve covers and camshaft sprockets. See TIMING BELT. NOTE: The following procedure is for removal of left camshaft. Procedure for right camshaft is similar. Remove rocker arm assembly. See ROCKER ARM ASSEMBLY. Remove camshaft position sensor. Remove valve lash adjusters and submerge in clean engine oil (if equipped). Remove oil dipstick tube mounting bolt. Remove camshaft support and "O" ring. Remove camshaft. Remove oil seals only if necessary. Inspection 1) Place camshaft in "V" blocks. Measure bend. Bend limit is .001" (.025 mm). Check cam face condition. Remove minor burrs by grinding using oil stone. Check cam height and journal for damage or wear. 2) Measure outside diameter of camshaft journal and inside diameter of cylinder head journal to determine camshaft oil clearance. If clearance is not within specification, replace camshaft or cylinder head as necessary. See CAMSHAFT under ENGINE SPECIFICATIONS. 3) Measure camshaft end play. If end play is not within specification, replace camshaft support. Installation 1) Apply a coat of clean engine oil to camshaft journals. Install camshaft. Lubricate "O" ring and Install to camshaft support. Install camshaft support. 2) Apply grease to oil seal lips. Using Oil Seal Guide (499597000) and Oil Seal Installer (499587100), install oil seal on camshaft support. To complete installation, install rocker cover, timing belt, camshaft sprockets and related parts. Perform necessary adjustments. OIL PAN Removal & Installation Drain oil. Remove oil pan bolts. Remove oil pan and gasket. To install, reverse removal procedure using NEW gasket. Tighten bolts to specification. See TORQUE SPECIFICATIONS. WATER PUMP Removal 1) Disconnect negative battery cable. Drain engine coolant.

1997 Subaru WRX / WRX STI Service & Repair Manual

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