1998 Mercedes-Benz SL500 (4.2L & 5.0L) Service and Repair Manual

4.2L & 5.0L V8 Article Text 1998 Mercedes-Benz SL500 For 1 Copyright © 1998 Mitchell Repair Information Company, LLC Friday, September 02, 2011 03:15PM ARTICLE BEGINNING 1997-98 ENGINES Mercedes-Benz 4.2L & 5.0L V8 1997: E420 1997-98: S420, S500, SL500 1998: CL500 * 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 The engine family designation is shown on the emission control information plate (attached to radiator crossmember). The 1st character identifies the model year ("V" for 1997 or "W" for 1998) while the 6th, 7th and 8th characters identify the engine displacement. ENGINE IDENTIFICATION CODES Application & Engine Size (1) Engine ID Engine Code 1997 E420 (4.2L) ............... 119.985 ........................ (2) S420 (4.2L) ............... 119.981 ........................ (2) S500 (5.0L) ............... 119.980 ........................ (2) 1998 CL500 (5.0L) .............. 119.980 ........................ (2) S420 (4.2L) ............... 119.981 ........................ (2) S500 (5.0L) ............... 119.980 ........................ (2) SL500 (5.0L) .............. 119.982 ........................ (2) (1) - The engine identification number must be used when ordering replacement parts. (2) - Information not available. ADJUSTMENTS VALVE CLEARANCE ADJUSTMENT Hydraulic valve lifters are used and valve clearance adjustment is not necessary. CAMSHAFT BASIC TIMING

4.2L & 5.0L V8 Article Text (p. 2) 1998 Mercedes-Benz SL500For 1 Copyright © 1998 Mitchell Repair Information Compan 1) Position cylinder No. 1 to 45 degrees BTDC. Remove both valve covers. Using Camshaft Pins (119 589 00 15 00), pin all camshafts. Camshaft pins are installed through camshaft bearing cap No. 1. If camshaft basic timing is okay, all camshaft pins should have been installed. 2) If any camshaft pin could not be installed, remove both top slide rails. See TOP SLIDE RAIL (TIMING CHAIN GUIDE) under REMOVAL & INSTALLATION. Remove timing chain tensioner. See CHAIN TENSIONER under REMOVAL & INSTALLATION. NOTE: To enable adjustment of camshafts, slack in timing chain (from removing timing chain tensioner) must be moved to left side of engine by rotating camshafts. 3) To start adjustment of camshaft timing, use Wrench (119 589 00 01 00) to rotate slack area in timing chain to left exhaust camshaft by rotating one at a time (in direction of engine rotation) right exhaust camshaft, right intake camshaft, then left intake camshaft. 4) When left intake camshaft is properly positioned, reposition timing chain onto left exhaust camshaft gear and install camshaft pin. Rotate left intake camshaft so camshaft pin can be installed. Reposition timing chain onto left intake camshaft. 5) Rotate right intake camshaft so camshaft pin can be installed. Reposition timing chain onto right intake camshaft. Rotate right exhaust camshaft so camshaft pin can be installed. Reposition timing chain onto right exhaust camshaft. 6) All camshaft pins should be installed and piston No. 1 should be at 45 degrees BTDC. If camshafts did not align allowing installation of camshaft pins and piston No. 1 is not at 45 BTDC, repeat procedure. VALVE TIMING NOTE: Valve timing is measured with hydraulic lifters installed. Checking 1) Measure valve timing at intake valves No. 1 and 6. Remove valve covers. Rotate crankshaft in direction of engine rotation until lobes of intake cams being tested are facing up (only base circles resting on hydraulic lifters). 2) Attach a dial indicator with tip resting vertically on cylinder No. 1 intake valve hydraulic lifter. Preload dial indicator . 12" (3 mm) and zero dial. Ensure tip moves freely. Rotate crankshaft in direction of engine rotation until dial indicator reads .08" (2 mm) valve lift. 3) With .08" (2 mm) intake valve lift (valve opening), crankshaft should indicate specification in VALVE TIMING SPECIFICATIONS table. Continue rotating crankshaft until intake valve starts closing. Crankshaft should indicate specification in VALVE TIMING SPECIFICATIONS table. Repeat steps 2) and 3) for cylinder No. 6 intake valve.

4.2L & 5.0L V8 Article Text (p. 3) 1998 Mercedes-Benz SL500For 1 Copyright © 1998 M 4) Attach a dial indicator so tip is resting vertically on cylinder No. 1 exhaust valve hydraulic lifter. Preload dial indicator .12" (3 mm) and zero dial. Ensure tracer pin moves freely. Rotate crankshaft in direction of engine rotation until dial indicator reads .08" (2 mm) valve lift. 5) With .08" (2 mm) exhaust valve lift (valve opening), crankshaft should indicate specification in VALVE TIMING SPECIFICATIONS table. Continue rotating crankshaft until exhaust valve starts closing. Crankshaft should indicate specification in VALVE TIMING SPECIFICATIONS table. Repeat steps 4) and 5) for cylinder No. 6 exhaust valve. 6) If valve timing is not to specification, ensure hydraulic lifters are functioning properly. Replace hydraulic lifters as necessary. If hydraulic lifters are okay, check timing chain for excessive stretching. Replace timing chain if necessary. VALVE TIMING SPECIFICATIONS Engine Crankshaft Degrees 4.2L Intake Valve Opens (1) .................................. 30 ATDC Intake Valve Closes (1) ................................. 35 ABDC Exhaust Valve Opens ...................................... 8 BBDC Exhaust Valve Closes .................................... 13 BTDC 5.0L Intake Valve Opens (1) .................................. 30 ATDC Intake Valve Closes (1) ................................. 40 ABDC Exhaust Valve Opens ..................................... 13 BBDC Exhaust Valve Closes .................................... 13 BTDC (1) - With camshaft adjuster retarded. REMOVAL & INSTALLATION * PLEASE READ THIS FIRST * NOTE: For reassembly reference, label all electrical connectors, vacuum hoses and fuel lines before removal. FUEL PRESSURE RELEASE Turn ignition off. Disconnect fuel pump(s) negative terminal (located under vehicle). If necessary, remove cover to access fuel pump(s). Start engine. Allow engine to run until it stalls. Crank engine to ensure residual fuel pressure is released. ENGINE NOTE: Procedure covers removing engine and transmission as a single unit.

4.2L & 5.0L V8 Article Text (p. 4) 1998 Mercedes-Benz SL500For 1 Copyright © 1998 Mitchell Repair Removal 1) Release fuel pressure. See FUEL PRESSURE RELEASE under REMOVAL & INSTALLATION. Raise hood to vertical position. Disconnect battery terminals. Remove air filter. If vehicle is equipped with A/C, discharge A/C system and recover refrigerant. 2) Remove engine compartment covering from under vehicle. Drain and remove radiator. Loosen 2 drains located next to engine mounts. Drain engine coolant from engine. If vehicle is equipped with A/C, place a guard over A/C condenser. 3) Disconnect heater hose at intake manifold. Disconnect heater hose from rear of crankcase. Cap heater hose and engine connections to prevent contamination. 4) Remove viscous fan clutch and fan. If vehicle is equipped with A/C, remove A/C drive belt. Disconnect fuel lines. Disconnect engine wiring harness connectors. 5) Disconnect vacuum lines as necessary. Disconnect accelerator cable. Disconnect brake servo vacuum line. Using a siphon, remove power steering fluid from power steering pump reservoir. Disconnect power steering pump hydraulic lines at pump. 6) Disconnect air injection (if equipped). On E420, remove front bumper assembly and right headlight. Disconnect left engine mount cooling air duct. On CL500, S420 and S500, disconnect oil cooler line bracket. 7) On all models, disconnect oil cooler lines at air-to-oil cooler. On E420, disconnect left oil cooler line at oil sump. On all models, if vehicle is equipped with self-leveling suspension, disconnect high pressure hose at oil sump. On E420, disconnect left oil line for automatic transmission. 8) On all models, if vehicle is equipped with A/C, remove A/C compressor mounting bolts and/or nut. Secure A/C compressor aside with A/C hoses connected. Disconnect Heated Oxygen Sensor (HO2S) connector(s). Completely remove exhaust system. 9) Remove shield over starter (if equipped). Disconnect starter electrical connections. Disconnect generator electrical connections. On E420, disconnect strut located below oil sump. On all models, disconnect drive shaft from flexible coupling at transmission. Leave flexible coupling connected to transmission. 10) Loosen drive shaft center bearing bolts. Loosen large clamping nut on drive shaft. Clamping nut is located near center bearing. With clamping nut loosened, push drive shaft as far back from transmission as possible. 11) Disconnect transmission ground strap. Turn starter lockout switch locking element before disconnecting starter lockout switch connector. See Fig. 1. Using 2 screwdrivers, pry off starter lockout switch connector from transmission. 12) Remove rear engine support. Remove exhaust bracket from transmission. Disconnect shift linkage at transmission. Disconnect electrical connections from transmission. 13) Ensure all necessary electrical, vacuum and mechanical connections are disconnected. Unbolt front engine mounts. Attach chain hoist to lifting eyes of engine and take up slack. Remove engine and

4.2L & 5.0L V8 Article Text (p. 5) 1998 Merce transmission by repositioning engine hoist several times. Installation To install, reverse removal procedure. Adjust all fluid levels. Fig. 1: Identifying Starter Lockout Switch Connector Locking Element Courtesy of Mercedes-Benz of North America. BELT TENSIONER Removal & Installation Loosen belt tensioner adjustment bolt (accessible from top front of engine). Remove belt. Remove bolt from center front of belt tensioner (accessible from front of engine). Pull belt tensioner forward, removing belt tensioner. To install, reverse removal procedure. Tighten bolt to specification. See TORQUE SPECIFICATIONS. INTAKE MANIFOLD NOTE: Removal and installation procedure is not available. EXHAUST MANIFOLD Removal & Installation (Right Side) Disconnect negative battery cable. Disconnect dipstick guide tube from exhaust manifold. Disconnect exhaust manifold from exhaust pipe. Remove exhaust manifold retaining bolts. Raise engine slightly to assist in removal of exhaust manifold. Remove exhaust manifold. To install, reverse removal procedure. Install NEW exhaust manifold gasket with metal side facing cylinder head. Removal & Installation (Left Side)

1998 Mercedes-Benz SL500 (4.2L & 5.0L) Service and Repair Manual

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