3.0l v6 - VIN [v] Toyota 4Runner II

ENGINE IDENTIFICATION

Note. For engine repair procedures not covered in this article, see ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION article in the GENERAL INFORMATION section.

Engine may be identified by Vehicle Identification Number (VIN) stamped on a metal pad, located near lower left corner of windshield. The fourth character of VIN identifies engine model. See ENGINE IDENTIFICATION CODES table.

Engine identification number, located on left front corner of cylinder block, near oil filter, may be required when ordering replacement parts.

ENGINE IDENTIFICATION CODES

VALVE CLEARANCE ADJUSTMENT

Note. Adjust valve clearance with engine cold.

Scheme 18

Scheme 19

Scheme 20

1. Disconnect throttle position sensor connector. Release fuel pressure. See «FUEL PRESSURE RELEASE»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v__fuel-pressure-release) under REMOVAL & INSTALLATION. Disconnect vacuum and fuel lines at fuel pressure regulator. Disconnect PCV hose at union.
2. Drain cooling system. Remove coolant hoses from intake manifold and coolant by-pass pipe. Remove cold start injector tube. Disconnect EGR temperature sensor connector (Calif. only) and vacuum hoses at air pipe and vacuum modulator.
3. Remove EGR valve assembly. Disconnect hose from reed valve. Remove air intake chamber retaining bolts. Remove air intake chamber. (Scheme 21)
4. Label and unplug electrical connectors. Remove engine wiring harness across front of engine. Remove valve covers and spark plugs. Rotate crankshaft pulley, and align pulley groove with "0" mark on timing belt cover to set cylinder No. 1 at TDC of compression stroke.
5. Ensure cylinder No. 1 valve lifters are loose and cylinder No. 4 valve lifters are tight. If valve lifters are not as described, rotate crankshaft 360 degrees, and realign timing marks.
6. Measure and record clearance of exhaust valve on cylinder No. 2 and intake valve on cylinder No. 6. (Scheme 18) Rotate crankshaft pulley 120 degrees (1/3 of a revolution). Measure and record clearance of intake valve on cylinder No. 1 and exhaust valve on cylinder No. 3.
7. Rotate crankshaft pulley 120 degrees (1/3 of a revolution). Measure and record clearance of intake valve on cylinder No. 2 and exhaust valve on cylinder No. 4.
8. Rotate crankshaft pulley 120 degrees (1/3 of a revolution). Measure and record clearance of intake valve on cylinder No. 3 and exhaust valve on cylinder No. 5. Rotate crankshaft pulley 120 degrees (1/3 of a revolution). Measure and record clearance of intake valve on cylinder No. 4 and exhaust valve on cylinder No. 6.
9. Rotate crankshaft pulley 120 degrees (1/3 of a revolution). Measure and record clearance of intake valve on cylinder No. 5 and exhaust valve on cylinder No. 1.
10. Ensure clearance is within specification. See «VALVE CLEARANCE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table. If clearance adjustment is required, rotate crankshaft pulley so camshaft lobe on valve to be adjusted faces up. VALVE CLEARANCE SPECIFICATIONS Application (1) In. (mm) Exhaust Valve.009-.013 (.22-.32) Intake Valve.007-.011 (.18-.28) (1) Adjust valve clearance with engine cold.
11. Position adjusting shim notch area in direction in which shim will be removed. Use Valve Clearance Adjuster (09248-55010) and SST (A) to press valve lifter down. (Scheme 19) Install SST (B) between camshaft and valve lifter. Remove SST (A). Using a small screwdriver and magnet, remove adjusting shim.
12. Using micrometer, measure thickness of shim removed. Determine correct thickness of replacement shim to be used by subtracting appropriate valve clearance specification from measured valve clearance. See «VALVE CLEARANCE SPECIFICATION»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table. Add this number to thickness of old shim. Select a new shim with a thickness as close as possible to the calculated value. See «SHIM THICKNESS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table.
13. Install proper shim. Using SST (A), press downward on valve lifter and remove SST (B). Recheck valve clearance. SHIM THICKNESS Thickness mm (in.) Shim No. 2.20 (0.0866) 01 2.25 (0.0886) 03 2.30 (0.0906) 05 2.35 (0.0925) 07 2.40 (0.0945) 09 2.45 (0.0965) 11 2.50 (0.0984) 13 2.55 (0.1004) 15 2.60 (0.1024) 17 2.65 (0.1043) 19 2.70 (0.1063) 21 2.75 (0.1083) 23 2.80 (0.1102) 25 2.85 (0.1122) 27 2.90 (0.1142) 29 2.95 (0.1161) 31 3.00 (0.1181) 33 3.05 (0.1201) 35 3.10 (0.1220) 37 3.15 (0.1240) 39 3.20 (0.1260) 41 3.25 (0.1280) 43 3.30 (0.1299) 45 3.35 (0.1319) 47 3.40 (0.1339) 49
14. Install gasket on valve cover. Apply sealant to indicated areas on cylinder head. (Scheme 20) Install valve cover. Install air intake chamber with new gaskets.
15. Install EGR valve and gaskets, and tighten designated bolts to specification. (Scheme 25) To install remaining components, reverse removal procedure. Tighten all nuts and bolts to specification. See «TORQUE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table.

REMOVAL & INSTALLATION

Note. For installation 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

Disconnect negative battery cable. Place container under the fitting that will be loosened. Use a rag to cover fuel line and component. Slowly loosen fitting, allowing pressurized fuel to flow into container. After fuel system has been depressurized, disconnect and plug fitting.

ENGINE

Note. Engine and transmission should be removed as an assembly.

Removal

1. Disconnect negative battery cable. Drain cooling system. Remove radiator. Remove air cleaner assembly. Remove all drive belts and fan pulley. Mark all electrical connectors and vacuum hoses for installation reference, and then disconnect them.
2. Release fuel pressure. See «FUEL PRESSURE RELEASE»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v__fuel-pressure-release) under REMOVAL & INSTALLATION. Disconnect fuel inlet and return hoses. Disconnect accelerator cable. Disconnect throttle and cruise control cables (if equipped). Remove power steering pump and A/C compressor with hoses connected (if equipped).
3. On M/T models, remove shift levers. Disconnect clutch release cylinder hose. On all models, place alignment marks on drive shafts and companion flange. Remove drive shafts. Disconnect heater hoses. On A/T models, disconnect shift linkage.
4. On all models, disconnect speedometer cable. Remove front crossmember. On 4WD models, remove transfer case shift linkage, and remove stabilizer bar. Remove front floor heat insulator and brakeline heat insulator. On all models, disconnect oxygen sensor connector.
5. Remove exhaust pipe from exhaust manifold and catalytic converter. Support transmission with a jack. Remove transmission mount bolts and rear crossmember. Support engine with hoist. Remove engine mount bolts. Lift engine and transmission out of vehicle.

Installation

To install, reverse removal procedure. Tighten all nuts and bolts to specification. See TORQUE SPECIFICATIONS table. Refill fluid levels. Check for leaks.

1. Disconnect negative battery cable. Remove air cleaner. Drain cooling system, and remove radiator. Remove all drive belts. Remove power steering pump with hoses connected (if equipped).
2. Remove fan, fan clutch and fan pulley. Mark all electrical connectors on engine wiring harness for installation reference, and then disconnect them. Label vacuum hoses, and disconnect them from intake manifold and cylinder head.
3. Release fuel system pressure. See «FUEL PRESSURE RELEASE»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v__fuel-pressure-release) under REMOVAL & INSTALLATION. Disconnect fuel inlet and return hoses. Disconnect accelerator cable. Disconnect throttle and cruise control cables (if equipped).
4. Disconnect clutch release (slave) cylinder hose (if equipped). Disconnect heater hoses. Disconnect oxygen sensor connector. Remove front exhaust pipe from exhaust manifold and catalytic converter.
5. Remove timing belt. See «TIMING BELT»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) under REMOVAL & INSTALLATION. Mark distributor and spark plug wires for installation reference, and remove them. Disconnect coolant hoses from air intake chamber.
6. Remove cold start injector connector and cold start injector tube from air intake chamber. Remove EGR valve assembly. Remove reed valve hoses. Remove air intake chamber.
7. Remove engine wiring harness from front of engine. Remove No. 2 and 3 fuel pipes. (Scheme 21) Remove No. 4 timing belt cover, No. 2 idler pulley and No. 3 timing belt cover. (Scheme 22)and (Scheme 23). Remove oil dipstick guide bolt from left side of cylinder head.
8. Remove fuel delivery pipes, injectors and delivery pipe spacers. Remove coolant by-pass outlet. (Scheme 21) Remove intake manifold bolts/nuts, and remove intake manifold. Remove exhaust crossover pipe between exhaust manifolds. CAUTION: Cylinder head bolts must be loosened in proper sequence to prevent cylinder head warping or cracking.
9. Remove reed valve and air injection manifold on right cylinder head. Remove alternator. Remove valve cover and camshaft housing rear cover. (Scheme 21) Using proper sequence, loosen cylinder head bolts in 3 steps. (Scheme 24) Remove cylinder head. Remove exhaust manifold.

Scheme 21

Scheme 22

Scheme 23

Inspection

1. Measure cylinder head warpage. Replace cylinder head if warpage exceeds specification. See «CYLINDER HEAD»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS.
2. Check intake and exhaust manifolds and air intake chamber warpage. If warpage exceeds specification, replace appropriate component(s). See «WARPAGE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table.

WARPAGE SPECIFICATIONS

1. Ensure mating surfaces are clean and dry. Ensure No. 1 piston is at TDC and camshafts are timed correctly. See «TIMING BELT»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v). Install cylinder head gasket. Coat cylinder head bolt threads with oil. Using several steps, tighten cylinder head bolts, except bolt "A", in sequence to 32 ft. lbs. (44 N.m). (Scheme 24)
2. Place a mark on top of cylinder head bolts, toward the front. Tighten bolts 90 degrees, in sequence. Ensure mark on cylinder head bolt is pointing to the side. Tighten bolts an additional 90 degrees, in sequence. Ensure mark on cylinder head bolt faces rearward. Install bolt "A", and tighten it to 27 ft. lbs. (37 N.m).
3. Install alternator, air suction reed valve, oil dipstick guide and exhaust crossover pipe. Connect knock sensor wire. Install intake manifold and coolant by-pass outlet.
4. Install new "O" rings on injectors. Coat "O" rings with gasoline before installing injectors in delivery pipes. Ensure injectors rotate smoothly in delivery pipe and intake manifold after installation.
5. Apply sealant to sealing surface of No. 2 idler pulley and No. 4 timing belt cover. Apply sealant to coolant outlet before installation. Install front and rear fuel pipes. Install timing belt. See «TIMING BELT»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) under REMOVAL & INSTALLATION. When installing valve cover, apply sealant to indicated areas on cylinder head. (Scheme 20)
6. Install air intake chamber. Install EGR valve and gaskets, and tighten designated bolts to specification. (Scheme 25) Install new "O" ring on distributor.
7. Align protrusion area on distributor driven gear with groove of distributor housing. Install distributor while aligning housing groove with groove of No. 4 camshaft bearing cap.
8. To install remaining components, reverse removal procedure. Tighten bolts to specification. See «TORQUE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table. Fill cooling system, and check for leaks.

Scheme 24

Scheme 25

Removal & Installation (Oil Pump Installed)

1. Remove timing belt and crankshaft timing pulley. See «TIMING BELT»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) under REMOVAL & INSTALLATION. Using a knife, cut off oil seal lip. Pry seal from oil pump housing. Use care not to damage crankshaft sealing surfaces.
2. To install new oil seal, apply grease to oil seal lip. Using Seal Installer (09309-37010), install oil seal until oil seal is even with oil pump body. To install remaining components, reverse removal procedure.

Removal & Installation (Oil Pump Removed)

Using hammer and drift, remove oil seal from oil pump housing. Apply grease to new oil seal lip. Using Seal Installer (09309-37010), install oil seal until oil seal is even with oil pump housing surface.

1. Drain cooling system and remove radiator. Remove all accessory drive belts. Remove power steering pump belt pulley. Remove power steering pump with hoses connected. Remove spark plugs. Disconnect hoses from air pipe.
2. Remove fan, belt guide and fan pulley. Remove spark plug wire clamps and remove No. 2 timing belt cover bolts and cover. (Scheme 26) Rotate engine until No. 1 cylinder is at TDC and groove on crankshaft pulley aligns with "O" mark on No. 1 timing belt cover.
3. Ensure camshaft and No. 3 timing belt cover marks are aligned. (Scheme 27) If marks are not aligned, rotate crankshaft 360 degrees and recheck alignment.
4. Remove power steering belt pulley. Using Pulley Holder (SST 09213-58011) and Flange Holder (SST 09330-00021), hold crankshaft pulley and remove retaining bolt. Using puller, remove crankshaft pulley.
5. Remove fan pulley bracket. Remove No. 1 timing belt cover and gaskets. If timing belt is to be reused, place arrow on belt to indicate belt rotation and place alignment marks on all timing pulleys and timing belt. CAUTION: If timing belt is to be reused, place arrow to indicate belt rotation and alignment marks on all pulleys and timing belt.
6. Remove timing belt guide and tension spring. (Scheme 26) Loosen No. 1 idler pulley retaining bolt and move pulley to the left as far as possible and temporarily tighten bolt. Remove timing belt.
7. If camshaft timing pulleys require removal, use Holder (SST 09278-54012) to hold pulley while removing pulley retaining bolt. CAUTION: DO NOT use timing belt tension to hold timing belt pulley during retaining bolt removal or installation.
8. Remove camshaft timing belt pulley and pin. To remove crankshaft timing belt pulley, pry pulley off of crankshaft using 2 screwdrivers.

Scheme 26

Scheme 27

1. Inspect timing belt for wear on rounded edges of drive teeth. Inspect belt for signs of oil contamination. Replace belt if damaged or contaminated.
2. Inspect idler pulleys and fan pulley bracket for smooth rotation. For No. 2 idler pulley replacement, see «NO. 2 IDLER PULLEY»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) . Inspect idler pulley tension spring for damage and free length. Spring free length should be 2.15" (54.6 mm). Replace damaged components.

1. Install Woodruff key in crankshaft, if removed. Using Crankshaft Pulley Installer (SST 09214-60010), install crankshaft timing pulley. Align groove of crankshaft timing pulley with cavity of the oil pump. (Scheme 27)
2. Install No. 1 idler pulley and position to the left as far as possible and temporarily tighten bolt. Align camshaft pin holes with reference marks on No. 3 timing belt cover. (Scheme 28)
3. Install camshaft timing pulleys and retaining bolts. DO NOT install pins at this time. Ensure head of retaining bolt does not contact the pulley. Align pulley reference mark with mark on No. 3 timing belt cover. (Scheme 27)
4. Install timing belt. If used belt is being installed, ensure belt is installed in proper direction of rotation and reference marks placed on the belt are aligned with all pulleys.
5. Loosen No. 1 idler pulley bolt and pry pulley toward the right as far as possible and temporarily tighten bolt. Install tension spring. Loosen No. 1 idler pulley bolt until pulley moves with spring force tension.
6. Temporarily install crankshaft pulley bolt and rotate crankshaft clockwise 2 full revolutions. Ensure all timing pulley marks are properly aligned. (Scheme 27) Tighten No. 1 idler pulley bolt to 27 ft. lbs. (37 N.m).
7. Remove camshaft timing pulley retaining bolts. Align camshaft pin holes with hole of pulley. Install pin and retaining bolt. Using Pulley Holder (SST 09278-54012), hold pulley and tighten bolt to specification. DO NOT use timing belt to hold pulley while tightening.
8. Remove crankshaft pulley bolt. Install timing belt guide with the cupped side facing toward front of engine. To install remaining components, reverse removal procedure. Tighten bolts to specification. See «TORQUE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table. Apply sealant to coolant outlet before installation.

Scheme 28

1. Disconnect throttle position sensor connector. Release fuel pressure. See «FUEL PRESSURE RELEASE»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v__fuel-pressure-release) under REMOVAL & INSTALLATION. Disconnect vacuum and fuel lines at pressure regulator. Disconnect PCV hose at union.
2. Drain cooling system. Remove coolant hoses from intake manifold and coolant by-pass pipe. Remove cold start injector tube. Remove EGR gas temperature sensor connector (Calif. only) and vacuum hoses at air pipe and EGR vacuum modulator.
3. Remove EGR valve assembly. Disconnect hose from reed valve. Remove air intake chamber retaining bolts. (Scheme 21) Unplug electrical connectors, and remove engine wiring harness across front of engine.
4. Remove front fuel pipe. Remove No. 4 timing belt cover. (Scheme 22) Remove No. 2 idler pulley retaining bolts. Remove No. 2 idler pulley.

To install, reverse removal procedure. Apply sealant to sealing surface of No. 2 idler pulley. Install pulley. Tighten bolts to specification. See TORQUE SPECIFICATIONS table.

1. Remove timing belt and camshaft timing pulleys. See «TIMING BELT»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) under REMOVAL & INSTALLATION. Remove air intake chamber.
2. Remove No. 2 idler pulley. See «NO. 2 IDLER PULLEY»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) under REMOVAL & INSTALLATION. Remove No. 3 timing belt cover retaining bolts and timing belt cover. Remove camshaft housing rear cover.
3. Remove all other hoses, electrical connectors, vacuum lines and components necessary to access valve covers. Remove valve covers. Loosen camshaft bearing cap bolts in sequence, in 3 steps. (Scheme 29)
4. Note camshaft bearing cap arrow direction for reassembly reference. (Scheme 30) Remove bearing caps and camshaft. Remove valve lifters and shims from cylinder head. Mark component location for installation reference.

Scheme 29

1. Clean camshaft journals and cylinder head journal surfaces. Inspect journals for damage. Measure camshaft lobe height and runout at center camshaft journal. Replace camshaft if lobe height and runout are not within specification. See «CAMSHAFT»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS.
2. Using Plastigage method, check camshaft oil clearance. Install camshaft and bearing caps. Ensure bearing caps are installed with arrows on caps pointing toward front (right side) and rear (left side). (Scheme 30)
3. Tighten bearing caps in sequence to 12 ft. lbs. (16 N.m) in 3 steps. (Scheme 29) Remove bearing caps, and check clearance. Replace cylinder head or camshaft if clearance is not within specification. See «CAMSHAFT»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table. With camshaft installed, check camshaft end play. Replace camshaft or cylinder head if end play exceeds specification.
4. Determine oil clearance between cylinder head and valve lifter. Replace components if clearance is not within specification. See «VALVE LIFTERS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS.

Scheme 30

1. Coat oil seal lip and bearing journals with oil. Install camshaft on cylinder head. Install oil seal on front of camshaft. Install camshaft housing plug. Apply sealant to No. 1 and No. 3 bearing caps. (Scheme 20)
2. Install bearing caps. Ensure arrows on caps point toward front on right side and rear on left side. (Scheme 30) Install bearing cap bolts. Slightly tighten bolts in small increments using proper sequence to secure components during oil seal installation. (Scheme 29)
3. Using Seal Installer (09214-60010), drive in camshaft oil seals. (Scheme 29) Using proper sequence, tighten bearing cap bolts to specification in small increments. See «TORQUE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table. Recheck camshaft end play. When installing valve cover, apply sealant to indicated areas on cylinder head. (Scheme 20)
4. To complete installation, reverse removal procedure. Tighten bolts and nuts to specification. Check and adjust valve clearance if necessary. See «VALVE CLEARANCE ADJUSTMENT»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v__valve-clearance-adjustment).

1. If rear oil seal retainer is removed from cylinder block, use a hammer and screwdriver to remove oil seal. Apply multipurpose grease to new oil seal. Using Seal Installer (09223-41020), install oil seal.
2. If rear oil seal retainer is still on cylinder block, disconnect negative battery cable. Remove transmission. Place reference mark on clutch pressure plate (M/T) and flywheel for installation reference. Remove pressure plate, clutch disc (if equipped) and flywheel/drive plate.
3. Using a knife, cut off oil seal lip. Carefully pry oil seal out of retainer. Use care not to damage crankshaft surface. Apply multipurpose grease to new seal. Using Seal Installer (09223-41020), install new oil seal until flush with oil seal retainer edge.

1. Drain cooling system. Remove timing belt. See «TIMING BELT»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) under REMOVAL & INSTALLATION. Remove No. 1 idler pulley. Remove radiator hose at thermostat housing.
2. Remove coolant inlet, gasket and thermostat. Remove water pump bolts and water pump.

1. Ensure water pump bearing rotates smoothly. Apply sealant to water pump sealing area. Install water pump. Install bolts and tighten them to specification. See «TORQUE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table.
2. Install thermostat with valve facing upward. Install coolant inlet and gasket. Tighten bolts to specification. Install remaining components.

Note. For more information on cooling systems, see ELECT FAN & SYSTEM SPECS article in the ENGINE COOLING Section.

1. On 4WD models, front differential must be removed. See appropriate article in the DRIVE AXLES Section. On all models, drain engine oil. Remove oil pan retaining bolts. CAUTION: DO NOT damage baffle plate flange during removal.
2. Using Seal Cutter (09032-00100) and brass drift, separate oil pan from cylinder block. If oil pan baffle plate requires removal, remove oil strainer. Using seal cutter and brass drift, separate baffle plate from cylinder block.

1. Apply sealant to sealing surface of baffle plate. Install baffle plate, oil strainer and gasket. Tighten bolts to specification. Apply one continuous bead of Sealant (08826-00080) to oil pan mating surface.
2. Apply sealant to inner surface around bolt hole area. Tighten oil pan bolts to specification. See «TORQUE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table. To complete installation, reverse removal procedure. Fill engine with oil. Start engine, and check for leaks.

CYLINDER HEAD OVERHAUL

1. Remove and disassemble cylinder head. See «CYLINDER HEAD & MANIFOLDS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) under REMOVAL & INSTALLATION. Remove camshaft bearing caps in sequence. (Scheme 29) Keep disassembled parts in removal order for reassembly. Mark parts for reassembly reference. CAUTION: DO NOT clean cylinder head in hot tank.
2. Inspect cylinder head for cracks. Thoroughly clean cylinder head gasket mating surfaces. Check cylinder head for warpage. If warpage exceeds specification, resurface or replace as necessary. See «CYLINDER HEAD»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS.

VALVE SPRINGS

Measure free length of valve springs. Check spring tension at specified height. Check valve spring out-of-square. Replace springs if measurements are not within specification. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS.

VALVE GUIDES

1. To obtain valve stem-to-valve guide oil clearance, subtract measured valve stem diameter from measured valve guide I.D. Replace valve guide and valve if oil clearance is not within specification. See «CYLINDER HEAD»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS. To replace valve guide, go to step 2). NOTE: Valve guide bore of cylinder head can be reamed to accommodate.002" (.05 mm) oversize replacement valve guide.
2. Insert an old valve wrapped with tape into valve guide. (Scheme 31) Tap valve firmly with hammer to break guide off flush with cylinder head surface. Be careful not to damage lifter bore. Remove snap ring.
3. Using water or oil bath, gradually heat cylinder head to about 194°F (90°C). Using Valve Guide Remover/Installer (09201-70010), drive guide out from camshaft side. Using telescopic hole gauge, measure inside diameter (I.D.) of cylinder head valve guide bore.
4. Valve guide bore I.D. should be.5118-.5129" (13.000-13.027 mm). If valve guide bore I.D. exceeds.5129" (13.027 mm), ream valve guide bore to.5138-.5148" (13.050-13.076 mm) for.002" (.05 mm) O/S guide.
5. To install new valve guide, heat cylinder head as explained previously in step 3). Using valve guide remover/installer, drive in new valve guide from camshaft side until snap ring contacts cylinder head. Using a sharp.31" (8.0 mm) reamer, ream valve guide until standard valve stem-to-guide oil clearance is obtained. See «CYLINDER HEAD»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS.

Scheme 31

Note. Always reface valve seat after replacing valve guide.

VALVE SEAT

1. Before refacing valve seats, inspect valves and valve guides. If measurements are not within specification, replace components as necessary. See «VALVES & VALVE SPRINGS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) and CYLINDER HEAD tables under ENGINE SPECIFICATIONS.
2. Inspect valve seat for evidence of pitting at valve contact surface. Reface seat as necessary. Valve seat replacement procedure is not available.

VALVES

Measure valve stem diameter, valve margin and overall length. Replace valves if measurements are not within specification. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS.

SEAT CORRECTION ANGLES

1. Replace valve guides, if necessary, before refacing valve seats. After refacing, if valve seat is too high on face of valve, use 30-degree and 45-degree stones/cutters to correct seat.
2. If valve seat is too low, use 60-degree and 30-degree stones/cutters to correct seat. Ensure valve seat margin is within specification. See «CYLINDER HEAD»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS.

PISTON & ROD ASSEMBLY

1. Before removing bearing caps, mark caps and rods with punch for reassembly reference. Measure connecting rod side play clearance with dial indicator. If clearance exceeds.015" (.38 mm), replace connecting rod and/or crankshaft.
2. Using a connecting rod aligner, check rod for bends or twists. Maximum bend limit is.0020" (.050 mm) per 3.94" (100.0 mm) length or less. Maximum twist limit is.0059" (.150 mm) per 3.94" (100.0 mm) length or less.
3. Install piston on connecting rod so that front mark on connecting rod aligns with FRONT mark on top of piston. (Scheme 32)

Scheme 32

FITTING PISTONS

1. Measure cylinder bore and piston skirt diameter. Piston skirt diameter should be measured at 90-degree angle to piston pin. Measure at approximately.921" (23.39 mm) from piston head. Ensure clearance between piston and cylinder bore is within specification. See «PISTONS, PINS & RINGS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS.
2. There are 3 standard piston sizes. Pistons may be identified by size mark ("1", "2" or "3") located on top of piston. (Scheme 32) When installing new piston into cylinder block that has not been bored for oversize, ensure size mark on new piston matches cylinder bore size mark stamped on left side of cylinder block, near each cylinder bore. (Scheme 33)

Scheme 33

PISTON RINGS

Ensure ring end gap and side clearance are within specification. See PISTONS, PINS & RINGS table under ENGINE SPECIFICATIONS. Ensure identification marks on rings are toward top of piston. Position piston rings at designated areas. (Scheme 34)

Scheme 34

ROD BEARINGS

1. Mark bearing cap and connecting rod for location. Remove connecting rod cap and bearing. Note size mark ("1", "2" or "3") stamped on connecting rod cap and bearing. (Scheme 36) If replacing standard size bearing, ensure number on replacement bearing is same as number on connecting rod cap and old bearing.
2. Different bearing sizes are used. Bearing size (thickness) is determined by size mark ("1", "2" or "3") stamped on connecting rod cap and bearing. See «CONNECTING ROD BEARING SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table.
3. Install replacement bearing. Install connecting rod cap with front mark toward front of engine. (Scheme 32) Using Plastigage method, check bearing clearance. See «CONNECTING RODS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS.
4. Tighten connecting rod nuts in 2 steps. Tighten rod nuts to 18 ft. lbs. (24 N.m). Place reference point on top of each connecting rod nut, and tighten each nut 90 degrees.
5. If connecting rod nut cannot be tightened to specification, or nut binds on connecting rod stud threads, replace connecting rod nuts and/or bolts. Check connecting rod side clearance. See «CONNECTING RODS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS.

Note. Install rod bearings with oil hole in the connecting rod.

CONNECTING ROD BEARING SPECIFICATIONS

CRANKSHAFT & MAIN BEARINGS

1. Mark connecting rod and main bearing caps for reassembly reference. Remove connecting rod caps and bearings. Note direction of arrow on main bearing cap.
2. Loosen main bearing cap bolts in 3 steps using proper sequence. (Scheme 35) Remove main bearing caps. Keep all bearing inserts in original location. Remove crankshaft. Remove main bearings from cylinder block. Mark bearings for location. CAUTION: Use size mark on crankshaft to determine journal diameter. (Scheme 36)
3. Inspect crankshaft for cracks. Check crankshaft for runout at center journal. If runout is greater than.0024" (.060 mm), replace crankshaft. Measure crankshaft journals out-of-round and taper. If either measurement exceeds.0008" (.020 mm), regrind and/or replace crankshaft.
4. Cylinder block main journal bore diameter is determined by size mark ("1", "2" or "3") stamped on oil pan rail of cylinder block. (Scheme 36) Main bearing journal diameter is determined by size mark ("0", "1" or "2") stamped on crankshaft counterweight. Size marks are placed in order with corresponding cylinders. (Scheme 36)
5. Ensure main bearing journal diameter is within specification. See «CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS. Install bearing with oil hole in the engine block.
6. Main bearings are available in.010" (.25 mm) and.020" (.50 mm) undersize. Install thrust washers on No. 2 main bearing cap, with oil grooves facing away from cap. Install main bearing cap with arrow pointing toward front of engine.
7. Tighten main bearing cap bolts to specification in sequence. See «TORQUE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v). Ensure crankshaft rotates smoothly. (Scheme 35) Check crankshaft end play. See CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS table under ENGINE SPECIFICATIONS.

Note. Install main bearing with oil hole in cylinder block.

Scheme 35

Scheme 36

THRUST BEARING

Check crankshaft end play. See CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS table under ENGINE SPECIFICATIONS. If end play exceeds maximum limit, replace thrust washers as a set and/or replace crankshaft. Thrust washers are installed on No. 2 main bearing journal.

CYLINDER BLOCK

1. Inspect cylinder block for cracks. Measure warpage, taper and out-of-round. Replace or repair cylinder block if measurements are not within specification. See «CYLINDER BLOCK»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table under ENGINE SPECIFICATIONS.
2. Measure cylinder bore. There are 3 standard cylinder bore sizes. Cylinder bore size (diameter) is determined by size mark ("1", "2" or "3") stamped on left side of block, near each cylinder bore. (Scheme 33) NOTE: If boring cylinder block, allow less than.0008" (.020 mm) in cylinder bore for final honing.
3. If cylinder bore is okay, hone cylinder to obtain a 60-degree crosshatch pattern. After honing, wash cylinder bore with hot soapy water. Air-dry cylinder bore, and apply engine oil to prevent rusting.

ENGINE LUBRICATION

Oil pressure is provided by a rotor-type pump, which is driven by the crankshaft. Pressure relief valve is located in the oil pump body. (Scheme 37)for cross-sectional view of engine oil circuit.

CRANKCASE CAPACITY

On 4WD models, crankcase oil capacity is 4.8 qts. (4.5L) with filter replacement. On 2WD models, crankcase capacity is 4.5 qts. (4.3L) with filter replacement.

NORMAL OIL PRESSURE

With engine at normal operating temperature, oil pressure should exceed 4 psi (.3 kg/cm 2 ) at idle and should be 36-75 psi (2.5-5.3 kg/cm 2 ) at 3000 RPM.

Scheme 37

Remove engine undercover (splash) shields. Remove oil pan and baffle. Remove timing belt and crankshaft timing pulley. See TIMING BELT under REMOVAL & INSTALLATION. Remove oil pump bolts. Remove oil pump and "O" ring from cylinder block.

1. Disassemble pump. Install rotors in pump body. Check rotor tip clearance and clearance between driven rotor and pump body. Place straightedge across pump body to check rotor side clearance.
2. Check clearance between straightedge and both rotors. Replace rotor set or pump assembly if any clearance measurement is not within specification. See «OIL PUMP SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/mechanical/#30l-v6-vin-v) table.

1. If oil seal was removed, coat new seal with grease, and install seal using Seal Installer (09309-37010). Reassemble pump. Install new "O" ring on front of cylinder block.
2. Apply Sealant (08826-00080) to rear of oil pump. Install oil pump on cylinder block. Ensure splined teeth of oil pump aligns with teeth of crankshaft. To complete installation, reverse removal procedure. Install bolts, and tighten them to specification.

OIL PUMP SPECIFICATIONS

GENERAL ENGINE SPECIFICATIONS

GENERAL SPECIFICATIONS

CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS SPECIFICATIONS

CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS

CONNECTING RODS SPECIFICATIONS

CONNECTING RODS

PISTONS, PINS & RINGS SPECIFICATIONS

PISTONS, PINS & RINGS

CYLINDER BLOCK SPECIFICATIONS

CYLINDER BLOCK

VALVES & VALVE SPRINGS SPECIFICATIONS

VALVES & VALVE SPRINGS

CYLINDER HEAD SPECIFICATIONS

CYLINDER HEAD

CAMSHAFT SPECIFICATIONS

CAMSHAFT

VALVE LIFTERS SPECIFICATIONS

VALVE LIFTERS

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

See also:
• ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION
• ENGINE IDENTIFICATION CODES
• FUEL PRESSURE RELEASE
• VALVE CLEARANCE ADJUSTMENT