INFINITI / NISSAN & MERCURY 3.3L V6 (2024)

MANUFACTURER'S SUGGESTED SCHEDULED MAINTENANCE

The manufacturer recommends the timing belt be replaced at 105,000 mile intervals.

REMOVAL & INSTALLATION

TIMING BELT

Removal (Frontier, Pathfinder, QX4 & Xterra)

1. Disconnect negative battery cable. Remove the engine undercover. Drain coolant and remove the radiator. Remove engine cooling fan and water pump pulley. Remove accessory drive belts. Remove spark plugs.
2. Remove distributor protector. Remove A/C compressor drive belt idler bracket. Remove fresh air intake tube from rocker cover. Remove thermostat housing hose.
3. Rotate crankshaft to set No. 1 cylinder at TDC on compression stroke. See Fig.1. Remove crankshaft pulley bolt and remove crankshaft pulley. Remove front upper and lower timing belt covers. See Fig.2.
4. Align punch mark on left camshaft sprocket with punch mark on timing belt upper rear cover. Align punch mark on crankshaft sprocket with notch on oil pump housing. See Fig.3. Install crankshaft pulley bolt so that crankshaft can be rotated.
5. Loosen timing belt tensioner nut. See Fig.4. Turn tensioner, and remove timing belt.

Fig. 1: Setting Crankshaft To TDC
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig. 2: Exploded View Of Timing Belt & Components
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig. 3: Aligning Camshaft & Crankshaft Punch Marks
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig. 4: Loosening Timing Belt Tensioner Nut
Courtesy of NISSAN MOTOR CO., U.S.A.

Inspection (Frontier, Pathfinder, QX4 & Xterra)

Check timing belt for cracks and broken or worn teeth. Check belt tensioner for smooth turning. Check condition of tensioner spring. Replace parts as necessary.

Installation (Frontier, Pathfinder, QX4 & Xterra)

1. Install timing belt when engine is cold. Ensure No. 1 cylinder is at TDC on compression stroke. Crankshaft sprocket mark should align with mark on rear cover. See Fig.5. If removed, install timing belt tensioner and tensioner spring.

NOTE:

If stud for tensioner spring is removed, apply thread sealant to stud threads before installing.

2. Turn tensioner clockwise fully outward with hexagon wrench, and temporarily tighten lock nut. Align White lines on timing belt with punch marks on camshaft sprockets and crankshaft sprocket. See Fig.6. Point arrow on timing belt toward front belt cover. There should be 40 teeth between left and right camshaft sprockets, and 43 teeth between left camshaft sprocket and crankshaft sprocket.
3. If engine was overhauled or reassembled (rocker covers removed), go to step 6. If only the timing belt was replaced, go to next step.
4. Loosen tensioner lock nut. Using hex wrench, turn tensioner clockwise and counterclockwise at least 2 times. Tighten tensioner lock nut. Turn crankshaft clockwise at least 2 revolutions, then slowly set No. 1 cylinder at TDC on compression stroke. Apply 22 lbs. (10 kg) of force to belt (downward direction) midway between camshaft sprockets. Belt deflection should be 0.51-0.59" (13-15 mm). If not, readjust belt tension.
5. Install lower and upper belt covers. Install crankshaft pulley. Tighten bolt to specification. See TORQUE SPECIFICATIONS. To complete installation, reverse removal procedures. Fill and bleed cooling system. See COOLING SYSTEM BLEEDING. Adjust drive belts to proper tension.
6. Loosen rocker shaft bolts to relieve belt tension caused by camshafts. Loosen tensioner lock nut. Using Allen wrench, rotate tensioner by turning Allen wrench clockwise 70-80 degrees. Temporarily tighten lock nut. Rotate crankshaft clockwise at least 2 revolutions.
7. Slowly return cylinder No. 1 to TDC of compression stroke. Using Push/Pull Gauge (J-38387), apply 22 lbs. (10 kg) of pressure to timing belt between right camshaft sprocket and tensioner. Hold tensioner in position with Allen wrench, and loosen tensioner lock nut.
8. Place a .0206" (.5 mm) feeler gauge under tensioner pulley between pulley and timing belt, and rotate crankshaft clockwise until feeler gauge is centered between tensioner pulley and timing belt (timing belt will move about 2.5 teeth). See Fig.7. Tighten tensioner lock nut to specification. See TORQUE SPECIFICATIONS.
9. Rotate crankshaft to remove feeler gauge. Rotate crankshaft clockwise at least 2 revolutions, then slowly set cylinder No. 1 at TDC of compression stroke. While applying 22 lbs. (10 kg) of pressure, measure timing belt deflection halfway between camshaft sprockets. If deflection is not .51-.59" (13-15 mm), repeat steps 6-8. To complete installation, reverse removal procedure. Fill and bleed cooling system. See COOLING SYSTEM BLEEDING. Adjust drive belts to proper tension.

Fig. 5: Positioning Camshaft & Crankshaft Sprockets
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig. 6: Installing Timing Belt
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig. 7: Adjusting Timing Belt
Courtesy of NISSAN MOTOR CO., U.S.A.

Removal (Quest & Villager)

1. Raise and support vehicle. Remove the engine undercover. Remove right side wheel and engine side cover. Drain coolant from radiator. Remove accessory drive belts.
2. Rotate crankshaft to set No. 1 cylinder at TDC on compression stroke. See Fig.1. Remove crankshaft pulley bolt, and remove crankshaft pulley using a gear puller.
3. Remove upper radiator hose and water inlet hose from timing belt end of engine. Remove A/C compressor drive belt idler bracket. Remove water pump pulley. Remove breather pipe from timing belt front upper cover. Remove front upper and lower belt covers. See Fig.2.
4. Align punch mark on left camshaft sprocket with punch mark on timing belt upper rear cover. Align punch mark on crankshaft sprocket with notch on oil pump housing. See Fig.3. Temporarily install crankshaft pulley bolt so that crankshaft can be rotated.
5. Loosen timing belt tensioner nut. See Fig.4. Turn tensioner, and remove timing belt.

   NOTE:

   After removing timing belt, DO NOT turn crankshaft or camshaft separately, or valves will strike pistons.

Inspection (Quest & Villager)

Check timing belt for cracks and broken or worn teeth. Check belt tensioner for smooth turning. Check condition of tensioner spring. Replace parts as necessary.

Installation (Quest & Villager)

1. Install timing belt when engine is cold. Ensure No. 1 cylinder is at TDC on compression stroke. Crankshaft sprocket mark should align with mark on rear cover. See Fig.5. If removed, install timing belt tensioner and tensioner spring.

   NOTE:

   If stud for tensioner spring is removed, apply thread sealant to stud threads before installing.

2. Turn tensioner clockwise fully outward with hexagon wrench, and temporarily tighten lock nut. Align white lines on timing belt with punch marks on camshaft sprockets and crankshaft sprocket. See Fig.6. Point arrow on timing belt toward front belt cover. There should be 40 teeth between left and right camshaft sprockets, and 43 teeth between left camshaft sprocket and crankshaft sprocket.
3. Loosen tensioner lock nut. Using hex wrench, turn tensioner clockwise and counterclockwise at least 2 times. Tighten tensioner lock nut. Turn crankshaft clockwise at least 2 revolutions, then slowly set No. 1 cylinder at TDC on compression stroke. Apply 22 lbs. (10 kg) of force to belt (downward direction) midway between camshaft sprockets. Belt deflection should be 0.51-0.59" (13-15 mm). If not, readjust belt tension.
4. Install lower and upper belt covers. Install crankshaft pulley. Tighten bolt to specification. See TORQUE SPECIFICATIONS. To complete installation, reverse removal procedures. Fill and bleed cooling system. See COOLING SYSTEM BLEEDING. Adjust drive belts to proper tension.

COOLING SYSTEM BLEEDING

Frontier, Pathfinder, QX4 & Xterra (1999-02)

1. If vehicle is equipped with manual A/C, move temperature control lever to full HOT position. If vehicle is equipped with automatic A/C, turn ignition on. Remove air relief plug on intake manifold collector. See Fig.8. On Pathfinder, remove heater hose from heater core inlet. See Fig.9. On all models, fill radiator slowly until coolant starts to drip from air relief plug. Tighten air relief plug to 61-69 INCH lbs. (7-8 N.m). On Pathfinder, install heater hose to heater core inlet.
2. On all models, fill radiator and coolant reservoir tank to MAX mark. Install and tighten radiator cap. Start and run engine until warm. Run engine at 3000 RPM for at least 10 seconds (repeat 2-3 times). Stop engine and allow it to cool. Refill radiator and coolant reservoir as necessary.
3. Repeat previous step at least 3 times with temperature control lever at several different positions between full COLD and full HOT positions. System is full when water noise is no longer heard at heater core and coolant level no longer drops.

Fig. 8: Locating Air Relief Plug (Frontier, Pathfinder, QX4 & Xterra)
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig. 9: Locating Heater Core Inlet Hose (Frontier, Pathfinder, QX4 & Xterra)
Courtesy of NISSAN MOTOR CO., U.S.A.

Frontier & Xterra (2003-04)

1. Ensure radiator is completely empty of coolant and water. Install radiator drain plug, and tighten to 71-106 INCH lbs. (8-12 N.m). If removed, apply sealant to threads of cylinder block drain plugs, and tighten to 25-33 ft. lbs. (34-44 N.m). Install reservoir tank, if necessary. Tighten air relief plug to 62-71 INCH lbs. (7-8 N.m). See Fig.8. Reattach upper radiator hose at engine side.
2. Set vehicle heater controls to full HOT and heater ON positions. Turn ignition on (engine off) to activate heater mode. Install Coolant Refill Tool (J-45695) by installing radiator cap adapter onto radiator neck opening. Attach gauge body assembly with refill tube and venturi assembly to radiator cap adapter. See Fig.10.

CAUTION:

Compressed air supply must be equipped with an air dryer.

3. Insert refill hose into coolant mixture container that is placed at floor level. Ensure ball valve is in closed position. Install air hose to venturi assembly, and adjust air pressure to 80-120 psi (5.6-8.4 kg/cm²).
4. The vacuum gauge will begin to rise and there will be an audible hissing noise. During this process, open ball valve on refill hose slightly. Coolant will be visible rising in refill hose. Once refill hose is full of coolant, close the ball valve. This will purge any air trapped in refill hose.
5. Continue to draw vacuum until gauge reaches 28 inches of vacuum. In high altitude locations, the gauge may not reach 28 inches. See VACUUM GAUGE SPECIFICATIONS table.

   VACUUM GAUGE SPECIFICATIONS
   

   Altitude Above Sea Level	Vacuum Gauge Reading
   0-328 Ft. (0-100 m)	28 Inches
   984 Ft. (300 m)	27 Inches
   1641 Ft. (500 m)	26 Inches
   3281 Ft. (1000 m)	24-25 Inches

6. When vacuum gauge has reached specified amount, disconnect air hose and wait 20 seconds to see if the system loses any vacuum. If vacuum level drops, repair system as necessary and repeat steps 3-5. Recheck for leaks.

CAUTION:

DO NOT allow coolant container to get too low when filling, or air will be drawn into cooling system.

7. Place coolant container (with refill hose inserted) at same level as top of radiator. Open ball valve on refill hose so the coolant will be drawn up to fill cooling system. Cooling system is full when vacuum gauge reads zero. Remove tool assembly from radiator neck opening.
8. Fill cooling system reservoir tank to specified level. See COOLING SYSTEM SPECIFICATIONS table. Run engine to warm up the cooling system, and top up as necessary before installing radiator cap.

COOLING SYSTEM SPECIFICATIONS

Fig. 10: Installing Coolant Refill Tool (J-45695)
Courtesy of NISSAN MOTOR CO., U.S.A.

Quest & Villager

1. Install radiator drain plug. If removed, apply sealant to threads of cylinder block drain plug and tighten to 25-33 ft. lbs. (34-44 N.m). Slowly add coolant through radiator filler neck allowing several minutes for air to escape. Add fluid until filler neck is full.
2. Continue adding coolant while gently moving upper radiator hose up and down until coolant no longer lowers in filler neck. Place wire under radiator filler cap negative pressure relief valve. See Fig.11. Install radiator cap. Disconnect coolant reservoir hose from radiator neck overflow port.
3. Attach clear hose to modified one gallon bottle. Using locking pliers, clamp hose. Fill bottle with coolant and hang it from hood latch. Remove locking pliers and let coolant flow until it comes out of radiator air relief plug. Reclamp hose.
4. Close engine air relief plug if not already done. Tighten air relief plug to specification. See TORQUE SPECIFICATIONS. Raise front wheel off ground, with front bumper 22" (558 mm) off of ground. Ensure radiator cap (with wire) is installed.
5. On vehicles with manual heater, ensure temperature control lever is in full HOT position. Set fan speed to HIGH and airflow to head/feet position. On vehicles with automatic heater, set temperature controls to 90°F and fan speed to HIGH.
6. Remove locking pliers. Start and run engine at 1500 RPM, until cooling fan turns on.
7. On all models, stop engine. Fill coolant reservoir to MAX mark. Remove modified one gallon bottle. Lower vehicle. Let engine cool down. Remove radiator cap and remove wire from negative pressure valve. Fill radiator as necessary and reinstall radiator cap. Fill reservoir as necessary and install reservoir cap. Check for leaks.

Fig. 11: Holding Negative Pressure Relief Valve Open (Quest & Villager)
Courtesy of NISSAN MOTOR CO., U.S.A.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS