The Nissan Z20 or Z20S is a carbureted 2.0 liter (1,952 cc; 121.9 cu-in) liquid-cooled, straight-four, four-stroke cycle, gasoline engine from the Nissan Z-family. The Z20 engine was manufactured from 1979 through 1984. It replaced the Nissan L20B while using many of the same components.
The Nissan Z20S engine features a cast-iron block and aluminum alloy cylinder head with two ignition plugs per cylinder, but for some commercial vehicles, a single-spark plug head was used. It has a single overhead camshaft and 8 valves (2 per cylinder).
It has an 85.0 mm (3.34 in) cylinder bore and 86.0 mm (3.38 in) piston stroke with a compression ratio of 8.5:1 or 9.3:1. The Z20S engine produced up to 110.0 PS (88.0 kW, 108.0 HP) at 5,200 rpm of max. horsepower and 161.0 Nm (16.4 kg·m; 118.8 lbf·ft) at 3,200 rpm of peak torque.
The breakdown of the engine code is as follows:
- Z – Engine Family
- 20 – 2.0 Liter Displacement
- S – Carburetor
General information
| Engine Specifications | |
| Engine code | Z20S |
| Layout | Four stroke, Inline-4 (Straight-4) |
| Fuel type | Gasoline |
| Production | 1979-1984 |
| Displacement | 2.0 L, 1,952 cc (121.9 cu-in) |
| Max. horsepower | 110.0 PS (88.0 kW, 108.0 HP) at 5,200 rpm |
| Max. torque | 161.0 Nm (16.4 kg·m; 118.8 lbf·ft) at 3,200 rpm |
| Fuel system | Carburetor |
| Power adder | None |
| Cooling system | Liquid-cooling |
| Firing order | 1-3-4-2 |
| Dimensions (L x H x W): | – |
| Weight | – |
Cylinder block
The Z20S engine has a cast-iron cylinder block, bore is 85.0 mm (3.34 in) and stroke is 86.0 mm (3.38 in). The cylinder block, a monoblock specially cast structure, employs the five bearing support system. The pistons are each fitted with two compression rings and a single oil ring.
| Cylinder block | ||
| Cylinder block alloy | Cast iron | |
| Compression ratio: | 8.5:1 or 9.3:1 | |
| Cylinder bore: | 85.0 mm (3.34 in) | |
| Piston stroke: | 86.0 mm (3.38 in) | |
| Number of piston rings (compression / oil): | 2 / 1 | |
| Number of main bearings: | 5 | |
| Cylinder inner diameter (standard): | 85.000-85.050 mm (3.3465-3.3484 in) | |
| Piston skirt diameter (standard): | 84.985-85.035 mm (3.3459-3.3478 in) | |
| Piston pin outer diameter: | 20.993-20.998 mm (0.8265-0.8267 in) | |
| Piston ring side clearance: | Top | 0.040-0.073 mm (0.0016-0.0029 in) |
| Second | 0.030-0.063 mm (0.0012-0.0025 in) | |
| Oil | – | |
| Piston ring end gap: | Top | 0.25-0.40 mm (0.0098-0.0157 in) |
| Second | 0.15-0.30 mm (0.0059-0.0118 in) | |
| Oil | 0.30-0.90 mm (0.012-0.035 in) | |
| Crankshaft journal diameter: | 54.942-54.955 mm (2.1631-2.1336 in) | |
| Crankpin diameter: | 49.961-49.974 mm (1.9670-1.9675 in) | |
| Crankshaft center distance: | 42.97-43.03 mm (1.6917-1.6941 in) | |
Cylinder head
The cylinder head is made of a light, strong aluminum alloy with good cooling efficiency. Intake valves are 42.0 mm in diameter and the exhaust valves are 38.0 mm.
| Cylinder head | ||
| Valve Arrangement: | SOHC, chain drive | |
| Valves: | 8 (2 valves per cylinder) | |
| Intake/Exhaust duration: | 248°/248° | |
| Valve head diameter: | INTAKE | 42.0-42.2 mm (1.654-1.661 in) |
| EXHAUST | 38.0-38.2 mm (1.496-1.4504 in) | |
| Valve length: | INTAKE | 122.8-123.1 mm (4.835-4.846 in) – Datsun 510 124.1-124.4 mm (4.885-4.898 in) – Nissan 720 |
| EXHAUST | 123.6-123.9 mm (4.866-4.878 in) – Datsun 510 125.1-125.4 mm (4.925-4.937 in) – Nissan 720 | |
| Valve stem diameter: | INTAKE | 7.965-7.980 mm (0.3136-0.3142 in) |
| EXHAUST | 7.945-7.960 mm (0.3128-0.3134 in) | Cam height: | INTAKE/EXHAUST | 38.477-38.527 mm (1.5148-1.5168 in) – Datsun 510 38.481-38.531 mm (1.5150-1.5170 in) – Nissan 720 |
| Outer camshaft journal diameter: | 32.935-32.955 mm (1.2967-1.2974 in) | |
Tightening torque specs
| Tightening torque specs | |
| Front cover bolt | M8: 10-16 Nm; 1.0-1.6 kg·m; 7-12 ft·lb M6: 3.9-9.8 Nm; 0.4-1.0 kg·m; 2.9-7.2 ft·lb |
| Chain guide bolt | 5.9-9.8 Nm; 0.6-1.0 kg·m; 4.3-7.2 ft·lb |
| Chain tensioner bolt | 5.9-9.8 Nm; 0.6-1.0 kg·m; 4.3-7.2 ft·lb |
| Water pump bolt | M8: 10-16 Nm; 1.0-1.6 kg·m; 7-12 ft·lb M6: 3.9-9.8 Nm; 0.4-1.0 kg·m; 2.9-7.2 ft·lb |
| Crank pulley bolt | 118-157 Nm; 12-16 kg·m; 87-116 ft·lb |
| Water inlet bolt | 10-16 Nm; 1.0-1.6 kg·m; 7-12 ft·lb |
| Water outlet bolt | 10-16 Nm; 1.0-1.6 kg·m; 7-12 ft·lb |
| Intake manifold bolt and nut | 16-21 Nm; 1.6-2.1 kg·m; 12-15 ft·lb |
| Alternator bracket bolt | 39-59 Nm; 4.0-6.0 kg·m; 29-43 ft·lb |
| Alternator to adjusting bar bolt | 20-29 Nm; 2.0-3.0 kg·m; 14-22 ft·lb |
| Engine mounting bracket bolt | 29-39 Nm; 3.0-4.0 kg·m; 22-29 ft·lb |
| Exhaus manifold bolt and nut | 16-21 Nm; 1.6-2.1 kg·m; 12-15 ft·lb |
| EGR tube nut | 34-44 Nm; 3.5-4.5 kg·m; 25-33 ft·lb |
| EAI tube nut | 34-44 Nm; 3.5-4.5 kg·m; 25-33 ft·lb |
| Cylinder head bolt | 69-78 Nm; 7.0-8.0 kg·m; 51-58 ft·lb |
| Cylinder head to front cover bolt | 3.9-7.5 Nm; 0.4-0.7 kg·m; 2.9-5.8 ft·lb |
| Rocker shaft bracket bolt | 15-25 Nm; 1.5-2.5 kg·m; 11-18 ft·lb |
| Camshaft sprocket bolt | 118-157 Nm; 12-16 kg·m; 87-116 ft·lb |
| Rocker arm nut | 16-22 Nm; 1.6-2.2 kg·m; 12-16 ft·lb |
| Main bearing cap bolt | 44-54 Nm; 4.5-5.5 kg·m; 33-40 ft·lb |
| Connecting rod big end nut | 44-54 Nm; 4.5-5.5 kg·m; 33-40 ft·lb |
| Gusset to cylinder block | 43-58 Nm; 4.4-5.9 kg·m; 32-43 ft·lb |
| Flywheel bolt (M/T) | 137-157 Nm; 14-16 kg·m; 101-116 ft·lb |
| Drive plate bolt (A/T) | 137-157 Nm; 14-16 kg·m; 101-116 ft·lb |
| Clutch cover bolt (M/T) | 16-21 Nm; 1.6-2.1 kg·m; 12-15 ft·lb |
| Torque coverter bolt (A/T) | 39-49 Nm; 4.0-5.0 kg·m; 29-36 ft·lb |
| Starter motor bolt | 29-39 Nm; 3.0-4.0 kg·m; 22-29 ft·lb |
| Transmission to cylinder block bolt | 43-58 Nm; 4.4-5.9 kg·m; 32-43 ft·lb |
| Transmission to gusset bolt | 43-58 Nm; 4.4-5.9 kg·m; 32-43 ft·lb |
Maintenance data
| Valve clearance (HOT) | |
| Intake valve | 0.30 mm (0.012 in) |
| Exhaust valve | 0.30 mm (0.012 in) |
| Compression pressure | |
| Standard | 12.0 kg/cm2 (11.77 bar, 171 psi) / 350 rpm |
| Minimun | 9.0 kg/cm2 (8.83 bar, 128 psi) / 250 rpm |
| Oil system | |
| Oil consumption , L/1000 km (qt. per miles) | up to 0.5 (1 qt. per 1200 miles) |
| Recommended engine oil | 5W-30 5W-40 10W-30 10W-40 |
| Oil type API | SE |
| Engine oil capacity (Refill capacity) | With filter change: 4.4 liters (4.6 US.qts, 3.9 Imp. qts) Without filter change: 3.9 liters (4.1 US.qts, 3.4 Imp. qts) |
| Oil change interval, km (miles) | 5,000-10,000 (3,000-6,000) |
| Ignition system | |
| Ignition timing (B.T.D.C./rpm) | 6-12°/600 rpm (depends on the country and vehicle model) |
| Spark plug | Cold: BP7ES, BPR7ES (NGK) Standard: BP6ES, BPR6ES (NGK) Hot: BP5ES, BPR5ES (NGK) |
| Spark plug gap | 0.8-0.9 mm (0.03 -0.035 in) |
| Spark plug tightening torque | 15-20 Nm; 1.5-2.0 kg·m; 11-14 ft·lb |
Vehicle applications
| Model | Years Produced |
| Datsun 510 | 1979-1981 |
| Datsun 720 | 1981 |
| Nissan Cabstar | – |
| Nissan / Datsun Caravan, Urvan, Hony (E23) | 1980-1986 |
| Nissan Laurel C230 | 1979-1980 |
| Nissan Laurel C31 | 1980-1984 |
| Datsun D21 | – |
Author:
can you guys please upload sequence for adjusting tappets?
(NISSAN Z20 S )
I sent you this information on the e-mail
can’t find ignition wiring diagram for the “z24s”….any ideas ??
Sent by e-mail.
Is there an engine manual for this motor
Hello great site can u send me the sequence for setting tappers on a Z20 engine please. Regards Ray
Hello is there a manual for the motor z20(s)?
Will carburetor for z20 work on l20b motor or other way around?
Many thanks
Trent
Hi Dear admin
I need a repare manual or catalog can you help me ?
Hi,
Do you have specs for contact breaker point gap setting please ? (Z20S Nissan Caravan 87)
Thank you
Admin, is there a service manual for this engine i.e Z20? Thanks in advance