Suzuki J18

The Suzuki J18 / J18A is a 1.8 L (1,840 cc, 112.3 cu·in) straight-four 4-stroke natural aspirated gasoline engine from the Suzuki J-family. The J18 engine was manufactured by Suzuki Motor Corporation.

The Suzuki J18 engine features an aluminum cylinder block and aluminum cylinder head with two overhead camshafts (DOHC) and four valves per cylinder (16 in total). Cylinder bore and piston stroke are 84.0 mm (3.31 in) and 83.0 mm (3.27 in), respectively. Compression ratio rating is 9.8:1.

The Suzuki J18 engine is equipped with Multi-point fuel injection and electronic ignition system with individual ignition coil for each spark plug.

The J18 engine produced 121 PS (89 kW; 120 HP) at 6,200 rpm of maximum horsepower and 152 N·m (15.5 kg·m, 112 ft·lb) at 3,400 rpm of peak torque.

The breakdown of the engine code is as follows:

• J – Engine family
• 18 – 1.8 Liter Displacement

General information

Cylinder block

The Suzuki J18 has an aluminum cylinder block with five bearing support system. A cylindrical cast iron sleeve is installed in each cylinder. It has an 84.0 mm (3.31 in) cylinder bore and 83.0 mm (3.27 in) piston stroke. Compression ratio rating is 9.8:1. The piston is cast aluminum alloy and has two compression rings (top and 2nd rings), and one oil ring.

Crankcase bolts tightening procedure and torque specs:
10 mm

• Step 1: 40 Nm; 4.0 kg·m; 29.0 ft·lb
• Step 2: 0 Nm; 0 kg·m; 0 ft·lb
• Step 3: 40 Nm; 4.0 kg·m; 29.0 ft·lb
• Step 4: 58 Nm; 4.8 kg·m; 42.0 ft·lb

8 mm

• Step 1: 26 Nm; 2.6 kg·m; 19.0 ft·lb

After securing bearing cap bolts, make sure crankshaft turns smoothly by hand.

Connecting rod bearing bolts

• Step 1: 45 Nm; 4.5 kg·m; 33 ft·lb

Cylinder head

The cylinder head is made of aluminum alloy which gives it good cooling efficiency. The combustion chamber is pent roof type and a spark plug is positioned in the center of the combustion chamber and between intake ports and exhaust ports. The engine has dual overhead camshaft design with four valves per cylinder. The double overhead camshaft is mounted over the cylinder head; it is driven from the crankshaft through timing chains, and no pushrods are provided in the valve train system. Intake valves are 33.0 mm (1.2992 in) in diameter, and the exhaust valves are 28.0 mm (1.1024 in).

The Suzuki J18 used hydraulic valve lash adjusters. The hydraulic valve lash adjuster, located between the camshaft and valve stem, is direct-acting type. With the engine oil delivered into it from the oil pump, the adjuster operates as follows so as to adjust the valve lash (clearance) to “zero” automatically at all time.

Head tightening procedure and torque specs:
For M6 bolts:

• Step 1: 11 Nm (1.1 kg·m, 8.0 ft·lb)

For M10 bolts:

• Step 1: 53 Nm; 5.3 kg·m; 38.5 ft·lb
• Step 2: 84 Nm; 8.4 kg·m; 61.0 ft·lb
• Step 3: Loosen all bolts to 0 Nm; 0 kg·m; 0 ft·lb
• Step 4: 53 Nm; 5.3 kg·m; 38.5 ft·lb
• Step 5: 105 Nm; 10.5 kg·m; 76.0 ft·lb

Maintenance data

Vehicle applications

Author: Sergei Wers
About: Co-founder and CEO of a multi-brand auto repair shop (engine repair, chassis repair, body repair and painting) for over 15 years. I have been developing internet sites with technical specifications for more than seven years.