Nissan RD28

The Nissan RD28 is a 2.8 l (2,826 cc, 172.44 cu-in) straight six, water-cooled naturally aspirated diesel engine from Nissan RD-family, manufactured by the Nissan Motor Company since 1985 to 1999.

The RD28 has a cast-iron cylinder block, an aluminum cylinder head with SOHC (Single overhead camshaft) and two valves per cylinder. The Nissan RD28 compression ratio is 21.2:1. Cylinder bore and piston stroke are 85.0 mm (3.35 in) and 83.0 mm (3.27 in), respectively.

The early engine versions produced 94 PS (69 kW, 93 HP) at 4,800 rpm and 177 Nm (18.0 kg·m; 130.6 ft·lb) at 2,400 rpm; the later versions produced 100 PS (73 kW; 98 HP) at 4,800 rpm of horsepower and 178 Nm (18.2 kg·m; 131.2 ft·lb) at 2,400 rpm or of torque.

The breakdown of the engine code is as follows:

• RD – Engine Family
• 28 – 2.8 Liter Displacement

General information

Cylinder block

The RD28 cylinder block has a monoblock high-strength cast iron structure and seven-bearing-support system. The engine has a drop-forged steel crankshaft with balance weights. The RD28 motor has two compression and single oil control ring. The cylinder bore is 85.0 mm (3.35 in), piston stroke is 83.0 mm (3.27 in) and compression ratio rating is 21.2:1. The connecting rod’s length is 140.0 mm (5.512 in), the crankshaft journal diameter is 54.0 mm (2.13 in) and crankpin diameter is 50.0 mm (1.97 in).

Main bearing cap bolts tightening procedure and torque specs:

• 69-78 Nm; 7.0-8.0 kg·m; 51-58 ft·lb

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

Connecting rod bearing cup bolt

• Step 1: 14-16 Nm; 1.4-1.6 kg·m; 10-12 ft·lb
• Step 2: 37-45 Nm; 3.8-4.6 kg·m; 27-33 ft·lb

Crankshaft pulley bolt

• 142-152 Nm; 14.5-15.5 kg·m; 105-112 ft·lb

Flywheel fixing bolts

• 137-157 Nm; 14.0-16.0 kg·m; 101-116 ft·lb

Cylinder head

The RD28 has a one-piece aluminum cylinder head with single overhead camshaft and two valves per cylinder: one intake and exhaust made of special heat-resistant steel. The camshaft is driven by a timing belt from the crankshaft. Intake valves are 39.0 mm (1.54) in diameter, and the exhaust valves are 32.0 mm (1.26 in).

The early Nissan RD28 engines were equipped with valve shims for adjusting the valve clearance, the later versions used self-adjusting hydraulic tappets.

Head tightening procedure and torque specs:
M12 bolt

• Step 1: 29 Nm; 3.0 kg·m; 22 ft·lb
• Step 2: 113 Nm; 11.5 kg·m; 83 ft·lb
• Step 3: Loosen all bolts completely
• Step 4: 29 Nm; 3.0 kg·m; 22 ft·lb
• Step 4: 118-127 Nm; 12.0-13.0 kg·m; 87-94 ft·lb or turn all bolts 100-105°

Crankshaft gear bolt

• 123-132 Nm; 12.5-13.5 kg·m; 90-98 ft·lb

Maintenance data

Vehicle applications

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