Nissan QG15DE

The Nissan QG15DE is a 1.5 liter (1,497 cc, 91.35 cu·in) straight-four 4-stroke natural aspirated gasoline engine from Nissan QG-family.

The QG15DE motor has a cast-iron cylinder block and aluminum alloy cylinder head with two overhead camshafts (DOHC). The engine uses a multi-point fuel injection system; an electronic ignition system with individual ignition coil for each cylinder and ERG system. From 1998 to 2001 on Nissan Sunny, the QG15DE engine was available as a Lean Burn version.

It has a 73.6 mm (2.9 in) cylinder bore and 88.0 mm (3.46 in) piston stroke. The compression ratio rating is 9.9:1. The Nissan QG15DE engine produced from 90 PS (66 kW; 88 HP) at 5,600 rpm to 109 PS (80 kW; 107 HP) at 6,000 rpm of maximum output power and from 128 N·m (13.1 kg·m, 94.3 ft·lb) at 2,800 rpm to 143 N·m (14.6 kg·m, 105.4 ft·lb) at 4,000 rpm of peak torque.

The breakdown of the engine code is as follows:

• QG – Engine Family
• 15 – 1.5 Liter Displacement
• D – DOHC (Dual Overhead Camshafts)
• E – Multi Point Fuel Injection

General information

Cylinder block

The QG15DE motor has a cast-iron cylinder block, cylinder bore is 73.6 mm (2.9 in) and the piston stroke is 88.0 mm (3.46 in). The pistons are each fitted with two compression rings and a single oil ring. The compression ratio is 9.9:1. The engine uses forged-steel connecting rods. The crankshaft main journal diameter is 49.95 mm (1.966 in) and pins journal diameter is 39.97 mm (1.57 in).

Cylinder head

The engine has an aluminum cylinder head with two chain-driven overhead single-piece cast camshafts and sixteen valves (four per cylinder). The QG15DE has a single timing chain. Intake valves are 29.0 mm (1.14 in) in diameter and the exhaust valves are 24.0 mm (0.95).

The QG15DE does not have hydraulic lifters, so special shims are used to adjust the valve clearance.

Head tightening procedure and torque specs:

• Step 1: 29.4 Nm; 3.0 kg·m; 22 ft·lb
• Step 2: 58.8 Nm; 6.0 kg·m; 43 ft·lb
• Step 3: Loosen all bolts completely
• Step 4: 29.4 Nm; 3.0 kg·m; 22 ft·lb
• Step 5: Turn main bolts 50-55° or 58.8 Nm; 6.0 kg·m; 43 ft·lb

Maintenance data

Valve clearance adjustment data

Calculate the thickness of the new adjusting shim so valve clearance comes within specified values.

R = Thickness of removed shim
N = Thickness of new shim
M = Measured valve clearance

Intake:
N = R + [M – 0.37 mm (0.0146 in)]
Exhaust:
N = R + [M – 0.40 mm (0.0157 in)]

Shims are available in 50 sizes from 2.00 mm (0.0787 in) to 2.98 mm (0.1173 in), in steps of 0.02 mm (0.0008 in).

Example (intake valve):
R = 2.10 mm
M = 0.52 mm
N = 2.10 + (0.52 – 0.37) = 2.25 mm, so we need a shim with code 225.

*: At a temperature of approximately 20°C (68°F)

Whenever valve clearances are adjusted to cold specifications, check that the clearances satisfy hot specifications and adjust again if necessary.

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.