It is the same as QR20DE, but new crankshaft with 100.0 mm (3.94 in.) of piston stroke gave the engine a 2.5 L of displacement. The QR25DE engine has an aluminum cylinder block and head. It used dual overhead camshaft (DOHC), four-valve designs with continuously variable valve timing (CVTC) on the intake camshaft, individual ignition coils, electronic throttle, and multi-point fuel injection system. The engine built with cast steel connecting rods, a steel timing chain, counter-rotating balance shafts, and an aluminum intake manifold.
In 2007 the QR25DE was upgraded. The new engine has higher rev limit and improved power output. These upgrade included:
- A larger diameter single path resin intake manifold.
- Revised piston crown shape to support a higher compression ratio of 9.6:1 and up to 10.5:1 in Sentra SE-R Spec V.
- The balancer shafts system has been moved back from the crank pulley to a more centric location.
- Redeisgned camshaft profile.
- Reinforced connecting rods.
- Additional engine mount on the top of the motor, pulley side.
An 89.0 mm (3.504 in) cylinder bore and 100.0 mm (3.94 in) piston stroke give the engine a total of 2.5 L of displacement. Compression ratio rating is ranging from 9.5:1 to 10.5:1 depending on the vehicle. The Nissan QR25DE produces from 147 PS (108 kW; 145 HP) at 5,600 rpm up to 203 PS (149 kW; 200 HP) at 6,000 rpm of horsepower and from 213 Nm (21.7 kg·m; 157.2 ft·lb) at 4,400 rpm to 245 Nm (25.0 kg·m; 180.8 ft·lb) at 4,000 rpm of torque.
The breakdown of the engine code is as follows:
- QR – Engine Family
- 25 – 2.5 Liter Displacement
- D – DOHC (Dual Overhead Camshafts)
- E – Multi Point Fuel Injection
|Layout||Four stroke, Inline-4 (Straight-4)|
|Displacement||2.5 L, 2,488 cc (151.82 cu in)|
|Fuel system||Multi Point Fuel Injection|
147 PS (108 KW; 145 HP) at 5,600 rpm|
160 PS (118 KW; 159 HP) at 5,600 rpm
163 PS (120 KW; 161 HP) at 5,200 rpm
165 PS (121 KW; 162 HP) at 6,000 rpm
167 PS (123 KW; 165 HP) at 5,600 rpm
169 PS (124 KW; 166 HP) at 6,000 rpm
170 PS (125 KW; 168 HP) at 5,600 rpm
170 PS (125 KW; 168 HP) at 6,000 rpm
171 PS (126 KW; 169 HP) at 6,000 rpm
173 PS (127 KW; 170 HP) at 6,000 rpm
179 PS (132 KW; 177 HP) at 6,000 rpm
182 PS (134 KW; 180 HP) at 6,000 rpm
185 PS (136 KW; 182 HP) at 6,000 rpm
203 PS (149 KW; 200 HP) at 6,000 rpm
213 Nm (21.7 kg·m; 157.2 ft·lb) at 4,400 rpm|
230 Nm (23.5 kg·m; 169.7 ft·lb) at 4,400 rpm
230 Nm (23.5 kg·m; 169.7 ft·lb) at 4,000 rpm
233 Nm (23.8 kg·m; 171.9 ft·lb) at 4,000 rpm
233 Nm (23.8 kg·m; 171.9 ft·lb) at 4,400 rpm
234 Nm (23.9 kg·m; 172.7 ft·lb) at 4,000 rpm
240 Nm (24.5 kg·m; 177.1 ft·lb) at 4,000 rpm
245 Nm (25.0 kg·m; 180.8 ft·lb) at 3,600 rpm
245 Nm (25.0 kg·m; 180.8 ft·lb) at 3,900 rpm
|Dimensions (L x H x W):||–|
|Weight||330 lbs (150 kg)|
The QR25DE has an aluminum block, cylinder bore is 89.0 mm (3.504 in) and the piston stroke is 100.0 mm (3.94 in), the compression ratio is ranging from 9.5:1 to 10.5:1 depending on the vehicle.
The pistons are each fitted with two compression rings and single oil ring, cast steel connecting rods are 143.0 mm (5.63 in.) long. The crankshaft for QR25DE engine has two balancer shafts and supported by five main bearings. The crankshaft main journal diameter is 54.97 mm (2.164 in) and crankpin diameter is 44.97 mm (1.77 in.)
|Cylinder block alloy||Cast iron|
|Compression ratio:||9.5:1 to 10.5:1|
|Cylinder bore:||89.0 mm (3.50 in)|
|Piston stroke:||100.0 mm (3.94 in)|
|Number of piston rings (compression / oil):||2 / 1|
|Number of main bearings:||5|
|Cylinder inner diameter (standard):||89.010-89.020 mm (3.5043-3.5047 in)|
|Piston skirt diameter (standard):||88.980-88.990 mm (3.5031-3.5035 in)|
|Piston pin outer diameter:||19.989-19.995 mm (0.7870-0.7872 in)|
|Piston ring side clearance:||Top||0.045-0.080 mm (0.0018-0.0031 in)|
|Second||0.030-0.070 mm (0.0012-0.0028 in)|
|Oil||0.065-0.135 mm (0.0026-0.0053 in)|
|Piston ring end gap:||Top||0.21-0.31 mm (0.0083-0.0122 in)|
|Second||0.32-0.47 mm (0.0126-0.0185 in)|
|Oil||0.20-0.60 mm (0.0080-0.0240 in)|
|Connecting rod center distance:||143.00-143.10 mm (5.63-5.63 in)|
|Connectin rod small end inner diameter:||20.000 mm (0.7874 in)|
|Connectin rod big end inner diameter:||48.000 mm (1.8898 in)|
|Crankshaft journal diameter:||54.979-54.978 mm (2.1645-2.1645 in)|
|Crankpin diameter:||44.974-44.973 mm (1.7706-1.7706 in)|
The engine has an aluminum cylinder head with two chain-driven overhead camshafts (four valves per cylinder) and variable valve timing (CVTC) on the intake camshaft. Intake valves are 35.5 mm (1.398 in.) in diameter, intake duration is 244 °, and the exhaust valves are 30.5 mm (1.20 in.), exhaust duration is 224 °.
The QR25DE engine does not have hydraulic lifters, so special valve lifters are used to adjust the valve clearance.
|Cylinder head (Before upgrade specs)|
|Cylinder head alloy||Aluminum|
|Cylinder head height:||129.4 mm (15.09 in.)|
|Valve Arrangement:||DOHC, chain drive|
|Valves:||16 (4 valves per cylinder)|
|Intake/Exhaust duration:||244/224 °|
|Valve head diameter:||INTAKE||35.5-35.8 mm (1.398-1.409 in)|
|EXHAUST||30.5-30.8 mm (1.201-1.213 in)|
|Valve length:||INTAKE||97.16 mm (3.8252 in)|
|EXHAUST||98.82 mm (3.8905 in)|
|Valve stem diameter:||INTAKE||5.965-5.980 mm (0.2348-0.2354 in)|
|EXHAUST||5.955-5.970 mm (0.2344-0.2350 in)||Cam height:||INTAKE||45.665-45.855 mm (1.7722-1.7797 in)|
|EXHAUST||43.975-44.165 mm (1.7313-1.7388 in)|
|Outer camshaft journal diameter:||№1||27.935-27.955 mm (1.0998-1.1006 in)|
|№2-5||23.435-23.455 mm (0.9226-0.9234 in)|
Head tightening procedure and torque specs:
- Step 1: 98.1 Nm; 10 kg·m; 72 ft·lb
- Step 2: Loosen all bolts completely
- Step 3: 39.2 Nm; 4.0 kg·m; 29 ft·lb
- Step 4: Turn all bolts 75°
- Step 5: Turn all bolts 75° again
Problems and malfunctions
The service life of the QR25DE engine is about 120,000 miles of mileage (200,000 km). The valve clearance needs to be adjusted every 60,000 miles of mileage (90,000 km).
Frequent problems and malfunctions:
- Oil leaks from under the cylinder head cover. That problem fixes by installing the new gasket.
- Idle problems, jerking. The problem in the stretched timing chain. A new timing chain will allow you to forget about any issues related to bad timing chain.
- Random misfire. Fuel injectors or throttle body require cleaning.
- High oil consumption. If your oil consumption exceeds 1 qt. per 1500 miles (0,5L per 1000 km), then the piston rings and valve oil seals need to be replaced.
|Valve clearance (HOT)|
|Intake valve||0.32-0.40 mm (0.013-0.016 in)|
|Exhaust valve||0.33-0.41 mm (0.013-0.016 in)|
|Standard||12.8 kg/cm2 (181 psi) / 250 rpm|
|Minimun||10.8 kg/cm2 (154 psi) / 250 rpm|
|Compression differential limit between cylinders||1 kg/cm2 (14 psi) / 250 rpm|
|Oil consumption , L/1000 km (qt. per miles)||up to 0.5 (1 qt. per 1200 miles)|
|Recommended engine oil||5W-30, 10W-30|
|Oil type API||SG, SH, SJ, SL|
|Engine oil capacity (Refill capacity)||
With filter change 4.2 l (4.5 qt.)|
Without filter change 4.0 l (4.25 qt.)
|Oil change interval, km (miles)||5,000-10,000 (3,000-6,000)|
|Oil Pressure, kPa (bar, kg/cm 2, psi)||
Idle speed: More than 98 (0.98, 1.0, 14)|
2,000 rpm: More than 294 (2.94, 3.0, 43)
6,000 rpm: More than 392 (3.92, 4.0, 57)
Standard: PLFR5A-11 (NGK, Platinum type)|
Cold: PLFR6A-11 (NGK, Platinum type)
Hot: PLFR4A-11 (NGK, Platinum type)
|Spark plug gap||1.1 mm (0.043 in)|
|Spark plug torque||24.5 N·m (2.5 kg·m; 18 lb·ft)|
Valve clearance adjustment data
Calculate the thickness of new adjusting valve lifter so valve clearance comes within specified values.
R = Thickness of removed valve lifter
N = Thickness of new valve lifter
M = Measured valve clearance
N = R + [M – 0.28 mm (0.011 in)]
N = R + [M – 0.30 mm (0.012 in)]
Valve lifters are available in 26 sizes from 6.96 mm (0.2740 in) to 7.46 mm (0.2937 in), in steps of 0.02 mm (0.0008 in).
Example (intake valve):
R = 7.10 mm
M = 0.36 mm
N = 7.10 + (0.36 – 0.28) = 7.18 mm, so we need a valve lifter with code 718.
|For adjusting||For checking|
|Intake||0.24-0.32 mm (0.009-0.013 in)||0.32-0.40 mm (0.013-0.016 in)|
|Exhaust||0.26-0.34 mm (0.010-0.013 in)||0.33-0.41 mm (0.013-0.016 in)|
Whenever valve clearances are adjusted to cold specifications, check that the clearances satisfy hot specifications and adjust again if necessary.
|Nissan Serena C24||2001–2005|
|Nissan X-Trail T30||2001–2007|
|Nissan Sentra SE-R & SE-R Spec V||2002–2006|
|Nissan Sentra SE-R & SE-R Spec V||2007–2012|
|Nissan Altima Hybrid||2007–2011|
|Nissan X-Trail T31||2007–|
|Renault Koleos TR25||2007–|
|Nissan X-Trail T32||2013–|
|Nissan Elgrand E52||2010-|