LEMON Manuals: Even more car manuals for everyone
Home >> Mercury >> 2002 >> Cougar 2.5 L, Automatic >> Repair and Diagnosis >> Engine Mechanical >> Mechanical >> Engine System-General Information >> Specifications >> General Specifications - 2.5L

General Specifications - 2.5L

GENERAL SPECIFICATIONS - 2.5L

Item Specification
Displacement 2.5L (153 CID)
Number of cylinders 6
Bore and stroke 82.4 x 79.5
Firing order 1-4-2-5-3-6
Oil pressure (hot 1500 RPM) 138--310 kPa (20--45 psi)
Cylinder head and valve train 
Combustion chamber volume 44.5 +/-1.5 cc
Valve seats - width intake 1.1--1.4 mm
Width exhaust 1.4--1.7 mm
Angle 44.75 degrees
Runout (T.I.R.) max 0.04 mm
Valve stem to guide clearance intake 0.020--0.069 mm
Valve stem to guide clearance exhaust 0.045--0.094 mm
Valve head diameter intake 32 mm
Valve head diameter exhaust 26 mm
Gauge diameters 31 and 24.5 mm
Valve face runout limit 0.05 mm
Valve face angle 45.5 degrees
Valve stem diameter (STD) intake 5.975--5.995 mm
Valve stem diameter (STD) exhaust 5.950--5.970 mm
Valve springs compression pressure (N @ spec length) intake 680 N @ 30.19 mm
Valve springs compression pressure (N @ spec length) exhaust 680 N @ 30.19 mm
Free length (approximate) intake 46.8 mm
Free length (approximate) exhaust 46.8 mm
Installed pressure (N @ spec length) intake 228 N @ 39.99 mm
Installed pressure (N @ spec length) exhaust 228 N @ 39.99 mm
Service limit 10% Pressure Loss @ 30.09
Out of square limit 1%
Rocker arm ratio 1.8:1
Hydraulic valve tappet diameter (STD) 16-15.988 mm
Clearance to bore 0.018--0.069 mm
Service limit 0.016 mm
Hydraulic leakdown rate 5--25 seconds
Collapsed valve tappet gap - desired 0.50--1.11 mm
Camshaft 
Lobe lift  
Intake (primary) 4.79 mm
Intake (secondary) 4.79 mm
Exhaust 4.79 mm
Allowable lobe lift loss 0 mm
Theoretical valve lift @ zero lash
Intake (primary) 9.80 mm
Intake (secondary) 9.80 mm
Exhaust 9.80 mm
End play  
Standard 0.025--0.165 mm
Service limit 0.190 mm
Journal to bearing clearance
Standard 0.025--0.076 mm
Service limit 0.121 mm
Journal diameter (all) 26.926--26.936 mm
Bearing inside diameter (all) 27.012--26.897 mm
Cylinder block 
Head gasket surface
Head gasket surface flatness-cylinder block 0.025 / 25 x 25.050/ 150 x 150
Head gasket surface flatness-cylinder head 0.025 / 25 x 25.050/ 150 x 150
Head gasket surface flatness-cylinder block 0.025 / 25 x 25.050/ 150 x 150
Head gasket surface finish -flatness-cylinder head 0.025 / 25 x 25.050/ 150 x 150
Main bearing bore diameter 68.998--69.022 mm
Cylinder bore - Diameter Grade 1: 82.4--82.410 mm grade 2: 82.411--82.421 mm grade 3: 82.420--82.430 mm
Surface finish (RMS) 0.2--0.6 microns
Out-of-round limit 0.015 mm
Out-of-round service limit 0.020 mm
Taper service limit 0.006 mm
Crankshaft 
Main bearing journal diameter 62.968--62.992 mm
Connecting rod journal diameter 49.970--49.990 mm
Crankshaft free play 0.110--0.232 mm
Crankshaft runout to rear face of cylinder block 0.050 mm max
Connecting rod bearings
Clearance to crankshaft 0.028--0.066 mm
Bearing wall thickness (STD) 0.250 mm undersize - add 0.125 mm to standard or grade 2 thickness 1.503
Main bearings - Clearance to crankshaft-desired 0.025--0.045 mm
Main bearings - Clearance to crankshaft-allowable 0.025--0.050 mm
Main bearings - Bearing wall thickness - grade 1 2.501 mm
Main bearings - Bearing wall thickness - grade 2 2.505 mm
Main bearings - Bearing wall thickness - grade 3 2.510 mm
Connecting rod 
Piston pin bore diameter 21.071--21.032 mm
Length (center to center) 138.06--138.4 mm
Alignment (bore to bore max difference) Pin bore and crankshaft bearing bore must be parallel and in same vertical plane within the specified total difference when measured at the ends of a 203 mm bar, 101.5 mm on each side of the centerline
Twist 0.050 mm per 25
Band 0.038 mm per 25
Side clearance (assembled to crank) - Standard 0.100-0.30 mm
Side clearance (assembled to crank) - Service limit 0.35 mm max.
Pistons 
Diameter Measured at 43 mm from outer perimeter top of piston to the pin axis
Coded grade 1 82.390--82.410 mm
Coded grade 2 82.398--82.442 mm
Coded grade 3 82.410--82.430 mm
Piston to bore clearance 0.012 to 0.022 mm
Pin bore diameter 21.008--21.012 mm
Ring groove width -
Compression (top) -
Compression (bottom) -
Oil ring 3.030--3.055 mm
Piston pin - Length 55.05--55.47 mm
Piston pin - Diameter 21.011--21.013 mm
Pin to piston clearance -0.005 to +0.001 mm
Pin to rod clearance - Standard 0.004--0.020 mm
Pin to rod clearance - Service limit 0.035 mm
Side clearance -
Compression (top) 0.040--0.075 mm
Compression (bottom) 0.040--0.085 mm
Oil ring Snug fit
Service limit 0.10 mm
Piston ring gap Specification 82.4 mm diameter gauge
Compression (top) - gauge diameter 0.100--0.250 mm
Compression (bottom) - gauge diameter 0.27--0.42 mm
Oil Ring (steel rail) - gauge diameter 0.15--0.65 mm
Compression (top) service limit 0.50 mm max
Compression (bottom) - service limit 0.65 mm max
Oil ring (steel rail) - service limit 0.90 mm max
Lubrication system 
Oil capacity with filter change 5.5 liter
Drive belt tension 
NOTE: Belts have differing tension specifications depending on whether they are new installed or used
Automatic tensioners
6 Rib front end accessory drive (FEAD)-Water pump belt Automatic tensioners
3 Rib rear end accessory drive (READ)-Water pump belt No adjustment required