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Home >> Jeep >> 1998 >> Cherokee 2WD L4-150 2.5L VIN P MFI >> Repair and Diagnosis >> Specifications >> Mechanical Specifications >> Engine >> Cylinder Head Assembly >> Valve, Intake/Exhaust
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Valve, Intake/Exhaust

Valve Lift
Exhaust 10.528mm (0.4145inch)
Intake 10.350mm (0.4075inch)

Intake Valve Timing
Opens 15.4 BTDC
closes 58 ABCD

Exhaust Valve Timing
Opens 52.8 BBDC
Closes 26.2 ATDCValve Overlap 41.6
Intake Duration 253.3
Exhaust Duration 259


Valves
Length (tip-to-Gauge
Dimension Line) Intake 124.435 to 125.070mm (4.899 to 4.924inch)
Length (tip-to-Gauge
Dimension line) Exhaust 125.120 to 125.755mm (4.927 to 4.952inch)
Valve Stem Diameter 7.899 to 7.925mm (0.311 to 0.312 inch)
Stem-to-Guide Clearance 0.025 to 0.076mm (0.001 to 0.003 inch)
Valve Head Diameter-
Intake 48.387 to 48.641mm (1.905 to 1.915 inch)
Valve Head Diameter-
Exhaust 37.973 to 38.227mm (1.495 to1.05 inch)
Valve Face Angle-Intake 45
Valve Face Angle-Exhaust 45
Tip Refinishing (Max. Allowable) 0.25mm (0.010 inch)
Valve Springs
Free Length (Approx.) 47.65mm (1.876 inch)
Spring Tension-
Valve Closed 271 to 307 N 41.656mm (61 to69 lbf. 1.64)
Spring Tension-
Valve Open 818.5 to 871.9 N 30.89mm (184 to 196 lbf 1.216 inch)
Inside Diameter 21.0mm to 21.51mm (0.827 to 0.847 inch)
Installed Height 41.656mm (1.640 inch)Pistons
Weight (Less Pinch) 563 to 567 grams (19.86 to 20.00 oz.)
Piston Pin Bore
(Center to Piston Top) 40.61 to 40.72mm (1.599 to 1.603 inch)
Piston-to-Bore Clearance 0.033 to 0.053mm (0.0013 to 0.0021 inch)
Piston-to-Bore Clearance
(Preferred) 0.033 to 0.038mm (0.0013 to 0.0015 inch)
Piston Ring Groove Height-
Compression Rings 1.530 to 1.555mm (0.0602 to 0.0612 inch)
Piston Ring Groove Height-
Oil Control Ring 4.035 to 4.060mm (0.1589 to 0.01598 inch)
Piston Ring Groove Diameter-
Compression Rings 87.78 to 87.90mm (3.456 to 3.461 inch)
Piston Ring Groove Diameter-
Oil Control Ring 87.50 87.75mm (3.445 to 3.455 inch)
Piston Pin Bore Diameter 23.647 to 23.655mm (0.9310 to 0.9313 inch)
Piston Pin Diameter 23.637 to 23.640mm (0.9306 to 0.9307 inch)
Piston-to-Pin Clearance 0.0076 to 0.0178mm (0.0003 to 0.0007 inch)
Piston-to-Pin Clearance
(Preferred) 0.015mm-Loose (0.0006 inch-Loose)
Piston-to-Pin Connecting Rod
(Press Fit) 8.9 kN (2000 lbf.)
Piston Rings
Ring Gap Clearance-
Top Compression Ring 0.229 to 0.610mm (0.0090 to 0.0240 inch)
Ring Gap Clearance-
2nd Compression Ring 0.483 to 0.965mm (0.0190 to 0.0380)
Ring Gap Clearance-
Oil Control Steel Rails 0.254 to 1.500mm (0.010 to 0.060 inch)
Ring Side Clearance-
Compression Rings 0.042 to 0.084mm (0.0017 to 0.0033 inch)
Ring Side Clearance-
Oil Control Ring 0.06 to 0.21mm (0.0024 to 0.0083 inch)
OilPump
Gear-to-Body Clearance
(Radial) 0.051 to 0.102mm (0.002 to 0.004 inch)
Gear-to-Body Clearance
(Radial) (Preferred) 0.051mm (0.002 inch)
Gear End Clearance-
Plastigage 0.051 to 0.152mm (0.002 to 0.006 inch)
Gear End Clearance-
Plastigage (Preferred) 0.051mm (0.002 inch)
Gear End Clearance-
Feeler Gauge 0.1016 to 0.2032mm (0.004 to 0.008 inch)
Gear End Cearance-Feeler
Gauge (Preferred) 0.1778mm (0.007 inch)
Oil Pressure
Min. Pressure (600 rpm) 89.6 kPa (13 psi)
At Idle Speed (800 rpm) 172 to 241 kPa(25 to 35 psi)
At 1600 rpm & Higher 255 to 517 kPa (37 to 75 psi)
Oil Pressure Relief 517 kPa (75 psi)
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