Nissan 100NX N14 silhouetteN14

Cylinder Head - Inspection (Valve Dimensions, Springs, Lifter)

EM-222prose procedure

CD17 uses mechanical valve lifter; CD20 uses hydraulic valve lifter.

Continued from EM-221

CYLINDER HEAD — Inspection

Valve Dimensions

  1. 1
    Check dimensions of each valve. For dimensions, refer to S.D.S.
    Valve dimension diagram with callouts: T (margin thickness), face angle α, head diameter D, stem diameter d, and overall valve length L.
    SEM188A
  2. 2
    Correct or replace any valve that is faulty.
  3. 3
    Valve face or valve stem end surface should be refaced by using a valve grinder.
    When valve head has been worn down to 0.5 mm (0.020 in) in margin thickness, replace the valve.
    Grinding allowance for valve stem tip is 0.5 mm (0.020 in) or less.
    Valve grinder refacing a valve face / valve stem end surface.
    EM111

VALVE SPRING SQUARENESS

Check valve spring for squareness using a steel square and flat surface plate. If spring is out of square "S" more than specified limit, replace with new one.
Out-of-square, Outer0.083 in
Less than 2.1mm
Out-of-square, Inner0.075 in
Less than 1.9mm

VALVE SPRING PRESSURE LOAD

Measure the free length and the tension of each spring. If the measured value exceeds the specified limit, replace spring. Refer to S.D.S.

VALVE LIFTER

Valve Lifter

  1. 1
    Check contact and sliding surfaces for wear or scratches.
    Valve lifter shown with arrows indicating the contact and sliding surfaces to inspect for wear or scratches.
    SEM723B
Support our work!

See also

S.D.S.

Search Manual

Search pages, specs, and procedures