Clutch Runout
CLUTCH DISCCheck the clutch disc before installation. Axial (face) runout of a new disc should not exceed 0.5 mm (0.020 inch). Measure runout about 6 mm (1/4 inch) from the outer edge of the disc facing. Obtain another disc if runout is excessive.
CLUTCH COVER
Check condition of the clutch cover before installation. A warped cover or diaphragm spring will cause grab and incomplete release or engagement. Be careful when handling the cover and disc. Impact can distort the cover, diaphragm spring, release fingers and the hub of the clutch disc.
Use an alignment tool when positioning the disc on the flywheel. The tool prevents accidental misalignment which could result in cover distortion and disc damage.
A frequent cause of clutch cover distortion is improper bolt tightening. To avoid warping the cover, the bolts must be tightened in a diagonal pattern and only 2-3 threads at a time to the specified torque.
FLYWHEEL
Flywheel runout should not exceed 0.08 mm (0.003 inch). Measure runout at the outer edge of the flywheel face with a dial indicator. Mount the indicator on a stud installed in place of one of the clutch housing bolts.
Common causes of runout are:
- heat warpage.
- improper machining.
- incorrect bolt tightening.
- improper seating on crankshaft flange shoulder.
- foreign material on crankshaft flange.
Flywheel machining is not recommended. The flywheel clutch surface is machined to a unique contour and machining will negate this feature. However, minor flywheel scoring can be cleaned up by hand with 180 grit emery, or with surface grinding equipment. Remove only enough material to reduce scoring (approximately 0.001 - 0.003 inch). Heavy stock removal is not recommended. Replace the flywheel if scoring is severe and deeper than 0.076 mm (0.003 inch). Excessive stock removal can result in flywheel cracking or warpage after installation; it can also weaken the flywheel and interfere with proper clutch release.
Clean the crankshaft flange before mounting the flywheel. Dirt and grease on the flange surface may cock the flywheel causing excessive runout. Use new bolts when remounting a flywheel and secure the bolts with MOPAR Lock And Seal. Tighten flywheel bolts to specified torque only. Overtightening can distort the flywheel hub causing runout.