Make sure the tranny and engine seals are not leaking, resurface the
flywheel, and put in a new throwout bearing and pressure plate along
with the new disk if he didn't last time.  If he did, he should break
any glaze on the pressure plate with fine emery cloth before
reinstalling it.

It is not a spring problem but a surface problem. Heat will coke up any
small amounts of oil that get on the clutch and cause chatter.  A warped
clutch plate or flywheel can too.  Be sure he uses quality German parts
this time, some of the South American clutches can be problematic.
--
Stuart MacMillan
Manager, Case Program
800-909-8244 ext. 8208

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