tbran
Guest
we have had this before. Found two things. 1 the main drive belt has lost the cord tensile strength and is stretching under load. This allows the idler to come in and release the snubber and through vibration it gets thrown off. 2. Not enough tension on the idler spring. Some of the springs are stronger than others we found. We have replaced stock unit with a drawbolt unit (requres welding a bracket to accept drawbolt) off a M2_l2. It is also assumed your idler is not loose in the pivot area allowing a idler vibration effect. Finally we had a customer replace the rubber snubber with a shock as on the wobble box drive . These are the fixes. Really strange why some machines had this problem and others not and why more on F3's than F2's. Same setup. Go figure.