Parked tractor on Thursday. Went to use it on Saturday. Mashed clutch, fired her off and startied putting shuttle shift into gear. Tractor acted like no clutch engagement. Clutch worked fine on Thursday. Inherited tractor. When I got it, it had 385 hours. Now has 1177. It has never fully shifted into the low side of the shift lever. But has always stayed engaged. What would cause the clutch to stop working sitting for 2 days? 2017 yr model. L4701