1986 John Deere 650 Tractor Engine Removal

With the loader out of the way, I moved forward with taking out the engine. The first step in engine removal is to remove the front frame and axle. Of course it is. Ok, so the reason is because the engine block is an integral part of the tractor frame. The front frame bolts directly to the engine block, and the engine block is bolted to the clutch housing.

To get the frame disconnected, I first needed to remove the rear support for the loader (another "of course"). The steering arm drag link needed to come free of the front steering knuckle, and wiring for lights (of which there currently aren't any) also needed to be fished out, then seven bolts are removed. I supported the rear half of the tractor with a jack stand, then used a floor jack to balance the front end and roll it away.

A lot more unhooking or removal of stuff, and the engine with clutch came free of the rear end of the tractor. The engine is sitting on a Harbor Freight motorcycle jack. That thing really comes in handy for a lot of uses other than motorcycles.

The below photo shows the clutch and flywheel removed from the engine.

The reason for doing all this work (engine removal) is to figure out why the clutch stopped working. I heard a pop inside the clutch housing when I pushed the clutch pedal down while adjusting the clutch pedal free play, and I made an assumption that a couple of roll pins had sheared off in the throw-out bearing yoke (items 2 and 3 in the illustration below). I can't really tell if they have sheared off but they look pretty normal. If they are sheared off, it'll be a bear to get the pieces out, as roll pins are hardened steel and don't take kindly to drilling..

I'm wondering if maybe the throw-out bearing (6) somehow slid rearward on the sleeve (9) shown in the illustration below, and maybe that was the "pop" I'd heard earlier. It seems to be in good condition, as it spins very smoothly. In any event, I'll be getting a new throw-out bearing and clutch disc, since it's such a huge job to replace those things in this tractor.

One other issue I was having prior to the clutch giving out was that when I pushed in the clutch, the transmission input shaft would continue spinning, causing grinding when shifting into gear. I'm hoping to solve that issue with a new clutch disk.