Maybe try cleaning it out? I assume when you say "clutch" you mean the blade clutch, not the self propelled drive which is what uses the belt. There are a few components to the blade clutch. It's been a long time since I had mine apart, but these are the points I recall.
First - make sure all the bolts are tight. If they are not things will not act properly.
1) When idling with the blade disengaged there is a bearing that the engine is allowed to spin in. Symptoms of this being bad are howling bearings with the blade disengaged.
2) When idling with the blade disengaged there is a friction material designed to drag the blades down and ensure the blades stop quickly in the event of an emergency / you let go of the handles. This friction material COULD be still be dragging even after it should be disengaged. I recall there was some sort of spring / flex plate type assembly in there that helped control when / where everything came together and when it moved apart. If that was all jammed up with gunk it maybe it could cause drag.
3) When the blade is engaged the blade matches the engine speed. There is another friction surface in there that controls this engagement. You may want to try SLOWLY engaging the blades to see if you may just have a timing issue / where it's being pulled too quickly.
4) There is another bearing that should be checked... I can't recall exactly what condition that one spins under, but it MIGHT only be when the blade is engaged, in which case if that was bad it could cause problems too.
First - make sure all the bolts are tight. If they are not things will not act properly.
1) When idling with the blade disengaged there is a bearing that the engine is allowed to spin in. Symptoms of this being bad are howling bearings with the blade disengaged.
2) When idling with the blade disengaged there is a friction material designed to drag the blades down and ensure the blades stop quickly in the event of an emergency / you let go of the handles. This friction material COULD be still be dragging even after it should be disengaged. I recall there was some sort of spring / flex plate type assembly in there that helped control when / where everything came together and when it moved apart. If that was all jammed up with gunk it maybe it could cause drag.
3) When the blade is engaged the blade matches the engine speed. There is another friction surface in there that controls this engagement. You may want to try SLOWLY engaging the blades to see if you may just have a timing issue / where it's being pulled too quickly.
4) There is another bearing that should be checked... I can't recall exactly what condition that one spins under, but it MIGHT only be when the blade is engaged, in which case if that was bad it could cause problems too.
