I have a 2005 John Deere Buck 650 4x4 and I'm reading that it's the same engine as the Quest. My bike's solenoid went out about 6 months ago and I just got around to changing it out. When I got it started I noticed there was an oil leak accompanied by a knocking noise. I fixed the oil sensor that was leaking but the knocking noise is still there. When I changed the oil I did notice metal shavings in the oil and on the oil filter. Any idea on what this could be or what I could be looking at to get it fixed? Any help is appreciated.