1982 KZ440-D Belt LTD metal in oil pan and screen

Well I just bought a beat up 1981 for $800 with a real smooth motor and tranny in case I need a motor. Has all original parts, so it is a good parts bike that I will restore also. My current motor in the 1982 runs great, but I do notice that the grinding noise is affected by my pulling in the clutch. I guess I may have a clutch going? Is there aluminum in the clutch that could break up? Maybe one of the side supports that hold the plates in? Anyone ever see or hear their clutch go to pieces?!