I bought a 87 4x4 22r today and it has a horrible knock or clanging noise. I removed the head cover and didnt see anything unusual. I have removed all the bolts from the oil pan but I cant get the pan out. I think I have to loosen the motor mount bolts and jack up the motor and tranny. Is there anything I should be doing diferent or I should be looking for? I drained all the oil and didnt see any metal shavings or anything. Someone said it could be the timing chain clanking against the cover, if this was true, would the chain have a lot of slack in it, or how could I check it?