replaced old blown engine and the engine we replaced it with sounds like a diesel. this engine had been sitting for at least 1 year off the old car .engine had 121000 miles and had a cracked timing cover where the waterpump sits,engine came from a wrecked car. timing cover was replaced from old engine. i have let it run for a while but does not go away. tried putting 50 weigth oil and the noise was still there, it only settled down a bit but still noisy. no check engine light/no miss fire/idles smooth/spark plugs all new bosch plat 4 but they turned black after 15min of car being on/when oil was drained to put in the 50 weigth, oil filter and oil had small shavings of alumminum/ starts with no problem.. please help:banghead:

hmmmmm You said that the timing cover was cracked, mabe camshaft or crankshaft was pushed in or bent in the accident.

You may want to pull that timing cover and check inside for rub marks. Your timing chain may be loose/stretched. I had the same issue on my M42 engine 3 series, and it was the timing chain hitting the cover. I replaced the chain and tensioner and all is well. Any idea how many miles since it was last changed?