It is a very strange noise that comes and goes so I do not think it is a valvetrain issue. I had it towed home and put in the garage and will begin the tear down in the morning. I will check the valvetrain for sure to see if the issue is there. I think I will know more when I get inside. I will update you tomorrow.
Before my engine completely failed, it made a noise very similar to what I hear in the video. The sound would come and go randomly. In fact the night before the engine finally failed, it sounded perfect, but then the very next day the sound was worse than ever and did not go away.
The problem was caused by bearing failure. One of the bearings between the crankshaft and connecting rods would spin in place and block off the flow of oil to that point, causing the noise, then it would spin again and allow oil to flow properly.
Each time it did that it caused more damage.
I removed the valve covers and of course intake and I am looking at motor and visually everything looks ok. The timing chain and all guides look good so I think I have ruled that out as a problem for now. Not sure how to diagnose the issue mentioned above beside just replacing the bearings and see if that makes the issue go away.
Junk yards generally have an idea which motors run well, that's where my motor came from.
Also Craigs list might have something.
The engine I got purrs like new.
Cars that have been rear ended or hit anywhere else near the rear of the vehicle, are generally good choices for engines.
Look at the plugs and the overall care given to the car before the accident.
I'm curious though, have you recently replaced the water pump? If so, did it dump coolant into the motor oil? I've seen at least three cases recently where the oil was milkshaked from the water pump. then had major bearing failure right after that. Even though the oil was replaced in a timely manner and the pump was replaced too.
I'm starting to make the recommendation that engine bearings be replaced if the water pump causes any milkshake.
Sorry to hear that.
Don't just try to throw in a couple of new bearings in it. From everything I read about it when my car had the same problem, it will not last very long.
The surfaces where the bearings go will need to be machined to make the new bearings last.