I posted this in another thread but thought it might help others searching the threads....
If you think that you may have spun a beering: must read
Funny how some can hear a spun beering over the internet.
The first test is to test your oil:
Drain the oil and filter into a clean mortar pan. Then while the drain plug is still off pour in a quart or two of warm low weight ~5W30 motor oil to push the residue out of the pan. Then look for silvery stains on top of the old oil caused by the beerings. Using a funnel, magnet and a coffee filter. Place the filter into the funnel then the magnet. Pour the oil through the filter. It will grab all of the beering material if there is any.
Next; repace the oil and filter. Start the engine and track the noise down using a stethiscope if advalible.
Once you narrow it down to the closest cylinders:
Starting with the closest cylinder, pull the spark plug wire (ground it) and restart the engine. The noise should have drastically changed. If the knock didn't then repeat the test with the surrounding cylinders until you find the correct cylinder.
The reason for the knock to diminish is because by not firing that cylinder you have taken away the force causing the knock.
Using a helper to start and start the engine, this test should only take a couple of minutes.
Many use an old plug wire w/ the plug side cut off and stripped back and grounded to the engine (Aligator clips speer this up). Then w/ eng off pull the plug wire at the dizzy and install the grounded one. Start the engine till you hear or don't hear the knock, then kill the engine. If knock sounds the same, then go to the next cylinder plug wire and retest....
This test should only take ~15 minutes or so.
1.For ease of writing this please realize that more than one cylinder may have beering woes and the knock sound may only change as one of the affected cylinders plug wire is disconnected.
2. As for being able to accurately diagnois a spun beering over the internet, others may, but my hearing just isn't that good.