Re: Low oil pressure
well, its not looking good. I am assuming that the original engine had a bearing take a dump, and thats why you rebuilt it. If that is true it sent alot of metal into the oil, and respective oiling system. This would include your motor, your turbo, turbo oil lines, oil filter lines, and your factory oil cooler (radiator). You HAVE to replace the radiator, or do what I did and eliminate it with a remote filter that has no cooler lines. For all of those other places, if you didn't clean them out then they are still harboring that original engine oil, which is still full of metal. That metal is back in your engine and tearing your bearings apart (most likly).
From what I understand having the oil analyzed with only 200 miles on it won't work well, they will jsut say "they're are high amouts of copper and bronze and other metals that suggest that you may have a bearing going out, but it might also be part of the natural process of breaking in a motor, we typically cannot be sure unless the motor is fully broken in" Find out if its knocking from inside the motor, take the accessory belt off and listion to it, I even unbolted my torque converter and pushed it back into the trans to make sure I was ONLY hearing the engine, make sure its not exhaust or soemthing of the like. Engine noises tend to make themselves very known.
Did you do this yourself?, if not and shop did this, you could try an get them for not taking proper action with the radiator replacement, and they would be obligated to help you with this problem. If you did it yourself, then your gonna have to pull it back out. If you catch it early enough you might be able to walk away with just a set of bearings and gaskets, prolly a crank grind as well...
I had a huge issue with my engine where I had a torque converter baloon and take out my thrust bearing, 2 weeks after I rebuilt it. It was making all kinds of stupid noise because the crankshaft was walking in and out of the motor. i pulled it out and everything was still savible, the bearings were all bad, but the only machine work I needed done was a crank grind. I hope your not any worse off than that.
This kind of thing really sucks, and I feel bad for you. To have that much work add up to nothing other than a hole burned in your pocket. Don't give up, if you had it out once you can do it again. You shouldn't need a set of rings but check everything out. Put up a build thread and let everyone know whats going on, people check those things, and they are willing to help you out if your not sure of what to do. If you need any advice, let me know.