200 inline 6 Mustang piercing squeak and knocking

[DON]

Just a thought and something to check: I had a starter bendex ( nose that goes in to the flex plate)interference with the flex plate. It made a terrible noise- metal to metal.
I should be easy to verify if this is the source and maybe you have eliminated this already

 

[drag-200stang]

The oil pan is very close to the crank, if the pan gets pushed up it will hit. Unlikely but the dip stick, if bent can hit the crank.

 

[Invectivus]

Did you use a double roller timing chain and maybe they jammed the oil slinger on?

 

[awasson]

Alright so an update on the progress. I pulled the engine out replaced the torque converter AND flexplate. I then installed everything and got ready to turn it over. When I turned it over it ran pretty good without a piercing screech or nock. But then it all started again. I tested the oil pump and it pumped oil good. I haven’t tried taking the valve cover off to see the top end working. This problem is persistent and consistent. What do you guys think about bearings (crank and piston) could these be the problem.

Troubleshooting is a checklist and as you tick the boxes, you get to the bottom of the problem.

Is that bell housing and transmission a 2-piece? If so, I'd remove the transmission and torque convertor and run the engine with the bell housing on, so the starter has something to mount to. I did that with my manual 3-speed when I was tracking down some vibrations. It turned out to be 2 problems; the transmission AND separately the pressure plate.

Do you have a working oil pressure gauge? If you don't, you need one. You need to 100% make sure that it isn't oil starvation and there are a lot of ways for an inline 6 to not have adequate oil pressure.

Screeching can be a main bearing if it's starving for oil or it can be the water pump bearings or alternator bearings or power steering pump if it has one. It's unlikely that it's the distributor but it's something rotating. Could be a hung up starter too. Like @Frank says it could be something related to the camshaft installation but you'll need to pull things apart to see.

The alternator and power steering are pretty easy to determine but the water pump might not be. You can remove the belts for a minute to run it and make sure it isn't one of those but don't run it for long of course.

Have you shined a flashlight down the bores? Again. Super rudimentary exam and will stop you in your tracks if you see damage, scuffing or debris.

If it was mine, by now, I'd have it on an engine stand, removed the pan and head to see what's going on. If it's a bearing, you'll need to do something about it one way or another.