The PB140 is probably easily fixed. The 1xx series PBs are infamous for somewhat flaky LCD connector behavior. Often, it suffices simply to pull out the flex cable, and then reinsert it. The connector that usually causes this problem is in the lid, not in the base, so you'll need to undo the screws that hold the lid halves together.
The HD is a different matter, of course, but first things first. Get the display working stably, and then you'll be able to see what's going on. Then get yourself a good boot floppy and see if the HD is salvageable with a good reformat.
As for the Newton's clock problem, it may have been dropped at some point, cracking the quartz crystal used by the clock. Cracked crystals oscillate faster than nominal, causing the clocks to run fast, just as in your case. I've never popped open a Newton, so I don't know if this is a good theory. If you do open it up, look for a crystal marked with the digits 32768 (or a subset/rounded version of same). Most (but not all) clocks use a 32.768kHz crystal (because that's the 15th power of 2, making it easy to get a pulse per second by using a chain of 15 dividers), so if you see one, that might be the culprit. The good news is that if you do see one, it's easily replaced by one scavenged from almost every other computer motherboard and wristwatch on the planet.
I agree that the AC vs. battery issue is easily solved, so a little work should get it up and running on both power sources.
The HD is a different matter, of course, but first things first. Get the display working stably, and then you'll be able to see what's going on. Then get yourself a good boot floppy and see if the HD is salvageable with a good reformat.
As for the Newton's clock problem, it may have been dropped at some point, cracking the quartz crystal used by the clock. Cracked crystals oscillate faster than nominal, causing the clocks to run fast, just as in your case. I've never popped open a Newton, so I don't know if this is a good theory. If you do open it up, look for a crystal marked with the digits 32768 (or a subset/rounded version of same). Most (but not all) clocks use a 32.768kHz crystal (because that's the 15th power of 2, making it easy to get a pulse per second by using a chain of 15 dividers), so if you see one, that might be the culprit. The good news is that if you do see one, it's easily replaced by one scavenged from almost every other computer motherboard and wristwatch on the planet.
I agree that the AC vs. battery issue is easily solved, so a little work should get it up and running on both power sources.