The 'churning' I heard was actually the left fan inside the system, which I managed to disassemble so I could lubricate the sleeve bearing with a touch of mineral oil - now it's as quiet as ever and works great.
@shdowflare (Brian M) [Somewhat tangential to this guide, but:] wow, do I feel dumb. I’ve replaced 3 sets of fans in my MBP’s lifetime, due to the inevitable noise that arises after 2-3 years of use. Never thought of just trying mineral oil to relube the fans.
The spudger works well for detaching the connector.
Replying to Andrew Optimus Goldberg: Well, yeah, but ifixit is selling the part at the extreme high-end of the price range. Plus, they dont even tell you which Chinese manufacturer they are using, so you can't check it for reliability/problems.
It says "Note: For certain repairs (e.g. hard drive), removing the battery is not necessary but it prevents any accidental shorting of electronics on the motherboard." This is obviously a boilerplate instruction that is not appropriate for a repair guide.
Well, DO you have to remove the battery? IS this one of those repairs where it's "not necessary but prevents accidental shorting"?
Obviously, this instruction is boilerplate text that accompanies almost all the repair guides-- but there shouldn't be boilerplate text there, since this is a specific guide for replacing the Magsafe DC-in jack and not the harddrive.
Personally, I just could NOT wiggle the Power Supply's connector out in such a way I could safely disconnect it, so this "shortcut" guide didn't help all that much.
As it was, I went the traditional route, using the guide that details removal of the Logic Board. Having said that, Don't Panic: there is an intermediate route, because you don't need to remove the Logic Board! You just need to be able to (safely) lift it at the top a few inches to get access to the Power Supply's connectors. I saved 10-15 steps by not removing all the various connectors on the Logic Board that other guide directed you to do.
Followed that guide, I had a working iMac back up and running for $55.00. My old PSU was Apple P/N 614-0378. The replacement via Amazon seems to be a OEM: SADP-185AF. Had the same form factor and input/output voltage parameters though.
iMac Intel 20" EMC 2218: Model A1207
This is a great overview, but you DONT have to remove all the various connectors to the Logic Board. You're not removing the Logic Board! You just need to be able to remove enough to lift it (at the top) a few inches such that you can get access to the Power Supply's connectors (this saves 10+ steps).
The other "shortcut" guide, iMac Intel 20" EMC 2105 and 2118 Power Supply - short cut method avoids removing logic board Replacement, (which says you dont have to remove the Logic Board at all), I didnt find very useful. I simply could not get at that connector the way it described. Just seemed safer to go about it, using this guide, via a limited removal of the Logic Board.
That being said, followed this guide and had a working iMac back up and running for $55.00. My old PSU was Apple P/N 614-0378. The replacement via Amazon seems to be a OEM: SADP-185AF. Had the same form factor and input/output voltage parameters though.
Could this battery's failure be the reason my iMac died and is now completely unresponsive?