Regardless, you need to swap out those electrolytic capacitors as soon as possible. They have definitely leaked and that leaked fluid is slowly chewing on your board. I speak from firsthand experience as a fellow Mac 512k owner on this. It's much easier to swap caps on a 128k/512k board than doing the same on an SE/30, let me tell you!

Here's my 512k board:




You can see the 3 caps that need replacing from looking at my 128k motherboard photos here: