A related question:

Could a rear heater core leak also be the source of air getting into the system?

My '87 is currently suffering from sporadic overheating, despite being bled
properly, and I suspect that there is trapped air in the system and that it may
be due to a heater core leak or simply that the system won't hold correct
pressure because of the leak, causing a boil-over.

While there are no external leaks, I do also sense the familiar "maple syrup"
smell as I'm driving, so I'm wondering if this is MY problem as well.

Looking for opinions,

Dan