Cooling still not great

[shacky]

I cleaned out my radiators - they were a mess - and replaced capacitors on cooling fans - both were bad - and temp still creeping up when not moving. It's still cool here in Rochester so I'm concerned I'm going to have issues when it gets really hot.

Couple questions:

Thinking I need to refill cooling system with pressurized system to make sure there's no air.

And low speed fan kicks in as soon as I turn on A/C. But I'm not sure it's turning on when needed without A/C on. Is that possible? Wondering if there's a separate regulator.

Thanks!!!