1)How can I tell if I have air in the radiator or heater core?
2)To remove air/bubbles in the radiator do you turn the car on w/o the rad cap and fill coolant slowly?
3)Also how do I know if my radiator fans are working properly?
4)Is there a way to test/diagnose the radiator fans?
5)Should they be on after a drive?

Get back at me. I plan on checking my cooling system sometime this weekend or next when I change out my tranny fluid. Last coolant flush was 20,xxx miles ago at firestone.

 

1. Intermittent overheating or loss of heat from blower. Sometimes you can hear "noises" in addition to this.
2. Yes, but it's better to use one of these.
3. They'll intermittently activate.
4. DMM
5. My fans are never running after a drive. In fact, my bottom radiator hose is seldom even hot until after I've turned the car off.
The only time my radiator fan ever really comes on is during stop-and-go traffic, or if I'm parked with the engine running. (occasionally in a drive-thru, also)

 

wow, i totally forgot that device existed...it would have been super useful for when i flushed the coolant in my s2000. the car came with non-oem coolant. to get rid of the orange stuff, i did a drain, water fill, drain, water fill, then a honda long life coolant fill. it was a bloody mess because coolant kept burping out of the rad filler hole. one of those funnels would have really helped.

i wish honda sold the long life coolant as non-premix. my car takes about 8L of coolant and it's a pain in the *** getting the correct mixture if i do a water flush first.