Radiator Fan or Switch

[looker44]

81 FI Fan is not coming on. I have measured voltage and get 12 volts at connector also horn works. I jumped connector and fan does not come on. Does this mean fan is out?
My radiator is POS, so I am thinking abut replacing radiator, cap, fan and switch. Hoses are very new.
I see 2 bolts for radiator with some rubber mounts and a bottom rubber mount
I see 3 bolts for fan to radiator
any mechanical / electrical gotchas besides avoid air bubble
do I need to remove anything else other than rad and fan? I have already taken out washed bottle

[courtenay]

It might mean you have an air bubble in the cooling system or your thermostat isn't working. When the engine is warm, is the lower part of the rad cooler than the upper? Is the hose from the bottom of the t-stat to the bottom of the rad cooler than the top hose? The temp sensor for the fan is at the bottom of the rad. If you have an air bubble in the system or a bad t-stat, the water doesn't circulate through the bottom of the rad and the sensor won't activate the fan.

[looker44]

no to air bubble - I jumped connector and fan does not come on.

[vandor]

If you get 12V at the fan then just apply ground to the ground wire and see if the fan comes on. Do it at the fan's connector so you eliminate any possible broken wires/connectors.