hey, if the a/c is disconnected (pump removed), will the secondary (electric) ea82 fan even come on?

I thought only waterpump clutch type fans were used when cars had ac. They all came standard with electric ones.

I could easily have it backwards, but it has a mechanical fan for primary and the electric kicks in when the a/c is on and drags through the evaporator and rad.

 

I don't remember if it has a temp sensor or if it is keyed (armed?) off the a/c being selected ???

 

life needs more mystery wires :-\

There is both a thermoswitch (rt lower radiator) and a relay that is controlled by the a/c system (temp or pressure - I'm not sure which). The thermoswitch and relay are in parallel so that either can activate the fan. So even without the a/c, it should work if maybe you're idling in traffic for long periods on a hot day.

 

Fyi, I have replaced the thermostatic fan w/ electric in 2 EA82s and split the function so that the right fan is controlled by the radiator thermoswitch (as before) and the left (new fan - actually old EA81 thin fan) is controlled by the a/c (or a manual switch - just in case). I estimate this gives me a few miles better gas mileage. Indicator lights for the fans show that between 30 and 65 mph on a 95 degree day, neither fan runs except maybe on a long uphill. Over about 70 (on same day), the engine creates enough heat load to turn on the right fan. My conclusion is that the thermostatic fan mostly wastes energy (although if you only had 1 fan, it would probably be more reliable and be better able to produce high volume - maybe necessary in a truck!).

 

I also did the same with a Jeep Cherokee with the same results - a few mpg better gas milage and the fans pretty much never run except on very hot days or heavy loads.

 

Perhaps this is why many new(er) cars have done away with the thermostatic fans and use dual electrics. Amazing - those auto engineers!

I could easily have it backwards, but it has a mechanical fan for primary and the electric kicks in when the a/c is on and drags through the evaporator and rad.

 

I don't remember if it has a temp sensor or if it is keyed (armed?) off the a/c being selected ???

 

life needs more mystery wires :-\

 

hi,

it will come on with a/c off , if the coolant temp gets high enough to close the switch on the radiator, not overheated. that is the way mine seems to work.

Thank you all. I removed a dubious electrical set up and had put a mechanical fan on to get home. On the way back the question on the a/c fan came to mind. I will re-install one as a potential fail safe. The dual electric fan idea, to save hp for the wheels, is good. Adding some discreet indicator for peace of mind is very very good.

If you are looking to replace the mechanical fan (I hate them from a maintenance standpoint - really hard to work with/around) - I have a few EA81 A/C fans that will fit in front of the water pump on the radiator. EA81's used dual-electric fans like EJ's.

 

GD

Thankk you GD, I may take you up on that. I'll shoot a PM in the next few days.