Had something bad happen a few days ago: while idling with the a/c on in line for a stop light my Jeep suddenly started to shake violently as the electric fan came on. When I pulled over I found that the fan blade outer ring had cracked and chiped in one place putting the whole thing dangerously off-balance. I seem to remember my friend accidentally knocking the fan off of the workbench and I didn't notice the crack then.
Anyway, I proceeded to remove the 40 amp fuse that drove the fan motor and continue on my way. I'll go ahead and state the obvious that driving in Georgia without a/c is not for me, so after I got on the freeway for a bit, I dared to turn the a/c back on to test how much my engine driven fan could handle with the new more efficient radiator.
Needless to say, I was VERY impressed with the new radiator.
Before the radiator upgrade/cooling system flush with engine and elec fan:
Freeway temps: 218-225 degees F.
City temps: up to 228 degrees F.
A/C setting/fanspeed: recirculate/low (1 out of 4)
After the maintenance/upgrades and without the electric fan
Freeway temps: 209-216 degrees F.
City temps: up to 228 degrees F.
A/C setting/fanspeed: recirculate/medium (2 out of 4)
I think the city temps a bit skewed in favor of the "no electric fan" results as I have had very little stop and go traffic since the electric fan went out. The highway results are quite legitomate though. The A/C doesn't get quite as cold as it did before, but it's a hell of a lot better than no A/C at all.
When looking at my temps, it should be noted that Cherokee's run pretty hot as it is, and that my thermostat doesn't even open until 195 degrees F. Even in the winter I normally see between 198 and 211 (with the old stuff of course). I can definately see this as a permanent summer mod to put a switch on the fan relay activation circut for freeway usage. That would at least eliminate the 22 amp running draw of this fan when it's just trying to make the air a bit chillier (my A/C blows frigid when both fans are running). I'm going to listen for how often the compressor is coming on and see if that has changed with the lack of additional cooling.
In the meantime I'm hunting the local junkyards for a suitable replacement, otherwise the cheapest new replacement is $109. I remember wanting to get rid of the engine driven fan a while back, but I can't seem to come to grips with that yet, or at least my wallet can't.
More to come later on, I've got a long trip in the next few days. I can't wait to see what I can push my trip MPG to now with the new aeromods and more efficient cooling.