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what temp does your electric fan come on

ehall

ehall

NAXJA Member
NAXJA Member
Location
Southern Maryland
My fan didn't seem to be working, but yesterday while idling in traffic the engine temp crept up to approx 230 and I heard the electric fan start running. I may have "fixed" it while swapping relays and whatnot or something.

Anyways, the FSM says it's supposed to come on at 190. I'm wondering what is the normal temp for most 4.0 HO engines.
 
Is a manual switch is simple as adding a relay and wiring power to the fan?
I don't think my E fan comes on at all in my 89
 
Hallo Jeeper. The best solution imo is to have a relay on the hot wire of the fan.
for the fanconnector.( for replacement) A jumpwire from the battery with a 20 amp fuse to the relay pin 30 and a connection from pin 87 to the hot fanwire (green).
A bridge from 30 to 85. From pin 86 to a switch in the cabin.
The big advantage is that there is no high current into the cabin and the switch will not heated. And you have to look only for a ground in the cabin.
p.s. this has been stolen from magimerlin. sorry:spin1:
 
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ehall said:
My fan didn't seem to be working, but yesterday while idling in traffic the engine temp crept up to approx 230 and I heard the electric fan start running. I may have "fixed" it while swapping relays and whatnot or something.

Anyways, the FSM says it's supposed to come on at 190. I'm wondering what is the normal temp for most 4.0 HO engines.
Click to expand...

Mine comes on between 220 and 230. thats according to my gauge, which is probably not that accurate.
 
Comes on at 220 (too late IMO, I don't like it to get that hot!) and goes off at 190. For the guys that don't know if theirs is working, flip on the defroster, and it should start the E fan. If not, it's DOA. If you want to manually start the E fan without wiring a switch, you can use the defroster method, but if it is a bad overheating issue, this is of no use. The best thing to do is find out why it is getting to 220, and fix that problem. If it's not overheating, and you just want the fan to come on sooner than 220 (like me) get an aftermarket adjustable thermostat, and rewire the E fan to the adjustable thermostat. Not a big deal. The new thermostat also saves you from having to manually turn the fan on when using air or defrost, because you can just jump it right into the existing wires without disconnecting anything.
 
There are instructions someplace in here on how to wire a resister into the existing fan harness that will automatically turn the fan on at a lower temp.
 
Ray H said:
There are instructions someplace in here on how to wire a resister into the existing fan harness that will automatically turn the fan on at a lower temp.
Click to expand...
Been looking for that write up... Anyone know where to find it?

Also, sorry for a dumb question, but what is the diff between a GDI and a CSF rad? Is that just the brand? I saw this proliance readyrad (link below) 3 row for cheap, and when researching that brand radiator, some sources said the readyrad is a GDI unit.... ??? confused.

http://store.summitracing.com/partdetail.asp?autofilter=1&part=PLI-432268&N=700+4294925005+4294908280+4294908279+4294924500+115&autoview=sku

EDIT... sorry for the OT rad question, I have like three cooling threads open at once. LOL
 
Found it.
Here ya go.
http://www.angelfire.com/my/fan/CTS.html

Oh, and GDI and CSF are radiator manufacturers. Ive got one of each (GDI in my XJ and CSF in my wifes TJ) and they seem to be of good and equal quality.
 
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ehanvey said:
My Electric fan works great, comes on about 210 and goes off at 190. Only problem, it makes a loud rumbling noise when it is on. Loose? Bad bearing? How difficult to fix?
Click to expand...

sounds like bearings... easy upgrade...

http://www.jegs.com/i/JEGS/555/52105/10002/-1

555-52105.gif
 
I swear my fan never comes on when the temp goes up. My temp will sometimes go barely above 210 and no eFan. The fan works, when I turn the AC on the fan cycles on/off.

I still need to just do the hardwired switch into it.
 
I have a ?: When does the fan kick on w/ the 4Kohm resistor? Right now I have the CoolantTS disco'd so the fan stays on all the time(97 ecu won't engage a/c&aux). I used a scan gauge and the ecu thinks it's -40* when disco'd. Now I thought that the ecu uses a richer fuel map when it is colder than, say 160*(definitely don't use a 160* t-stat). So if your 4Kohm resistor is tricking the ecu to think it's 190* out instead 220*, what happens when it's 190* out and the ecu thinks it's 160*?
edit: I just read Dino's writeup: The 4K tricks the ecu by 10-15 degrees--210on/185off instead of 220on/200off--to turn on/off the e-fan, but somehow tricks the rich warm-up loop by 30*(135* instead of 165*). I happen to have a 180* t-stat, so I might give it a shot.
 
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