Hi guys, i was just wondering if i could get a new setup to work like/better than the factory set up. I have a 90 Cherokee with the 4.0 and i am converting to the open cooling system. I am doing this because i am tired of the pressure bottle cap failing for anyone wanting to get into the open vs closed debate. The new csf radiator doesn't have the spot for the temp sensor on it, so i was thinking about getting the 92+ thermostat housing and putting this sensor in it http://www.jegs.com/i/Be+Cool+Radiat...75099/10002/-1 and extending the factory wires up to the sensor. i wanted this sensor because of the 210 on 190 off, those are great presets in my mind. I would probably just get the whole system http://www.jegs.com/i/Be+Cool+Radiators/134/75098/10002/-1
but i would rather just buy the sensor and make the computer do the job over spending the $100 for the whole kit.
If anyone has done something different and had it work, besides a manual switch, i know i will forget to turn it on, please let me know.
Thank you for your time!
Steve

 

Sounds good. The factory one comes on at 208* IIRC.

You do know about the Napa 703-1396 coolant bottle cap that fixes the issue on the closed system, right?

 

Where 'bouts is the OE temp sender located in the OE "closed system" rad?

 

Driver's side bottom of radiator tank. Near where the trans cooler lines go in.

 

Its not just the cap that upsets me, its having to burp the system and never knowing that you got all the air out that is upsetting too. I am just over that whole system lol. hoses going all over the place...... It worked great for the first couple years of the jeeps life, but i just dont want to deal with it anymore. it could be lazyness a bit too im not going to rule that out, but the last time the system let me down we were about 20 miles from civilization, it was a long walk thats for sure. i thought i had an extra cap with us, but it was nowhere to be found.

 

you can see the wires coming out of the sensor on the radiator. on the lower driver side

 

I understand. I was posting that more for others' benefit in case they never heard of it.

 

I would be cautious about that aftermarket sensor (and relocation) correctly signaling the ECU/efan. Sense the OE factory rad sensor is located at the coolest/coldest part of the cooling system, it may signal the ECU/efan much differently than a aftermarket sensor relocated to the hottest part of the cooling system (t-stat cover). Sounds like a great idea but I would feel more comfortable with some way to verify coolant temps (efan operation) other than the factory dash gauge just to be safe.

Like crusier said, try a good bottle cap 1st. Both our '06 Saturn VUE (3.5L V6 Honda VTEC) and '09 'yota RAV4 (3.5L V6) have closed cooling systems and they work flawless, right down to the caps on the pressurized bottles. Must be a bazillion GM p/u's out there with closed cooling systems.

I never have understood this "burping thing"......or folks saying a closed cooling system is difficult "to burp". On a closed cooling system, the moment the motor starts, coolant starts flowing to/thru the bottle. If coolant is flowing, any air in the system is flowing with the coolant and air naturally rises in a liquid. The moment both coolant and air reach the bottle, on a "closed system", air is separated from the coolant in the bottle (unless one lets the bottle get dry). This separation of air from the circulating coolant allows only coolant and no air to return to the cooling system, no? With a open cooling system, the only way air escapes is when the pressure rating of the rad cap is reached. U gotta have a good cap with either system and open or closed systems makes no difference regarding cooling performance.

 

You can lengthen the factory temp plug and use the newer chrysler factory sensor. The 92 and up sensor kicks on a little earlier than the Renix one due to computer and resistor stuff. I have heard the 91 radiator still has the sensor in the radiator(same one as Renix).

 

Out of curiousity, what does the Renix book say "fan on" temp is?

 

I will agree with you on the burping, i always thought i had all the air out nice and easy, but you see some stories on here that have always made me wonder if i had all the air out or not.
I also want an open cooling system because i like to be able to open a cap and see there is coolant in there. I know it sounds stupid, and even to me it sounds dumb as a stand alone argument, but it just feels weird to not have that option.

 

i was under the impression that the later year sensor was not an on off switch like the renix ones are. that it used a different calculation or something to switch on.
My new radiator is a csf 3 row and there is no spot for the sensor. I was just hoping to sort this all out before i put it in so i know my fan will work.

 

i have no idea, mine wasnt working so i had it wired up to where the ac would kick the fan on, but i could unplug the compressor so it wouldnt work the engine but the fan would stay on.

 

I think if i would have learned about this before the last stranding that i would have been game, but after that hike, i was ready to just blow the whole jeep up haha. the radiator got ordered the next day and now im just waiting for some hoses to come in before putting it in. was trying to find a way to get the fan wired up to work automatically from people with more experience than i. I have found people saying use a corvette switch, but i have also found people saying that switch doesnt work. I do owe you and a couple others on here a big thank you too btw. I have been lurking here a long time, but never posted because of that handy search feature i have found my same questions asked over and over again, so i just use that info instead of reasking again lol.

 

I think 208*.