Winter Running Temp

Winter Running Temp

ThisGuyUKnow

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1986 CJ7 Laredo 4.0,Nv3550,D300 Twin Stick,AMC20 3.31, 31 BFG
Honda vtx1800c
Just out of curiosity, you guys out there with 258s where about does your temp sit during this time of year(talking to guys in areas staying below freezing)

I may be limiting myself to guys with certain setups but I have been running an electric fan for a while but I have been using a cheap parts house controller. For a while I noticed that even on long trips the temperature was only getting about 1/4 of the way up the gauge(I know its not an exact science since the cj gauge has no numbers) but during the summer with the fan working right the temp sat right in the middle.

As it would turn out the crappy controller for the fan fell apart and hasnt been operating. Which means my fan has not been kicking on while driving around... and i have made some long trips. My first thought was that the sensor or gauge was bad but I think I would know by now if the engine were overheating in the form of the engine blowing up and the coolant isnt boiling over so I think the gauge is good.

So has anyone noticed similar temperatures... I highly doubt that my cooling system is just that awesome considering the rad is original and has alot of bent up fins. I just find it weird that even with the lower temps that the ambient air is just that cold that the engine cant heat up. Cause my 360 has no problem getting hot enough for the fan to kick on and if it weren't working i am pretty sure it could overheat.

I'm not one to look a gift horse in the mouth but should I be worried? I am rewiring the fan tomorrow but it seems like its never going to kick on and to be honest I would like the engine to run a little warmer if for anything to maybe let my blower blow a tad warmer. I am thinking about putting a little something to block some of the grill off kinda like i see on some of the diesels running around here.
 
190 degrees
The running temp should be 190 degrees summer or winter. When you start up the Jeep and the engine is cold the thermostat will be closed. Coolant will circulate through the engine but not the radiator. When the engine warms up to 190 degrees the thermostat will open sending coolant through the radiator. Of course it won't take as long to warm up in the summer but the short answer is 190 degrees.
I wouldn't worry but I have a strong preference for a calibrated temperature gauge that has degrees not just H and C. You say your gauge only gets a quarter of the way up. That sounds normal. The factory "H-C" gauge has more room at the high end.

That electric fan should be using a thermostat so it won't kick in until the engine gets hot.

You say you want the engine to run a little warmer. You could get a different thermostat such as 210 degrees but I would not advise that. The factory wants that engine running at 190 degrees and the heater should work just fine.



.
 
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It's been 40° at best around here lately. I'm running a 195° thermostat. Temp gauge rises to just slightly into the green range and holds steady. I'm getting roughly 120° air out the defroster with the outside air intake open.

Seems like decent efficiency for both the radiator and climate control systems :)
 
Do you know what temp. thermostat is in it now?
It might be stuck open and not letting the engine warm up all the way.
 
factory is 195 i'm running a 180 tstat right now still haven't changed it from summer. yeah i know you shouldn't have to change em out but i like it to run a little cooler in the summer, seems to run a little better to me. oh and i agree with olddog on this one to, does your heater get warm or stay cool/cold.
 
I stand corrected

I run this controller
Flex-a-lite 31165 - Flex-a-lite Variable Speed Controllers - Overview - SummitRacing.com
I have a 91 cherokee t-stat and a google search found mixed results of 160 deg and 190 deg. I called oreillys and they list it as 190 but I think its opening up at lower temp that would make sense. The sensor is a fin probe and should be set out the box to kick on at 190. since it is not kicking on i am assuming that the coolant is not warming up to 190 deg as normally i find these to be fairly reliable. I do know the t-stat is opening up as the rad is getting hot to the touch... it wouldn't do that if the t-stat were not opening up to let fluid in.
 
Wait a second
There are 2 thermostats and I want to make sure none of us get confused.
There is the OEM coolant thermostat for the radiator. This comes on all engines. It controls when the coolant starts to flow into the radiator. THIS is the thermostat that I was talking about being 190 degrees and was later corrected as being 195 degrees.
Now the electric fan has it's own thermostat. This fan thermostat controls when the fan should be running. It is okay for this to be at a higher temp.
First the engine reaches 190 degrees and coolant starts to flow into the radiator. At first the radiator is cold and now gets the hot water from the engine. There is another thermostat to turn on the fan when the radiator gets hot.
These 2 thermostats work together to keep the engine coolant at about 195 degrees. The electric fan may not come on very often in the winter because you don't need much air flow to keep things cool if the air is freezing.


You originally said your OEM temp gauge only goes 1/4 of the way up when you drive your jeep. That may be normal.
A better temp gauge will show us an actual temperature.
If your engine is running too cool then you may have a bad OEM Coolant thermostat (not the one for the fan). If this thermostat is stuck open then your engine may never get up to temp.
 
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Wait a second
There are 2 thermostats and I want to make sure none of us get confused.
There is the OEM coolant thermostat for the radiator. This comes on all engines. It controls when the coolant starts to flow into the radiator. THIS is the thermostat that I was talking about being 190 degrees and was later corrected as being 195 degrees.
Now the electric fan has it's own thermostat. This fan thermostat controls when the fan should be running. It is okay for this to be at a higher temp.
First the engine reaches 190 degrees and coolant starts to flow into the radiator. At first the radiator is cold and now gets the hot water from the engine. There is another thermostat to turn on the fan when the radiator gets hot.
These 2 thermostats work together to keep the engine coolant at about 195 degrees. The electric fan may not come on very often in the winter because you don't need much air flow to keep things cool if the air is freezing.


You originally said your OEM temp gauge only goes 1/4 of the way up when you drive your jeep. That may be normal.
A better temp gauge will show us an actual temperature.
If your engine is running too cool then you may have a bad OEM Coolant thermostat (not the one for the fan). If this thermostat is stuck open then your engine may never get up to temp.

I have been following along dave... I want my engine to run at 190=195 deg. What I am saying is its not getting there. I may drop into the mechanic and see if he has an infrared thermometer to confirm. My major consider is I have computerized fuel injection and the computer will mix the fuel differently depending on engine temp. My concern is that if the fan which is set to come on at 60% power at 190-195 is never kicking on at all which makes me think that I am not reaching the correct operating temperature. Since i have a 4.0 head I installed a partshouse stock t-stat fo a 91-95 cherokee. I am thinking that I ended up with a 160 deg t-stat instead of a 190 as i see there are some online listed for that temp. so the coolant is flowing into the rad at 160 deg combined with the freezing air may explain why I am not reaching operating temps. obviously I need to turn the fan's t-stat to kick on higher than 195.

I drove the jeep all the way to galesburg (40 miles) and back the other week with the cooling fan completely removed and never even got past the 1/4 of the way. something is working too good...
 
If your coolant is never getting up to 195 degrees then the problem is the thermostat for the coolant. Get a 195 degree thermostat.
Do not use a infrared thermometer to check your temp. Many engine parts get to be much hotter than 195. some are much cooler. We are worried about the temp of the coolant. The best way to read that is with the in-dash gauge (although you already know what I think of the OEM H-C gauge)
I say replace the coolant thermostat first. They only cost a couple of dollars.

the problem is not the thermostat for the fan. That shouldn't even come into the picture until the coolant circulates through the radiator. That is were the OEM thermostat comes in.
 
If your coolant is never getting up to 195 degrees then the problem is the thermostat for the coolant. Get a 195 degree thermostat.
Do not use a infrared thermometer to check your temp. Many engine parts get to be much hotter than 195. some are much cooler. We are worried about the temp of the coolant. The best way to read that is with the in-dash gauge (although you already know what I think of the OEM H-C gauge)
I say replace the coolant thermostat first. They only cost a couple of dollars.

the problem is not the thermostat for the fan. That shouldn't even come into the picture until the coolant circulates through the radiator. That is were the OEM thermostat comes in.

Thats what I am saying the coolant is circulating through the rad so i only mention the fan tstat because i Know it is set properly so if its not kicking on it means the coolant isnt getting to 195.. Anyway I agree with you on a new tsat for the coolant. I just wanted to see if this is normal and looks like its not.
 
I am thinking that I ended up with a 160 deg t-stat instead of a 190
I would start by replacing that thermostat with a 195 degree thermostat.
 
It started getting hot enough to kick on the fan at idle today. On the HWY even with a peice of cardboard cover part of the rad it drops way down. I dont know why its heating up at idle now all i did was actually wire up the fan. Before the fan was there but wasnt wired and it would idle and never heat up.... I hate jeeps sometimes. sometimes things do or dont do stuff for no explainable reason.
 

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