factory cooling

[pauldo39]

Yardape, where does your temp needle point when your temp is around 220? I know this sounds repetitive but the reason I'm asking is that I don't have a more scientific way of measuring what temp the coolant is at at any given point in time other than the gauge itself. I've heard so many different temps at which the aux fan is supposed to kick on and take control (anywhere from 210 to 230 or so, can't be both!) but I think i'm gonna go with eagle on that one, at 217. But if that's true, and the temp gauge is setup the way I think it is, then my fan isn't kicking on until about 223 or 224, which to me is pushing it. Or, as I've heard, the gauges can get notoriously inaccurate especially when they get older, so mine may be reading hotter than what it really is. I'd like to know where you draw the line on your gauge and if you think I may just have a problem with my gauge, thanks.

 

[pauldo39]

thanks for the tip, krakhedd, I just found out my neighbor has a belt tension gauge and I have all the necessary sockets so I think I'm gonna go ahead and do it myself. Is 160 lbs a good number to shoot for?

 

[pauldo39]

I got my belt adjusted, and all seems to be well.

 

[viperbaron]

I put a 160 deg thermostat in my '98 with the 4.0L. It still inches up to the 210 mark. It just takes a bit longer to get there.
Now, here in Colorado, this summer has been a bit hot, but on the cooler days (below80), it may not hit 210 deg.

 

[pauldo39]

With a 160 tstat, does your jeep smell like its running rich even after driving for awhile? One thing I noticed about my jeep was that it would smell like it was running rich even after trips of 60 miles or more, especially when the temp gauge was around probably 180-190 or so. When traffic would slow and the temp would rise up to 210 or higher, and when I'd arrive at my destination with the temp at 210 or so, the smell would be gone. I first thought maybe my O2 sensor was failing, but the smell went away when the vehicle was really warm. Now I'm starting to wonder if the lower than OEM tstat is causing the vehicle to run rich. Are you having the same issue, and does your jeep still exceed 210 when idling for long periods on hot days, even with the 160?

 

[viperbaron]

No smell. I've read articles where the discussions were about an intentional design factor was to have the 4.0L engine run hot to facilitate fuel economy. I haven't noticed any adverse effect, smell or fuel economy...power nothing.
The 160 thermostat has been a good thing so far.
Yes, it still inches up to the 210 deg mark on hot days and ideling. Someday going to put a dual elect fan and remove the factory clutch fan.
BUT! It never gets past 215 on even the hotest days with the A/C on.
I love this little Jeep!

 

[partsbill]

I have a 94 XJ with a 4.0 and I am just wondering how the temperature actually is supposed to behave when idling in hot weather. I have replaced the thermostat with a 180, chemically flushed the radiator twice (in good shape I think because highway driving the jeep runs around 190 to 200 no matter what), have a relatively new water pump, and just yesterday replaced the fan clutch. It seems as if the system is in good shape for its age, yet as it sits idling the temp will raise to about 220 or so then the electric fan comes on and slowly lowers the temp. Am I making a bigger deal out of this than it really is? I would like to know if they are actually designed to run hot like this. Thank you for any input.

I read all the replies and thought I would add mine as well. Went the whole route a year ago. New tstat, no tstat, waterpump, fan clutch; w and w/o the slot cut, first one then another factory radiator(I work at a Jeep dealer) and then finally went off the deep end. I bought a plain jane $165 "3"core radiator. WOW!!!! What a difference 1 extra row makes. Just last week here in North Carolina, ambient temps @97 at lunch, heat index@112, right at my nap time after lunch. Had the jeep running with max ac on at idle, gage stayed pegged at @205-210 for 40 minutes in the sun with NO forward movement. Told a mechanic who has had problems similar to yours with his Jeep and didn't believe a 3-core would make that much difference, borrowed my jeep for the afternoon and let in idle with the air on for 3 separate time periods and his high tech??? mechanic tools could only muster a whopping 211 degrees. Get a 3-core radiator and forget the hassle you once had and move on to something fun.

Bill

 

[pauldo39]

That's interesting that your exhaust doesn't smell rich... maybe my o2 sensor is what's acting up, i don't know. Anyway, my mileage is still in the 20's on the highway so I'm not complaining; do you switch out the 160 in the winter for heat purposes? Partsbill, I've definitely thought about going your route in the past, as SO many people seem to have xj cooling problems... working at a jeep dealer I'm sure you've seen your fair share of cooling issues. It still continues to bewilder me though that some people say how they've replaced the radiator with a 3 row, put in a hi-perf w/p, changed hoses, put in a lower * tstat, bigger fans, etc... and still have issues. But you can't argue with the logic that a bigger radiator has to work better!! 165, you really can't go wrong. Is that using a standard 195 tstat?

 

[pauldo39]

Has anyone here ever wired their aux fan to a manual switch inside the vehicle and would recommend doing so? (possible quick fix before I get the money and time to get a 3 row)

 

[NotMatt]

I have my aux fan wired to a switch and I find that it doesn't make much difference if I turn it on or leave it off, since the fan will come on eventually if things get too hot. Only time I use it now is when I'm offroad and moving slowly... seems to help keep the temp at or below 210 if I just turn it on before I start out for the day and keep it running the whole time I've got the motor running (need to wire it to ignition instead of constant though as it gets annoying flipping it on and off all the time when I stop).

Basically, it can't hurt... but it's not an appropriate fix for an inadequate cooling system.

 

[partsbill]

Has anyone here ever wired their aux fan to a manual switch inside the vehicle and would recommend doing so? (possible quick fix before I get the money and time to get a 3 row)

There's not a quick and painless fix for the problem, but an adequate one. The radiator is the only way to go. I haven't done it lately but when I was having my problems with it, I searched this forum forum for cooling issues and over 90% were solved by the 3-core radiator. I must have spent over $300 and countless hours installing and worrying about it before I got it fixed.

 

[krakhedd]

With a 160 tstat, does your jeep smell like its running rich even after driving for awhile? One thing I noticed about my jeep was that it would smell like it was running rich even after trips of 60 miles or more, especially when the temp gauge was around probably 180-190 or so. When traffic would slow and the temp would rise up to 210 or higher, and when I'd arrive at my destination with the temp at 210 or so, the smell would be gone. I first thought maybe my O2 sensor was failing, but the smell went away when the vehicle was really warm. Now I'm starting to wonder if the lower than OEM tstat is causing the vehicle to run rich. Are you having the same issue, and does your jeep still exceed 210 when idling for long periods on hot days, even with the 160?

Refer to my post earlier in this thread.....160 would be more dramatic than 180....

 

[pauldo39]

Krakhedd what you said earlier really makes sense... basically the factory cooling system is designed to keep the temp at a certain point, engine will run richer until it warms up? I just thought it was interesting that viperbaron had a 160 and it was working fine for him. I guess I'm really just avoiding the inevitable with the radiator. Any metal 3 row is probably sufficient from what I read in these forums, correct?

 

[partsbill]

Krakhedd what you said earlier really makes sense... basically the factory cooling system is designed to keep the temp at a certain point, engine will run richer until it warms up? I just thought it was interesting that viperbaron had a 160 and it was working fine for him. I guess I'm really just avoiding the inevitable with the radiator. Any metal 3 row is probably sufficient from what I read in these forums, correct?

I think mine was from 1800radiators.com

 

[krakhedd]

Do a little searching. I don't remember the name of the thread, but there was something going around not too long ago (or maybe I found it via search myself) about the issue. It basically said to stay clear of GDI; there was some company based in CO that this dude hand-makes them, and they only cost I think around $160 DELIVERED! 3-row, I think copper construction. I think the thread said brass was best, but most expensive - copper and aluminum are both good, there was some argument I think against alum, but I don't remember what it was.

You'll know you've found the correct thread if you find this company I'm talking about. They had something posted on their website about the Christian life and message and whatnot. I actually had called the guy, and he seemed pretty cool.

160* is overkill. I had one, and all it meant was my coolant system ran ALL THE TIME. Also, I didn't get nearly enough heat in the winter. 180 is a good number though. Earlier in this thread, somebody said the reason for a tstat is to keep the engine warm, because it runs better. I forget the logic behind it, but he's correct, to a point. Your engine will run better with a 180*, but will circulate coolant more, so it's a bit of a tradeoff. I will use a 180* in every XJ I may ever own.

 

[viperbaron]

160* is overkill. I had one, and all it meant was my coolant system ran ALL THE TIME.

Krak did not state anything to support his assessment of overkill for a 160 deg thermostat. Obviously, it was not overkill as it is working fine.
Engine coolant "runs" all the time anyway. It is constantly circulating through the engine block and when the thermostat opens up, it will also circulate through the radiator. Which brings me to say; "So what if it runs all the time?"
Shade tree mechanics. I hear echoes of a quote from the Forrest Gump movie...

 

[langer1]

GDI's are hand made also, IN MEXICO

 

[pauldo39]

I think aluminum radiators just break the bank because they're more expensive, is this correct? I have yet to run into the thread where they recommended against GDI, but I just checked out modine's website and it appears they are building aftermarket radiators with the name proliance now? I'll have to start looking for that thread you were talking about krakhedd and make a decision on brand or supplier to go with.

 

[Atl XJ]

GDI's are hand made also, IN MEXICO

I actually hear they are made in China these days and the older better quality ones were made in Mexico.

Btw, after reading through this post there is a lot of praise for three row radiators. A three row does not cool any better than a good quality two row like Modine. You are actually worse off having one in the long run since the smaller coolant passages like to clog.

 

[XJXJ]

The MAIN thing is to get the cooling under control. Thermostats, open/closed conversions and all of that are bandaids. If your fans/belts are good and you don't have a cracked head or leaking gasket, then the only thing that will regulate engine temperature is a new "clean" radiator.

2 rows, 3 rows, it's all open for debate but the bottom line is you are gambling every minute you operate with a lacking radiator and the longer you delay the more likely you may face potential engine damage. I recently had a friend ask me about oil for his new Ford pickup. I laughed and said that is not nearly as important to longevity as the cooling system and NEVER allowing that engine to get into overheat state. Once that happens, things will never be quite the same. If something springs a leak and it get's hot, shutdown and deal with-it, either roadside repair or tow. Of course, most folks prefer to learn these lessons the hard way...

I am very happy with a $150 CSF rad. It's a little thicker so qualify your motor mounts or else you may get a surprise from the fan clutch. But in SW desert heat, the e-fan handles things perfectly and there's never any extreme engine temps no matter how long I idle w/AC in +100F temps.

Modine looks like a great rad but I can only attest to the CSF going on two years and I'm very happy with that so far. And yes, leave the 195 thermostat in.