Hi temp under hood. Not on guage.

[Guest]

Well, took the jeep to get something welded. Notice when I got there the grill was HOT! Temp guage was about 180-185*. Nothing boiling over. No sounds. Came home and noticed the head lights were fogged! Again, temp guage in Jeep was fine. About 180-185*. No loss of coolant. No sound from radiator. Grill was HOT though. I removed the radiator cap as soon as I parked it and did a temp check of the coolant with my digital read out. It showed 184* I fired up the jeep and I could see the coolant flowing for a second. When temp dropped, the coolant stopped flowing. So, the t-stat is opening.

Is it possible the fan is really pulling the heat from the radiator keeping it cool thus keeping my temps cool but the heat is staying in the engine under the hood? If so, maybe some louvers are in order?

[JJsKJ]

sounds like your cooling system is working well. normal for stuff to get hot and since your not boiling over, etc. why bother spending money on louvers? talked to a guy yesterday that had louvers punched in his TJ hood and he said it caused the hot air to flow out and into his interior air intake in middle of the cowl area causing interior temps to rise. not sure if that is truly how it would happen but that is what he told me.

[Guest]

Oh wow. I think I am going to sit on it. Summer heat will be gone in a few weeks anyway. The temps are cooler than ever on the guage. Very happy with my set-up.

As for the fog in the new headlights, I might just try to seal those with some silicone.

[JJsKJ]

Oh wow. I think I am going to sit on it. Summer heat will be gone in a few weeks anyway. The temps are cooler than ever on the guage. Very happy with my set-up.

As for the fog in the new headlights, I might just try to seal those with some silicone.

Hope you are right....looking forward to cooler temps and some desert wheeling.

[Guest]

It usually starts cooling down in September.

[Guest]

Well, some of you know I am a little anal about things until they are fixed right (Thanks dad!).

I drained the coolant as I thought the mixture maybe wasn't a 50-50. More like a 85-15 (more water). So, I did a 50-50 with Peak and replaced the Prestone. Not sure what made the difference. But, took it for a drive just now (30min) and came back and the grill and hood was a lot cooler!

The Peak seems a little darker in color (in the bottle) than the Prestone (was brighter in color) did. Not sure why. But, it runs better.

UPDATE:
Here is the difference. PROPYLENE glycol based antifreeze (Prestone) and ETHYLENE glycol based antifreeze (PEAK). Prestone is green and Peak is amber.

[Mitch]

Ron,

As mentioned before, I added 4 8X8 hood louvers and it made ZERO difference in the temp gauge or unger the hood running temp. It seems to cool off a little bit sooner but nothing noticeable when running. Also putting on Tube Fenders with open sides also made ZERO difference when the engine is running.

Mitch

[Guest]

After changing the coolant seem to have fixed the under the hood temps. Weird, guage is great. Still at 177-185* range depending on what I am doing. Just under the hood felt hot. It was better after fluid change. I think it had to do with the fluid mix.

[peteyg]

You know that running the 4.0 at 185 is too cold, right? The engine is DESIGNED to run at 210, and the emissions equipment will not work right at lower temps. There's a chance that your computer will stick in open-loop, and you'll probably fail smog.

[Guest]

You know that running the 4.0 at 185 is too cold, right? The engine is DESIGNED to run at 210, and the emissions equipment will not work right at lower temps. There's a chance that your computer will stick in open-loop, and you'll probably fail smog.

Respectfully disagree. I was told a OBD1 computer is concidered warm after 177* (closed loop) Although, most online say 140-160* depending on your sensors. That's why some say the 160* stat is a gamble if it is closed loop while the 180* stat is a safe bet.

I have ran a 180* stat in my cars/trucks/suv since late 90's I think. When I moved to the high desert. Never had an issue with smog.

Again, this is only my personal experience. Not theory.

[Guest]

Found this.
http://temp.corvetteforum.net/c4/vader86/160.html
There are those on the forum who will tell you that the engine will run in open loop all the time with a 160....these people do not understand the criteria for closed loop operation, and just need to STFU. There are several conditions for Closed Loop operation, mainly that the ECM's timers have gone off (The cold one is 300 seconds), coolant reaches set temp (about 140F), and the O2 reaches ~600F (350C). By the time your oil temperature reaches 160, and those timers have gone off, you will be in closed loop, in nearly all cases. You can actually see it go into closed loop if you watch both your "Instant MPG" and coolant gauge. Watch what happens (at the same rpm/throttle) when it crosses 140F.

[peteyg]

you're right on the obdI...sorry, I thought you had a TJ. OBDII TJ's do require 195+ for closed loop.

Just a note: Quoting off a corvette forum is apples to oranges. Two entirely different engine management systems. If you're going to quote, make sure it's related to the engine system you're talking about.

[Guest]

you're right on the obdI...sorry, I thought you had a TJ. OBDII TJ's do require 195+ for closed loop.

Just a note: Quoting off a corvette forum is apples to oranges. Two entirely different engine management systems. If you're going to quote, make sure it's related to the engine system you're talking about.

Fair enough. It was more of a generic way of saying the not all cars need to be 195* without digging for a 4.0 Jeep motor

It's funny. True story. I have had a suburban, Nissan p/u, and a Jeep grand. All three had bad cats. So bad, when they cut it off, the crap went all over the floor. Like brick dust and junk. In all three cases, I had smogged them the SAME DAY and all passed smog! Only reason why I went to the muffler shop is because they were low in power. Smog shop said to have a muffler place look at them. I have no google links to explain this. Sorry

[2blk2drs]

I drained the coolant as I thought the mixture maybe wasn't a 50-50. More like a 85-15 (more water). So, I did a 50-50 with Peak and replaced the Prestone. Not sure what made the difference. But, took it for a drive just now (30min) and came back and the grill and hood was a lot cooler!

Hmm this doesnt seem to fit with how what i have seen, more water usually makes it run cooler, with less resistsance to freezing.

UPDATE:
Here is the difference. PROPYLENE glycol based antifreeze (Prestone) and ETHYLENE glycol based antifreeze (PEAK). Prestone is [COLOR="Lime"]green[/COLOR] and Peak is [COLOR="Orange"]amber[/COLOR].

Soo the Peak looks like pee after you drink a Rockstar, or the morning after a long night drinking?
Man, i gotta start bottling this stuff!
:beer:

[CaptainSavi]

I might have missed it, but what should the temp by on a 2006 Wrangler X 4 cylinder?

I also found no change in engine temp after the louvers I installed.