Overheating is not solved

[robs]

Yes, I have searched... many, many times..

Here's where I'm at... 95XJ, AW4, 160k on the clock, well maintained it's whole life... (know original owner).

Anytime outside temp over 80°F... one good uphill blast in the woods and it's at 230°F... if I don't let it cool down, each additional blast will keep adding 5°F to it.

On the interstate, once the converter unlocks you can see the gage start to rise.

Have verified outlet temp with temp gun.

List of what's been done.

-GDI radiator
-Now a CSF radiator
-Plate and coil tranny cooler
-Robert Shaw high flow t-stat
-New fan clutch
-Flowkooler high volume pump
-Water wetter
-Forced cooled hood vents

Probably some other stuff that I've forgotten about...

I want to do Moab next year, but I've gotta get this solved first.

Toying with the idea of adding an additional heater core under the hood with a fan to add cooling capacity. Not sure how that would help.

I've read about the Modines, but I've already dumped 2 radiators in this thing after everyone said "yeah, worked for me" and the results just remained the same...

[logdog]

First thing I would do is lose the t-stat and get one from the dealership. Next get a Modine radiator. Its only a two row but the cells are much bigger, and holds more fluid.

You may consider a tranny cooler, and or an oil cooler.

[czidesigns]

I have an 89 that has had the cooling demons for quite a while now. With the differences in cooling systems it really seems that these problems should not cross over from one system to the other (open or closed). I think from my experiences that the blocks might actually decompose over time and produce sedement that flows through the cooling system clogging up passages, the smaller they are the easier they clog. The stock radiators and many aftermarket radiators have very small passages, adding more rows actually means smaller passages, not larger. I haven't really found a solution but have kept my demons at bay by doing a open system conversion and routine system backflushing.

[Harvo]

A buddy of mine had similar issues with his. He tried about everythingyou did and eventually ended up cutting a hole in the hood and putting an electric pull fan there. His conclusion was that his york compressor and conical K&N filled in the last little bit of space under the hood. He figured there was nowhere for the heat to escape, keeping the engine too hot, and keeping an already overtaxed system from being able to cool it.

Harve Out.

[old_man]

You mentioned something that might be related. You said when the torque converter unlocks. It is possible that the tranny oil cooler is dumping way too much heat into the radiator because of a faulty tranny. Try taking the tranny cooler in the radiator out of the loop and see what happens with the engine.

[Goatman]

Yes, I have searched... many, many times..

Here's where I'm at... 95XJ, AW4, 160k on the clock, well maintained it's whole life... (know original owner).

Anytime outside temp over 80°F... one good uphill blast in the woods and it's at 230°F... if I don't let it cool down, each additional blast will keep adding 5°F to it.

On the interstate, once the converter unlocks you can see the gage start to rise.

Have verified outlet temp with temp gun.

List of what's been done.

-GDI radiator
-Now a CSF radiator
-Plate and coil tranny cooler
-Robert Shaw high flow t-stat
-New fan clutch
-Flowkooler high volume pump
-Water wetter
-Forced cooled hood vents

Probably some other stuff that I've forgotten about...

I want to do Moab next year, but I've gotta get this solved first.

Toying with the idea of adding an additional heater core under the hood with a fan to add cooling capacity. Not sure how that would help.

I've read about the Modines, but I've already dumped 2 radiators in this thing after everyone said "yeah, worked for me" and the results just remained the same...

How long has it been doing this? What was the symptom that caused you to do the other mods? What did it do, and what was the last mod that you made?

Have you had the radiator sniffed for hydrocarbons?

[BillR]

Have you had the radiator sniffed for hydrocarbons?
Good thought...possible head gasket or cracked head.
The other thing I thought of was some blocked water passages in the block. Have you done a flush that includes the engine?

[robs]

Good thoughts...

It started right after I started wheeling it a couple years ago... in the woods... good uphill blast and it hits 230°F...

Did the GDI... no help... then started do the other mods one at a time... None of them have made any difference...

The tranny oil cooler was also added by it's lonesome without help...

Hood vents, (powered) don't do crap...

http://members.intertek.net/~simons5/xj/vent6.jpg

No snifs for hydrocarbons in the system.... the plugs look great, the oil looks great (no foaming), and there's no oil in the radiator or loss of antifreeze... Don't mean it's not a problem...

The original owner had flushed it routinely... the inside of the block looks great.. When I had the waterpump out, I did feel around, and there was no debris in that area and I ran a magnet down around the bottom of the cylinder... nothing... there's no debris behind the t-stat housing in the head...

I do think it's related to the tranny... it's creating heat that's overcoming my system's capacity... On the interstate, I've played games of unlocking the converter (turning on the brake lights unlocks it) and the temp starts climbing on uphill runs under power... but dropping into third and letting it lock, you can still apply lots of power without the temp starting to rise...

The tranny operates beautifully... the fluid is red and smells fine...

I was suprised the plate and coil cooler didn't help...

[Goatman]

I'm wondering if you really have a problem. Does it get into the red if you continue to push it, or just get up to around 230*?

Have you tried a mechanical guage to check the accuracy or your guage?

If you don't have a problem under normal driving conditions, but the temp goes up under certain high load conditions....it could be perfectly normal as long as it doesn't go into the red, or get very close to the red.

[90KrawlerXJ]

My only question is: Do you have a separate trans cooler? If not you absolutely need to add one. Autos(especially the weak AW4) will not survive under heavy use with the radiator cooling. Trust me I've proved it in my XJ. $3200 for a rebuilt trans.

[90KrawlerXJ]

Also the electric fan and thermostat setting for it are critical with the stock 4.0L.

[Planetcat]

Yes, I have searched... many, many times..

Anytime outside temp over 80°F... one good uphill blast in the woods and it's at 230°F... if I don't let it cool down, each additional blast will keep adding 5°F to it.

List of what's been done.

-GDI radiator
-Now a CSF radiator
-Plate and coil tranny cooler
-Robert Shaw high flow t-stat
-New fan clutch
-Flowkooler high volume pump
-Water wetter
-Forced cooled hood vents

I've read about the Modines, but I've already dumped 2 radiators in this thing after everyone said "yeah, worked for me" and the results just remained the same...

I have a '96 XJ country 4.0, AW4, etc. I replaced similar stuff that you did with the same exact things (flowkooler, robert shaw, clutch, water wetter, etc.), except put in a 3-row modine. Still boiled over, similar to how yours does (80+* outside temps, and just starts creeping up until boilover). I solved the problem when I put in a single row aluminum radiator from McCulloch Radiators http://www.alumrad.com ($150 or so). If it's like mine, you probably have the AC condender and tranny cooler up in front of the rad behind the grill. I was thinking that maybe because these things are in front of the rad, that the air is not really cool enough when it hits the 2nd and 3rd rows of the radiator. This means that you effectively have a very small tubed one row radiator. The single tube aluminum rad from McCulloch has 1-3/8" tubes. Now, I've towed my 3800 lb boat in 100* temps with it not budging over 200*. Just a theory, but my overheating problems are a thing of the past.

[Wiley Coyote]

I had similar overheat problems as you and did the same series of fixes. They all helped, but nothing really worked. The thing that finally put me in the comfort zone was spacing the back of the hood. I removed the hood from the hinges (4 bolts), added a bunch of washers and reinstalled with new, longer bolts. The rear of my hood (by the windshield) sits ½” taller than the front. The extra space allows the fan to push all of that hot air out of the engine bay and suck in new, cold air. It works awesome in traffic and when I’m doing 75 mph on the freeway my temp gauge actually drops below normal operating temperature. The mod cost me $2.98 at my local Ace Hardware and took a ½ hour to do. It’s a lot easier to get the hood spacing right if you have a buddy hold the opposite side for you.

[robs]

Yes, the electric fan is on... and there is a separate tranny cooler...

Every additional blast results in another 5°F increase... I usually back down and let it cool off (tranny in neutral, 1200 rpm idle) before it hits the red...

I have verified the temperature gauge with a IR temp gun on the Tstat housing... It was only 220°F at the time, and they were both on the money...

Planetcat, you're the first person I've heard of that had problems with the Modine.. but others people talk of are 2 row versions...

If this is truly just a capacity issue... then another radiator is in store... From what I've read, the aluminum ones have advantage simply because they can be made with wider tubes (weight issue)...

I also have a 5.0 Ford as a daily driver that had temp issues... I put a 1 row Modine in it (all they had), and it runs cool now. Planetcat has scared me on the Modine, especially given our very similar history.

[bshaw]

Something I have not seen anyone suggest yet. When you replaced your radiator did you check the back of the condensor, or do you have a/c? To make a long story short, I battled overheating problems for a month and a half during the summer. I could not figure out what the hell was going on. Replaced all kinds of shi^ and as a last resort I replaced my radiator. Well come to find out my condesor was so full of mud and other crap that is was causing my overheating problem. Month and a half of replacing parts and headaches all over a clogged condensor. After all that I disconnected my A/C and took the condensor out, and least to say I've never had a problem again with overheating. Stays at 200 and below all the time, even wheeling! Sometimes it's easy to look over the small stuff that causes big problems. Hope this might help you out!

[Planetcat]

Yes, the electric fan is on... and there is a separate tranny cooler...

Planetcat, you're the first person I've heard of that had problems with the Modine.. but others people talk of are 2 row versions...

If this is truly just a capacity issue... then another radiator is in store... From what I've read, the aluminum ones have advantage simply because they can be made with wider tubes (weight issue)...

RobS, given my theory on the overheating problem, I think the modine rad worked as designed, just didn't work in my particular application because it was a 3-row. It was brand new when I bought it and I flushed it several times thinking that maybe there was packing material in it. Flushing didn't help. I also like Wiley's idea of propping up the back of the hood to vent out the hot air, but I saw you have hood vents already, so that might only band-aid your problem. LOL.

[Dr. Dyno]

Yes, the electric fan is on... and there is a separate tranny cooler...

Every additional blast results in another 5°F increase... I usually back down and let it cool off (tranny in neutral, 1200 rpm idle) before it hits the red...

I have verified the temperature gauge with a IR temp gun on the Tstat housing... It was only 220°F at the time, and they were both on the money...

Planetcat, you're the first person I've heard of that had problems with the Modine.. but others people talk of are 2 row versions...

If this is truly just a capacity issue... then another radiator is in store... From what I've read, the aluminum ones have advantage simply because they can be made with wider tubes (weight issue)...

I still have the original 12-year-old factory 2-row radiator in my strokered Jeep and I have NO overheating issues.
Before you throw more money into another radiator, try something simple like replacing the radiator cap. If it's old, that may be the cause of your problem.
I think you should take note of what Tom said:
You mentioned something that might be related. You said when the torque converter unlocks. It is possible that the tranny oil cooler is dumping way too much heat into the radiator because of a faulty tranny. Try taking the tranny cooler in the radiator out of the loop and see what happens with the engine.
A separate external tranny cooler would allow you to divert the hot tranny fluid away from the radiator and prevent heat transfer from the tranny fluid to the coolant.

[DrMoab]

My only question is: Do you have a separate trans cooler? If not you absolutely need to add one. Autos(especially the weak AW4) will not survive under heavy use with the radiator cooling. Trust me I've proved it in my XJ. $3200 for a rebuilt trans.
I don't want to hijack this thread but why do so many think the aw4 is a weak tranny. Very very few transmissions will go 250,000-300,000 miles and give you no troubles...I see aw4s do it all the time. My dad rebuilds them for a living and he never sees them in for repairs....ever.
The biggest problem with Aw4s is the under powered cooling system. Throw a better cooler on and they will last forever.

Back on topic here...I would also say look at the a\c condenser. If it even has small rocks stuck in it from sand blowing off the highway it can dramaticly cut down on the effectivness of your cooling system.

[goodburbon]

I had similar overheating issues when I bought the jeep and for several months afterwards. I went through all of the same steps everyone else listed, My condenser was clogged, cleaned it, a rubber shroud was between the condenser and the radiator, it had collapsed and was blocking airflow, removed it. I changed the fan clutch, flushed the system a few times, added super duper coolant that lowers your cooling system temps (supposedly). changed the thermostat, and the water pump.

My problems were finally solved when I ditched the mechanical fan. I put a dual electric fan setup with a thermo switch. Never overheats now, not even in the mud revving the heck out of it and not going anywhere.

I also have a seperate tranny cooler that came with the towing package

only downside......no a/c until it warms up enough to kick on the fans or unless you are rolling. after 3-4 minutes its all grrrravy

[AJsArmor]

I think it's incredibly STUPID of all car manufacturers not to have a transmission temp gauge as standard equipment. Otherwise a lot of people, including qualified mechanics will chase what they think is a cooling problem for weeks when in fact it's the transmission that is the culprit. Install a trans temp gauge, they're cheap and worth every penny. I'd also disconnect it from the radiator, run it on it's own cooler to take the load off the radiator.

I had a similar problem with my own XJ, upgraded the radiator, opened up the passage in the t-stat housing, installed a hi-flow waterpump...still overheating issues. Replaced the headgasket and cured it. What's weird about that is I had zero symptoms of a bad head gasket, plugs were fine, coolant level stayed the same, but replacing it did the trick. Good luck!

[robs]

Replaced the headgasket and cured it. What's weird about that is I had zero symptoms of a bad head gasket, plugs were fine, coolant level stayed the same, but replacing it did the trick. Good luck!

That's the LAST THING I WANTED TO SEE... Ugh! Man... that would suck...

There's no mud in the condensor... ck'ed it... I've had the radiator out of it a few times....

[MudDawg]

I just got a very nice '91 MJ for cheap because the previous owner could not get the cooling problem resolved. He had the waterpump, t/stat, hoses replaced and a valve job done....he failed to replace the worn out rad cap..also the "professionally flushed" oem radiator was still partially plugged.

I installed a new Modine rad and new cap from NAPA..now at 75+ mph on the interstate with the a/c on...never goes above 190.

Anyways...If the hydrocarbon test is negative, the headgasket is ok. If it runs normal temps in easy everyday driving...it points to a capacity problem....Try this...run the heater at max...if it does not get hot enuff to bake a turkey, you have a fluid flow problem (assuming the engine is running hot at the time of the test)...if it is very hot, and brings the temperature down some...you have a capacity problem.

[robs]

Summer is back. So is the overheating problem.

Yes... I re-read the head gasket issue, and will do some testing...

HOWEVER.. I'm leaning more towards a capacity issue...

Apply generous throttle... the gage climbs... normal driving, it comes back down... It will do this even if I drop the tranny back into 2 or 3 gear and let it lock the converter back up...

I've got a CSF... but it might not be a normal one... the UPS guys destroyed the first two... and the third one they sent out wouldn't hook up to the tranny line (oversized 0.010")... so they might have sent me a funky one...

I'll pull it out and drive it this week... and do the heater thing (sweet my butt off)...

Everyone still pretty much happy with the Modines?

[FUNKYTEE5]

Have you tried running with the T-stat out? This should allow the coolest possible running conditions. It may raise some question/idead as to what the issue is.

FUNKYTEE5

[burntkat]

actually, believe it or not, running with the thermostat out can CAUSE overheating. Basically- the coolant doesn't stay in the radiator long enough to let go of it's heat... and just keeps getting hotter, and hotter...


very interesting thread- -I'll keep my eye on it as my Jeep tried to overheat on me today after chasing down a friend on the interstate.

[FUNKYTEE5]

That does sound feasible, but it's not usually the case when the vehicle is on the freeway with ample airflow. In every case that I've been involved with, cold running conditions and lukewarm heater output, has been because of a stuck or broken t-stat. It's not a answer, it's just another thing that you can do to gather clues as to possibly diagnosing this problem. It will change the flow characteristics through the system.

FUNKYTEE5

[JeepSpeed]

My only question is: Do you have a separate trans cooler? If not you absolutely need to add one. Autos(especially the weak AW4) will not survive under heavy use with the radiator cooling. Trust me I've proved it in my XJ. $3200 for a rebuilt trans.



Wow. You are an absolute moron.

[burntkat]

I see what you're saying, Funky. MAkes sense now you mention it that way. I thought you were suggesting it as a permanent "fix"

regarding the fellow that calls the AW4 a weak transmission. Wow. What color is the sky where you're from!!? ;)

[oardonj]

Hi my name Orlando, I have a problem and maybe you can help me. I have a code that keep on showing which is P0705 transmission range sensor circuit malfunction and also is blowing fuse 11a (20 amp) run/start/daytime light. Can you help me. I forgot I have a 1997 jeep cherokee.

Orlando

[MoabXJeeper]

I had experienced a lot of overheating probs in my '91 XJ. I took it to a radiator shop where they boiled the radiator out to clean it. That has helped a ton and when it heats up now it cools again on its own. Something to try anyway.

Von

[Roll-over]

Hi my name Orlando, I have a problem and maybe you can help me. I have a code that keep on showing which is P0705 transmission range sensor circuit malfunction and also is blowing fuse 11a (20 amp) run/start/daytime light. Can you help me. I forgot I have a 1997 jeep cherokee.

Orlando


replace the sensor. if that doesn't help then try posting your own thread.

When you're ready to do so click this: http://www.naxja.org/forum/newthread.php?do=newthread&f=43

[JeepSpeed]

regarding the fellow that calls the AW4 a weak transmission. Wow. What color is the sky where you're from!!? ;)




I think the fact that he paid $3200 to have his AW4 rebuilt is far, far more stupid.

[Fergie]

First off, no body asked what you thought, so there!

Robs- You and I must have identical XJs as we are having the EXACT same problems. Try lifting the hood in the back, and also installing a manual override for the cooling fan, then if you havent done so, remove the trans from the cooling loop completely.

Fergie

[burntkat]

well, it's good to see someone raised the mentality of the thread... ;P :laugh3:

how will installing a fan CUTOFF switch help the engine cool better?

[burntkat]

I think the fact that he paid $3200 to have his AW4 rebuilt is far, far more stupid.

I have to agree, even though nobody asked, because he coul dhave bought a BRAND NEW AW4 from Mopar for $1900. Or had his rebuilt for $1200. Or just got a low-mile unit out of a junkyard for $400 and been good to go.

[robs]

Thanks Fergie...

I talked to Bryan at http://www.alumrad.com and explained the situation... Had a very good back and forth... finally, he said... "Put in my radiator, and if it don't cure your problem, I'll buy it back"... So how can you go wrong with that????

Bryan certainly seamed to know what he was talking about for the XJ radiator issues... It shows up next Monday... I'll post what happens...

Here's his aluminum one next to a copper one... he believes the long XJ radiator results in flow problems for the smaller tubes...

http://www.alumrad.com/alucop.jpg

[burntkat]

what did it run you for that AL jobbie?

[RichP]

I notice that he seems to have eliminated the dog leg filler cap. Looking at my 98 thats gotta be a pretty good sized hole that needs to be cut in the top brace. I wonder if there are any issues clearing the hood. What are his prices like ?

[robs]

Bryan said it was a direct OEM replacement, so I'll let you know... It was a very reasonable 2 bills... shipping from AZ to IL was under $20.

[burntkat]

man- 2 bones for an all AL radiator is a STEAL!!!

[themud]

before everyone gets to excited about the alumrad being al just remember its a drop in replacement it does have plastic tanks...Im not knocking it cause I have one in my heep right now and it does get a little warm but I think its just a bad airflow design FLAW from DC..I will also be going electric once I get a/c bracket from a tj(it takes the fan clutch completely out no studs to cut)...Plus youve got to get a fan worth crap I picked up a permacool 14 fan it moves about 3000 cfm it should do the trick after I put in a good shroud..
luck
themud
ps I do agree the tranny is the problem mine does the same thing..

[robs]

Buzzzzzzzzzzzttt!!!

themud was right.

Nice radiator, but plastic ends...

Pretty tough to judge since it's only like 75F outside right now... BUT... it might be a LITTLE better, but it ain't gonna fix it...

In the driveway... zipping the engine between 2-4000 rpm with the air on high, and it stayed right at 195F...

BUT... I tied off to a tree and put in low range and just spun for a little while... NOT LONG AT ALL... jumped right up to 230F... once at 230F, it took a LONG time to come back down...

So... guess it's time to do the head gasket. :rattle: :rattle: :rattle:

[robs]

In the woods today... 96°F outside... hitting 230-240F after a few hill blasts... No real change with the Aluminum (and plastic) radiator... in fact, it heated up quicker than the CSF...

However... driving home, anytime I got over 45 mph, it ran very cool... right at 195F... the CSF never did that... Like themud is doing, it might be an airflow issue with this radiator.

[old_man]

Here are a few stupid questions I'm going to ask. I ask these because I've never seen a 4.0L overheat if it was fine mechanically.

Did you replace the radiator cap when you did the radiator? (they get old and don't hold pressure) This is a very common thing. Ideally change the cap every year or so. 16lb.

Is the lower radiator hose the type with the spring inside? (When hot and high rpms, they can collapse without the spring)

If you replaced the water pump lately, are you sure they gave you the right one. There are right and left hand rotation pumps. (They look identical on the outside, and even on the inside unless you look at the direction of the vanes)

Have you checked for hydrocarbons in the radiator? (A leaky head gasket can cause all kinds of problems in this area) This is especially important with an aluminum radiator as the hydrocarbons and byproducts will turn the coolant into an acid and eat the radiator in short order.

Have you burped the engine block to get rid of trapped air? (A trapped air bubble can cause overheating) This is done by backing out the temp sender on the back of the head.

What color is the inside of the tail pipe? (Checking for lean burn condition)

Have you pulled the spark plugs and check them for running too lean? (Running white with buildup is a symptom of running lean)

Have you checked your vacuum pressure at an idle? ( A large vacuum leak will cause the lean run scenario, most likely will have a high idle)

If you have AC, have you checked that the AC condenser isn't blocked?

Have you checked your fan clutch? (I take a piece of safety wire and wire the clutch so it can't spin and see if that fixes it.)

I've even seen engines run hot due to a plugged exhaust. Normally associated with a drop in power and sluggish accelleration.

Lean run issues can be caused by a dozen or so things. If it is a lean burn, post back and we can cover the possibilities.

This is a general list. Sorry if I asked a question that you already answered.

Lots of luck.

[robs]

Here are a few stupid questions I'm going to ask. I ask these because I've never seen a 4.0L overheat if it was fine mechanically.

Did you replace the radiator cap when you did the radiator? (they get old and don't hold pressure) This is a very common thing. Ideally change the cap every year or so. 16lb..

Great questions. THank you!

Yes. I'm on my third radiator and 5th cap.



Is the lower radiator hose the type with the spring inside? (When hot and high rpms, they can collapse without the spring)




Yes



If you replaced the water pump lately, are you sure they gave you the right one. There are right and left hand rotation pumps. (They look identical on the outside, and even on the inside unless you look at the direction of the vanes)
.

I've got a high flow waterpump now... it's vanes were the same direction as the orginal removed.



Have you checked for hydrocarbons in the radiator? (A leaky head gasket can cause all kinds of problems in this area) This is especially important with an aluminum radiator as the hydrocarbons and byproducts will turn the coolant into an acid and eat the radiator in short order.
.

This I have NOT done. I loose no coolant over a very long period of time. I've been told this is my problem. I would like to exhaust other issues before yanking off the head... :yeck:



Have you burped the engine block to get rid of trapped air? (A trapped air bubble can cause overheating) This is done by backing out the temp sender on the back of the head.
.

Couple times.



What color is the inside of the tail pipe? (Checking for lean burn condition)
.

Sooty :)


Have you pulled the spark plugs and check them for running too lean? (Running white with buildup is a symptom of running lean)
.

I've fought this for years. I've replaced plugs a few times. No real signatures of lean burn.



Have you checked your vacuum pressure at an idle? ( A large vacuum leak will cause the lean run scenario, most likely will have a high idle)

.

Not yet. Will do tonight. However, I just found a hole in the vacuum cannister, and have plugged it. It ran fine even with this system leak.




If you have AC, have you checked that the AC condenser isn't blocked?
.

Clean


Have you checked your fan clutch? (I take a piece of safety wire and wire the clutch so it can't spin and see if that fixes it.)
.

I've replaced the clutch before. I've got a flex fan to install tonight.



I've even seen engines run hot due to a plugged exhaust. Normally associated with a drop in power and sluggish accelleration.
.

Agreed. However, today, it's close to 100F outside... I flogged it on the interstate, and it never got over 210F.



Lean run issues can be caused by a dozen or so things. If it is a lean burn, post back and we can cover the possibilities.
.

Agreed.. I've changed the oxygen sensor as well..



This is a general list. Sorry if I asked a question that you already answered.

Lots of luck.

Thanks Bro! It's driving me NUTS

[Fergie]

Here is something else...

Are you going by the temp gauge you have? If so, have you checked the actual engine temp with temp gun?

Your temp gauge may be inaccurate.

I am in the same boat as you. I just switched my CSF to a Modine, removed the trans from the radaitor cooling loop, and fixed a leaky lower rad hose, along with flushing the entire system.

So, get the gauge checked, and think about installing a seperate temp gauge.

Fergie

[themud]

Here is something else...

Are you going by the temp gauge you have? If so, have you checked the actual engine temp with temp gun?

Your temp gauge may be inaccurate.

I am in the same boat as you. I just switched my CSF to a Modine, removed the trans from the radaitor cooling loop, and fixed a leaky lower rad hose, along with flushing the entire system.

So, get the gauge checked, and think about installing a seperate temp gauge.

Fergie


Yes as a matter of fact I just did that today you dont wanna know what I found just plingin that gun all over the place...The results will shock the hell out you...thermo cover 210*, exhaust 335*+, intake 300*+, sending unit for gauge 215*220*, tranny pan 150*, tranny pan near the crossover pipe 206*(OUCH), oil pan185*(all over)...I did even more things too...AND THE DAMN FAN DOES COME ON AT 218* on the dot as setup by DC...
themud


Past 210 on the guage its accutate just not linear...

[robs]

I've found the same thing with the IR gun.

My new fan clutch was a little weak, so I popped another one in last night... a much larger and stiffer one than what was on it. Don't know yet if it helped, but it definately moves more air.

[langer1]

Much the same problem here previous owned did everything to fix the problem, gave up and sold it cheap to a friend of mine. The orignal owner was a slow driver and only had the problem when pulling his boat. My buddy is a hard driver and had the over heating problem all the time.

One day the rad. just blew luckely a local radator shop is also a Jeeper and sold us the Modine radator, a three year problem was solved.
Check out Dave Rupples on the net.

[robs]

I've found the same thing with the IR gun.

My new fan clutch was a little weak, so I popped another one in last night... a much larger and stiffer one than what was on it. Don't know yet if it helped, but it definately moves more air.


New fan clutch was a little bigger too... under load, it met my new radiator... made a nice 8" diameter hole in it. :mad: :mad:

[Fergie]

Well, just drove home in +100* weather in stop and go with the AC on.

NEVER WENT ABOVE 215*!! !! !!

I installed a Modine from Napa on Sunday, and have 50/50 mix and a bottle of water wetter in it.

Also, make sure you always get a dealer fanclutch as the aftermarket ones are thicker....20/20 ehh.

Fergie

[red91]

Well, just drove home in +100* weather in stop and go with the AC on.

NEVER WENT ABOVE 215*!! !! !!

I installed a Modine from Napa on Sunday, and have 50/50 mix and a bottle of water wetter in it.

Also, make sure you always get a dealer fanclutch as the aftermarket ones are thicker....20/20 ehh.

Fergie

Very Cool. No pun intended.

[FUNKYTEE5]

Well, just drove home in +100* weather in stop and go with the AC on.

NEVER WENT ABOVE 215*!! !! !!

I installed a Modine from Napa on Sunday, and have 50/50 mix and a bottle of water wetter in it.

Also, make sure you always get a dealer fanclutch as the aftermarket ones are thicker....20/20 ehh.

Fergie

2 Row? I'm looking to purchase one myself.:)

[Fergie]

Yes, it is a 2-row.

And the shop guy at the rad repair place told me that the Modines were better units in general, as he was handing me a patched CSF.

Fergie

[robs]

Also, make sure you always get a dealer fanclutch as the aftermarket ones are thicker....20/20 ehh.

Fergie

Yeah... 20/20 for sure... *sigh*...

http://www.sija.org/robs/fan1.jpg

[Fergie]

A small update:

Driving home with the AC on, it runs between 210-220. It only hits the 220 when I stop at a light or in traffic, but it cools back down quickly to 210.

Today, I decided to run without the AC on, and the gauge actually went below 210! Amazing to me. the only time it went above the 210 mark was when I stopped in traffic, and the the fan came on and cooled the vehicle off again.

Tomorrow I go in to have the rad sniffed, just to make sure.

Fergie

PS- Anyone have any advice on a seperate coolant gauge, one that is accurate?

[BIGWOODY]

I have an 89 that has had the cooling demons for quite a while now. With the differences in cooling systems it really seems that these problems should not cross over from one system to the other (open or closed). I think from my experiences that the blocks might actually decompose over time and produce sedement that flows through the cooling system clogging up passages, the smaller they are the easier they clog. The stock radiators and many aftermarket radiators have very small passages, adding more rows actually means smaller passages, not larger. I haven't really found a solution but have kept my demons at bay by doing a open system conversion and routine system backflushing.


You sir, have nailed it. I've taken apart many of these with unresolved cooling issues and found exactly what your speaking of. Why this rings soooo true is, IF your STOCK cooling sytem is in good working order and your gear ratio is anywhere near close for your tire size, it works flawlessly with a fresh motor. There isn't a need for bigass aluminum radiators and lower thermostats these may hide the problem or help it out a little, but it still isn't RIGHT! Yes, a tranny cooler is a good idea regaurdless of the condition of the motor. I've seen unreal differences in the temp in mine, it never hits 210 even with whaling on an obstacle for 10 minutes or so matting the gas. Before,about 3 minutes worth of hard "beating on it" it had to sit and cool down or I had to take it easy on it. I still stare at my temp gauge like a freak cause I'm so used to doing it.

[Fergie]

Took the Jeep to have it sniffed today, and the HG is good.

Everything seems to work just fine now.

All I have to do is figure out a way to get an accurate engine temp reading....maybe an aux gauge or something of the sort.

Fergie

[ryurabbit]

Have you checked the cat converter? I have had the overhating issues and both times its been the cat converter. I keep breaking them inside and they restrict the exhaust. Funny thing is that I only lost performance on the first one but the second one never even gave me a clue IT JUST GOT HOT!!!

[JEONLYEP]

I still stare at my temp gauge like a freak cause I'm so used to doing it.
Okay now that made me laugh out load. I know what you mean. Before I owned an XJ I never paid any mind to gauges. Now I can't go a tenth of a mile without looking there. :laugh3:

Going to check mine today to see if it's a head gasket leak or not. If it's not a leaky HG. then I'm going modine or CFS. But something got to change, because my 3 row GDI has been very disapointing.

Daryl

[badron]

[QUOTE=AJsArmor]I think it's incredibly STUPID of all car manufacturers not to have a transmission temp gauge as standard equipment. Otherwise a lot of people, including qualified mechanics will chase what they think is a cooling problem for weeks when in fact it's the transmission that is the culprit. Install a trans temp gauge, they're cheap and worth every penny. I'd also disconnect it from the radiator, run it on it's own cooler to take the load off the radiator.

[badron]

I just don't even know were to start on this reply.
--------------------------------------------------------------
mechanics will chase what they think is a cooling problem for weeks when in fact it's the transmission that is the culprit.
----------------------------------------------------------------
You must know some piss poor mec then

--------------------------------------------------------
think it's incredibly STUPID of all car manufacturers not to have a transmission temp gauge as standard equipment.
----------------------------------------------------------

Half the people on here don't know how to intrepid the water temp gauge!
God put a trany gauge in and there little brains would melt down long before there trany would. Trying to process all this extra information.
Few people even look at the gauges until some dummy light tells them they are FXXKED. So just to get out there wallet and hand it and there first born male child over.
FACT: A good stock rad in front of a GOOD running engine is more rad than 99.99% of you will ever need.
FACT 99.99 of the aux trany cooler are not needed, poorly placed and sometimes even hinder the total cooling of the engine/trany.
I could go on and on and on.
Please band me please.

[JEONLYEP]

Please band me please.

http://users.ucom.net/~werwe/smileyband.gif :party:

Your welcome

Daryl

[Fergie]

Okay now that made me laugh out load. I know what you mean. Before I owned an XJ I never paid any mind to gauges. Now I can't go a tenth of a mile without looking there. :laugh3:

Going to check mine today to see if it's a head gasket leak or not. If it's not a leaky HG. then I'm going modine or CFS. But something got to change, because my 3 row GDI has been very disapointing.

Daryl
ONLY- I will have a new CSF for sale cheap pretty soon. NIB.

PM me if interested.

Fergie

PS- I'd go Modine

[CJR]

Robs,

I had a similar mysterious overheating problem with my 88 Cherokee 4.0 L. The car was still under warranty and I took it back to the car dealer who pressure tested the coolant system and found nothing wrong. I checked the coolant for oil, etc. but could find no indications of a leaking head gasket. Then one very hot day, I saw a very small puff of white smoke come out of the exhaust which only lasted momentarily. I took it back to the dealer that same hot day, and sure enough they finally found an intermittant head gasket leak. Apparently, when it got hot enough the coolant pressure would lift the head slightly to vaporize some coolant and then the head would reseal itself. The head was acting like a relief valve that would blow off some coolant and then reseal. This was really wierd. Anyway the solution was to remove the head, resurface it, replace it with new gaskets and the problem went away. Thankfully, the dealer had to make this repair. You may have the same problem.

When I do head jobs, I like to use the old hot rodders trick of using aluminum paint (stove pipe paint). I clean the head and block surfaces and then start spraying the surfaces with GumOut and wiping them clean with paper towels. I keep doing this until the paper towel stays clean. Then I know the surfaces are clean. I then coat the head, block, and gasket with about three coats of aluminum paint. After the paint dries, I assemble the head to the block and torque it down. I fire the engine and bring it up to operating temperature and then shut it down. Then I retorque the heads and they stayed torqued.

Hope this helps. Good luck!

Best regards,


CJR