Calling all stock Jeep Cherokees, 97+

[Mudderoy]

As many of you know I've been fighting a running hot on the freeway problem since I lifted my XJ. I have a 1998. I have completely redone the engine cooling system, with the exception of the heater core. I bypassed that just to see if it was the problem (long shot) but it didn't so it's back in line now.

This 3 year journey has brought me to another possibility. We all know that air flow is the culprit when over heating occurs at highway speeds, so since the fan and clutch, belt is tight, etc... it must be that enough air isn't being forced through the radiator.

This is a borderline problem. With the A/C off the cooling system runs quite close to the 210 mark at highway speeds. Discussions here and searching and reading information on the Internet had made me consider that it might be the lack of an air dam.

Keep in mind that after I lifted the Jeep, 7", it started to run hot. I addressed the additional effort on the transmission with a cooler, perhaps a small change, but not a solution.

Since I have removed my front bumper and replaced it with a custom I no longer have the reference point that I need to determine how low the air dam should be.

I was wondering if someone with a stock 97+ XJ could take a head on picture of your rig and post it. Also could you measure the distance from the ground to the bottom of the front bumper in the center of the front?

I'd like to have a 97+ so I can have as close to my original configuration as possible.

I was going to build a sheild to protect the alternator from water and mud anyway so this will be good from the stand point of possibly solving another problem.

The idea is that an air dam will create a negative pressure in the engine compartment and draw more air through the radiator.

[bluedragon436]

Now when you say you want a measurement from the ground to the bottom of the bumper...are you meaning the bottom of the actual bumper, or the bottom of the air dam?? The reason I ask is because I know some people don't have the air dam, some do?? And for the head on pic, you want it from normal standing level, or the camera more down on level with the bumper height??

[Mudderoy]

Now when you say you want a measurement from the ground to the bottom of the bumper...are you meaning the bottom of the actual bumper, or the bottom of the air dam?? The reason I ask is because I know some people don't have the air dam, some do?? And for the head on pic, you want it from normal standing level, or the camera more down on level with the bumper height??

Well maybe I need to check my facts. I thought all the 97+ had the molded bumpers like my 98 did. The only way to remove the dam would be to cut it off or remove the factory bumper.

To answer your question directly, to the bottom of the air dam.

http://xjtalk.com/images/special/Jeep_Photoshoot3.jpg

Ok looking at my own picture, I guess it is possible to remove that center piece just below the bumper. Not sure why anyone would and leave the aread with the fog lights...

[Mudderoy]

Well my answer may have been as easy as looking for a picture online! :smiley-laughing021:

http://www.edmunds.com/pictures/VEHICLE/1997/Jeep/13145/1997.jeep.cherokee.5990-E.jpg

But a measurement would be best...

[bluedragon436]

I was thinking about grabbing a pic online... l

[Mudderoy]

So looking at that picture, I am wondering if the air dam need to be from wheel to wheel or just the bit under the radiator area...

[XJ Rat]

Just an idea...have you checked the timing?

[prerunner1982]

Timing should be done by the ECU so it is not adjustable.. unless the distributor is not set right.

Tony... I think you would be ok with the air damn only going as wide as the radiator.. any wider than that and it is in front of the wheels, which would not cause any difference in air flow in the engine compartment.

[XJ Rat]

My 98 measures 22 inches from the ground to the bottom of the air dam and 26 inches from the ground to the bottom of the bumper. I have a RE 3-1/2" lift and 3/4" spacers in front and extended shackles in the rear along with 32" Swamper tires.

I would still check the initial timing as I have seen more than one car overheat because of timing issues. What could it hurt seeings as you have already done so much to your Jeep.

[Mudderoy]

My 98 measures 22 inches from the ground to the bottom of the air dam and 26 inches from the ground to the bottom of the bumper. I have a RE 3-1/2" lift and 3/4" spacers in front and extended shackles in the rear along with 32" Swamper tires.

I would still check the initial timing as I have seen more than one car overheat because of timing issues. What could it hurt seeings as you have already done so much to your Jeep.

I spoke to a mechanic friend of mine about that and he said it was all handled by the ECU. If it was 20 years ago it would be easy, now, from what I can tell it would be changing all the time.

I'll look into how to check it. Seems like I remember something about setting the base timing, but you basically have to stop the ECU from doing the timing advance. I'm thinking it would get pretty upset, and frankly I don't see how the engine would run without it.

When I was working on another problem I was able to confirm that the CKS in the distributor was aligned correctly, so I haven't been concerned about the timing since then.

[gary63]

I have a stock 2000 with airdam and bumper still what do you need.
from were to were.

[Mudderoy]

I have a stock 2000 with airdam and bumper still what do you need.
from were to were.

Excellent! Thank you.

I would like to know the distance from the center of the front of your xj between the ground and the bottom of the bumper. The lowest point of the molded bumper. Basically I'm trying to understand just how far off the ground the bottom of a home made air dam would need to be to have it be the same height as the factory air dam.

[XJ Rat]

Also, my 98 gets real warm when sitting in traffic, but cools right down as soon as speeds over 10MPH are reached. New antifreeze, new hoses, new thermostat, complete flush did not help the over heating in traffic. I installed hood vents. They helped a very little bit, more for looks than function. Do not see how people claim 15-20 degree cooler running with these. Yes, they helped, but not that much...just my experience.

No more factory skid, there is nothing behind the OEM bumper/air dam. Except the engine.

[gary63]

Excellent! Thank you.

I would like to know the distance from the center of the front of your xj between the ground and the bottom of the bumper. The lowest point of the molded bumper. Basically I'm trying to understand just how far off the ground the bottom of a home made air dam would need to be to have it be the same height as the factory air dam.
ok I will get it for you in a cupablr hrs when the sun comes up we are still drak and snow and ice but I can get. I will go corner to ground from bumper and airdam and then center. what are you doing about your sides front mud
flaps my drik the air under that is the no flix ones.

[brandonlp]

mudderoy- when did you change the fan clutch last, also you think it has a lack of air flow, hows your a/c condenser looking, if its beat up from rock and filled with dirt and bugs from over the years then you will get a lack of air flow threw it.

i removed mine and upgraded my fan clutch to the zj, and i dont get to 210 unless im wheeling for a period of time in a 90+ degree day,

just a thought, check it unless you already replaced it.

[Mudderoy]

Also, my 98 gets real warm when sitting in traffic, but cools right down as soon as speeds over 10MPH are reached. New antifreeze, new hoses, new thermostat, complete flush did not help the over heating in traffic. I installed hood vents. They helped a very little bit, more for looks than function. Do not see how people claim 15-20 degree cooler running with these. Yes, they helped, but not that much...just my experience.

No more factory skid, there is nothing behind the OEM bumper/air dam. Except the engine.

Try the Heavy duty grand cherokee clutch fan from NAPA. It's about $40 and very easy to put on. You might want to get an accurate MPG before swapping this. I bet that you'll see a big low speed difference in your engine cooling system.

The next thing I would do would be the high flow thermostat housing and thermostat. After that the flowkooler high flow water pump, about $100 from Summit.

[Mudderoy]

ok I will get it for you in a cupablr hrs when the sun comes up we are still drak and snow and ice but I can get. I will go corner to ground from bumper and airdam and then center. what are you doing about your sides front mud
flaps my drik the air under that is the no flix ones.

Center measurement should be fine. Any thing that I put on the front of the Jeep is only going to be in the center, about the width of the radiator opening.

[Mudderoy]

mudderoy- when did you change the fan clutch last, also you think it has a lack of air flow, hows your a/c condenser looking, if its beat up from rock and filled with dirt and bugs from over the years then you will get a lack of air flow threw it.

i removed mine and upgraded my fan clutch to the zj, and i dont get to 210 unless im wheeling for a period of time in a 90+ degree day,

just a thought, check it unless you already replaced it.

Couple of years ago. I replaced the clutch fan with the grand cherokee heavy duty clutch in an attempt to resolve the running hot issue on the freeway. As I recall it help very little, if at all.

I can wheel in 95+ air temps with A/C full bore, and I don't have any issues. I don't have ANY low speed overheat issues now. :D

One of the things I did was clean the condenser, at home and at the car wash.

[XJ4IV]

As many of you know I've been fighting a running hot on the freeway problem since I lifted my XJ. I have a 1998. I have completely redone the engine cooling system, with the exception of the heater core. I bypassed that just to see if it was the problem (long shot) but it didn't so it's back in line now.

This 3 year journey has brought me to another possibility. We all know that air flow is the culprit when over heating occurs at highway speeds, so since the fan and clutch, belt is tight, etc... it must be that enough air isn't being forced through the radiator.

This is a borderline problem. With the A/C off the cooling system runs quite close to the 210 mark at highway speeds. Discussions here and searching and reading information on the Internet had made me consider that it might be the lack of an air dam.

Keep in mind that after I lifted the Jeep, 7", it started to run hot. I addressed the additional effort on the transmission with a cooler, perhaps a small change, but not a solution.

Since I have removed my front bumper and replaced it with a custom I no longer have the reference point that I need to determine how low the air dam should be.

I was wondering if someone with a stock 97+ XJ could take a head on picture of your rig and post it. Also could you measure the distance from the ground to the bottom of the front bumper in the center of the front?

I'd like to have a 97+ so I can have as close to my original configuration as possible.

I was going to build a sheild to protect the alternator from water and mud anyway so this will be good from the stand point of possibly solving another problem.

The idea is that an air dam will create a negative pressure in the engine compartment and draw more air through the radiator.
orrrr Suction???
Tony likes to use bigger words to throw us off a little.
Sooooo did you get the issue FIXED??

[Mudderoy]

orrrr Suction???
Tony likes to use bigger words to throw us off a little.
Sooooo did you get the issue FIXED??

lol no.