That was my problem and I'm still kind of scratching my head on it. :wierd:
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Long battle with overheating 96 XJ.
- Thread starter heisenberg
- Start date
That was my problem and I'm still kind of scratching my head on it. :wierd:
- Location
- MilkyWay Galaxy
Be warned that welding the exh-manifold can warp the face structure, flange mounting area during welding!!! Might want to look at ways to avoid that, like bolting it to a thick, rigid flat plate before welding, and using a cooler welding method (not stick, but wire....), and if it warps,you can not just sand it flat-parallel as it needs to have the same thickness as the intake manifold for the bolts to keep them both sealed!!!! The bolts overlap the two!!!!
I ended up having to use copper shims to get mine sealed and flat on all the ports after welding the cracks.
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91AzXJ
NAXJA Forum User
- Location
- Phoenix, Arizona
If you drive it on the highway does it heat up? When you stop and turn it off does the temp keep rising? If you answered either of these questions with yes, chances are your radiator is partially stopped up.
heisenberg
NAXJA Forum User
- Location
- Colorado Springs, CO
the radiator is brand New.
streetxj
NAXJA Forum User
- Location
- Pembroke Pines, FL
I'm wondering if you are running lean.. I think running lean can cause excessive heat. Also, every stock cherokee I've been in tends to hang around the 210 degree mark after a while during hot weather, especially in heavy traffic areas.
dieselenthusiast
NAXJA Forum User
- Location
- Zuni Mountains, New Mexico
subscribing...
heisenberg
NAXJA Forum User
- Location
- Colorado Springs, CO
I wouldn't care if it hung out at 210, the problem is that it likes to have an affair with the 230
scubamark13
NAXJA Forum User
- Location
- san diego ca
I am having the same issues. How can I check to see if it is running lean?
- Location
- South San Francisco, CA
You need to check your fuel pressure with a gauge. My RENIX runs at 31 PSI at idle, 37 with the vacuum disconnected at the fuel pressure regulator. Check to see what the specs are for your year.
As far as my overheating symptoms, I was fine at idle and around town. I had changed everything (radiator, thermostat, water pump, hoses, did the ZJ fan clutch, flushed it several times due to a crap load of stop leak in the system from the PO). Never broke 200 degrees on my mechanical gauge. As soon as I started climbing a long grade in 80 degree plus heat, my temp would slowly creep up past 230, flirting 240! At Ecomike's suggestion, I checked the down pipe to the collector. It was pretty wasted. I had it replaced and looked at the flange when the exhaust guy pulled it off. The sealing surface was so beat up it wouldn't seal well. Once it was changed out I noticed a HUGE difference in temps. On the way to Sierrafest it was over 100 degrees in the valley. Climbing the long, steady grade up the hill I topped out at 218 degrees with a full load of camping gear and spare stuff for the Jeep.
- Location
- MilkyWay Galaxy
:greensmok
Mine was a bad donut, beat up sealing surface on the donut, had been reused way too many times. Damn $2 part, LOL!
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- Location
- MilkyWay Galaxy
Pull the spark plugs, rich is black and lean is burned. See the color charts:
http://kakimotodotcom.blogspot.com/2009/10/spark-plug-diagnosis-chart.html
heisenberg
NAXJA Forum User
- Location
- Colorado Springs, CO
Just wanted to give an update:
Tomorrow I'm replacing head gasket, and the cylinder head with a reman, and also putting on a new exhaust manifold.. I'll let y'all know what happens.
Tomorrow I'm replacing head gasket, and the cylinder head with a reman, and also putting on a new exhaust manifold.. I'll let y'all know what happens.
I had an over heating prob with my 96 and replaced the same parts you have and come to find out the crank sensor failed so I replaced that and havent had an overheat since??????? Im no expert but can a crank sensor CAUSE an engine to run lean due to inaccurate signal to the ecm??? Either way it fixed the overheat on my rig. Ive since pulled a trailer with atvs in 110 degree heat with out an issue...
- Location
- MilkyWay Galaxy
I have serious doubts about that one. Bad CPS usually just causes it die and eventually it wont start.
heisenberg
NAXJA Forum User
- Location
- Colorado Springs, CO
Well I'm back as promised.
So I replaced the cylinder head, head gasket, and exhaust manifold.
The head gasket fell apart when the head came off, and the exhaust manifold was slightly cracked near the flange.
I have been driving the Jeep since yesterday and it runs COOL now doesnt even hint at overheating. So moral of the story is even if there are no signs of a head problem there still could be a problem. I had no symptoms of head problem besides overheating and doing a head job fixed my problem!
Thanks for all your help!
So I replaced the cylinder head, head gasket, and exhaust manifold.
The head gasket fell apart when the head came off, and the exhaust manifold was slightly cracked near the flange.
I have been driving the Jeep since yesterday and it runs COOL now doesnt even hint at overheating. So moral of the story is even if there are no signs of a head problem there still could be a problem. I had no symptoms of head problem besides overheating and doing a head job fixed my problem!
Thanks for all your help!
- Location
- MilkyWay Galaxy
Cool! :laugh:
Thanks for the closing report!
Thanks for the closing report!
heisenberg
NAXJA Forum User
- Location
- Colorado Springs, CO
OH, I almost forgot!
The upper radiator hose still gets really hard!! But its not as hot as it used to get.
The upper radiator hose still gets really hard!! But its not as hot as it used to get.
The flange on my exhaust manifold was leaking and causing my xj to overheat. It was blowing hot exhaust directly over the freezer plugs, where the metal is thin and the water jacket is vulnerable. It even caused the plug to leak! I tried everything, new water pump, fan clutch, thermostat, almost bought a new radiator too! Then I discovered the leak in the exhaust manifold hitting the freezer plug. I tightened the loose flange bolts and, voila! No more overheating! Who would have thought? Yes, hot exhaust hitting the side of your engine block directly can make your engine overheat!
