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Old Feb 12, 2010 | 03:40 AM
  #41  
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ok use the top tube that goes into the throttle body and back into the radiator, diconnect that hose since its the highest point of the cooling system, open the radiator petcock and turn the heater on and put the garden hose in the radiator and force water in there to relieve the air pockets. this is very weird i never seen it this hard to bleed the cooling system hopefully its just an air pocket.
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Old Feb 20, 2010 | 10:06 AM
  #42  
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well i flushed the **** out of her for a good 30-45mins. First i flushed it with the engine not running. I had alot of crud and sandy looking **** coming out of the petcock of the radiator. Then I flushed it with the engine running. No weird stuff came out this time and it stayed completely cool while being flushed. I cut off the water supply and kept running and it managed to keep itself cool but it was running hotter than it should with a 160 t-stat.(180-190) Drained as much water out as i could and started putting coolant in it. still ran at about the same temp. When I was filling it up with coolant it took it all in really fast but then it would shoot up back into the funnel then go back down again. when it went down again, i put the rad cap back on. So i drove it around for a bit and ended having to drive it to work because i didnt have to time to switch cars. On the way back from work it started overheating again. I have not had much time to mess with it since then. I noticed that the coolant was almost overflowing out of the overflow tank and the hoses were very hard and looked like they were bulging a little bit. now im starting to think that maybe my radiator is just shot now. that would explain why its running hotter than it should.
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Old Feb 20, 2010 | 11:52 AM
  #43  
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it probably just pushed more **** through. there is a 2-part chemical flush you can buy at auto parts store. works pretty good.
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Old Feb 20, 2010 | 01:11 PM
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also want to add that when i was driving, I would start to slow down to a stop and the temp would go up to 210 pretty quick then cool back down to 180-190 once i got moving again. It never did this before. it always ran cooler and stayed at the exact same temp no matter what.
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Old Feb 20, 2010 | 07:14 PM
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coolant is just sitting still in the radiator, just as everything was before I flushed it.
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Old Mar 3, 2010 | 03:08 PM
  #46  
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I pulled the radiator to see if it was clogged up or anything. I ran water through it with the garden hose and it came out clear and easy through the other side. Im probably going to replace the radiator anyway just because it looks kind of beat up and its old. This is driving me nuts, I need to get this figured out before spring.
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Old Mar 3, 2010 | 04:34 PM
  #47  
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sounds like a head gasket to me, or a head itself, or even a cylinder wall
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Old Mar 3, 2010 | 05:00 PM
  #48  
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my buddies jeep was the same way.

had this nasy *** **** in the radiator, but the oil and everything looked good. turned out to be a cracked head. anybody that knows anything about 4.0 jeeps knows cracked heads.
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Old Mar 4, 2010 | 08:03 AM
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Originally Posted by MasterSe7en
sounds like a head gasket to me, or a head itself, or even a cylinder wall
Could you explain how it could be a cracked head or cylinder wall. How exactly can I tell? I pulled the valve covers and everything looked fine, no cracks or anything that I could tell.
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Old Mar 4, 2010 | 05:31 PM
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Ok is the elec fan working?
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Old Mar 4, 2010 | 07:35 PM
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Like I said earlier....PRESSURE TEST your cooling system. This will most likely tell you what is going on.

If that checks out then pull the radiator and have it flow tested at a shop to see if it is clogged. Sometime you can tell by doing it yourself if it is clogged really bad by just pulling the bottom hose and watching how fast it drains out with the cap off....
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Old Mar 4, 2010 | 09:36 PM
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Originally Posted by bjamick
Ok is the elec fan working?
yes it is working.

Originally Posted by SOMbitch
Like I said earlier....PRESSURE TEST your cooling system. This will most likely tell you what is going on.

If that checks out then pull the radiator and have it flow tested at a shop to see if it is clogged. Sometime you can tell by doing it yourself if it is clogged really bad by just pulling the bottom hose and watching how fast it drains out with the cap off....
Only reason I havn't done this is because I dont have a cooling system pressure test kit which is pretty expensive and i dont have access to one either.

I tried swapping radiator caps and pulling the coolant air bleed pipes. still overheating but i noticed that it did not overheat as quickly as it did before.
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Old Mar 4, 2010 | 09:50 PM
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Originally Posted by gmmusclecarman
yes it is working.



Only reason I havn't done this is because I dont have a cooling system pressure test kit which is pretty expensive and i dont have access to one either.
I tried swapping radiator caps and pulling the coolant air bleed pipes. still overheating but i noticed that it did not overheat as quickly as it did before.

I bet a shop would do it real cheap. It takes maybe 2 minutes to put it on and pump it up and then just wait and watch.

Maybe you can rent one from AZ or Advance or somewhere...
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Old Mar 5, 2010 | 06:12 AM
  #54  
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I have similar issue, I found one of the bolts holding the water pump to the block is loose and the water temperature sesor need repalcment
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Old Mar 5, 2010 | 10:02 PM
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Replace the radiator cap.
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Old Mar 11, 2010 | 09:45 AM
  #56  
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Well guys I finally fixed this last week. I tried pulling the coolant air bleed pipes again except this time I let it heat up to 210 with everything closed up. As soon as I did this it cooled off to just over 160 which is right where it should be. Been running it for a week or so now with no trouble at all. Weird cause I tried this a couple times in the first place and it didn't seem to do anything.
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Old Mar 11, 2010 | 10:35 AM
  #57  
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Good deal man glad all it all worked out for you. It usually is the simple stuff that kick you in the behind.
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