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jeepsterjohn 03-30-2012 05:33 PM

cooling issue
i have an 04 4.7 it has now started to get hot after running only 10 or 15 minutes. It has a new thermostat or so the dealer told me. the fan sounds like its working its a$$ off but its not cooling anything. any other things i need to look for. fan relay, new fan, any ideas would help.

Escape 03-30-2012 05:38 PM

Re: cooling issue
I'd check for air in the cooling system.

01grand 03-30-2012 06:15 PM

Re: cooling issue
Check for air in the system, there is a bleed plug to remove where the upper rad hose connects to the engine, pull it out and make sure the coolant fills up to there. Could also be plugged lines or a block in the radiator.

Frango100 03-30-2012 09:11 PM

Re: cooling issue
The engine gets hot, but is the radiator hot as well? Check the upper radiator hose and feel if its hot. When not, there is probably not (a good) circulation through the radiator. I presume that the thermostat is placed in the right way, otherwise it will not open and the liquid will only circulate through the engine and not even reach the radiator.
When the fan is working its a$$ of, the problem should not be looked for overhere. The 4.7 2004 has a hydraulic fan feature, which uses the fluid from the power steering system. If it runs strong, its ok.
What was the reason that the dealer had changed the thermostat? Did the engine already present problems before and did they change it for that reason?

jeepsterjohn 03-30-2012 10:39 PM

Re: cooling issue
they said they changed it because it had check engine light and said thats what the code popped up. is this possible

01grand 03-30-2012 10:47 PM

Re: cooling issue
There could be a code for high coolant temp from the coolant temp sensor, and a thermostat would be a good place to start, but sounds like they didn't really solve the problem.

Frango100 03-31-2012 08:06 AM

Re: cooling issue
So did you check the upper radiator hose close to the radiator to feel if its hot? If the thermostat is mounted right, there is a change that the waterpump is at fault. It could happen that the impeller is loose from the shaft causing a too low flow or no flow at all. Blocked radiator is possible as well. So start with the simple and check the upper radiator hose. If it doesn´t get really hot but the engine temp is, there is some flow problem. With the engine cold, you can remove the radiator cap and take some liquid out. Now start the engine and let it warm up. The liquid will expand and flow out of the radiator cap, but when the engine is at operating temperature, you should look for flow of the liquid. When its completely standing still, or the thermostat is mounted in the wrong direction and doesn´t open, or the radiator is blocked or the pump is at fault.

jeepsterjohn 03-31-2012 11:36 AM

Re: cooling issue
So far it appears it had air in the system. I dont think at this point they changed the thermostat at all. Ive owned this thing for 2 weeks and already had to replace the plugs, coil, injector, and battery possibly the alternator today. its turning into a money pit

Frango100 03-31-2012 01:13 PM

Re: cooling issue
What is happening to your jeep that you already had to change so many things???

jeepsterjohn 04-01-2012 01:43 PM

Re: cooling issue
The day after i got the jeep it threw a fault code for misfire in cylinder #1 changed the plugs and still had the light, changed the coil the light went out but returned a couple hours later. this all started when i was 200 miles from my home. on the trip home it started to sputter and cut out. at this point the light started flashing at me then stopped and stayed on. got home checked plug looked dirty again cleaned it and changed injector. After that the battery went dead it was older so i bought a new one. after i put it in the voltmeter was kind of weak still its holding a charge so i have not replaced the alternator as of yet.

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