Here's a picture of my Jeep with no cooling fan or shroud. Never overheats! Before I replaced everything I'd start with a flush to keep it cheap. Thermostats are cheap I'd move on to that next. If you live in a very hot climate getting the electric fan running would be good if you use the AC a lot. Does it only overheat when you use the AC?

 

hi mike thanks for your input i live in scotland so air con dont get much use lol. when i switch the aircon on nothing happen due to the fact there is no gas in the system so it wont go on if i jumper the presure switch on the aircon then turn it on it will work ie. fan will come on today i replaced the sensor on the thermostat housing and the radiator as the old rad was not the best. but still getting hot in start stop driving, got home and had the idea to plug the old sensor in to the loom without it being in the housing and blast it with gas torch what do you know the fan came on why is it not working when in housing i really dont wont to wire a switch to the fan as i am fussy and know it must be something simple ohhhh my head hurts helllllllllllllpppppppppppppp ps crysler uk took £60 for a temp sensor nobody else here carrys one yes thats about 100 bucks to you guys

 

If I don't even need the fan in a similar temperature zone, it makes me wonder why you would need yours? That leads me to believe there is a blockage in the cooling system. You can do this incrementally. Take the two hoses off that go to the Heater core. Remove the ends near the thermostat of course...
Then stick a garden hose in the hose that comes off the thermostat housing. This pushes the rust and junk out of the shorter hose which you route to the ground. Then I pumped water through the shorter hose. You may find that your heater works better after this also. Mine did. I drove it one day and then did this again. More rust came out. I did it until no moree rust came out. 3 or 4 times... This way you don't have to pull the radiator hoses. Kind of a lazy mans way to do it. Not as effective but it works. If it still runs hot then you may have to spend a few bucks on a radiator or get the fan working... But I really think the fan not working is a symptom not the disease.

 

i will try flushing the heater but i have a very good heat from it what leads me to think its fine the hose going from my thermostat to the heater has a t piece splitting it to heat my propane (lpg over here)regulator

 

ps. i have changed the rad mike

 

When your flushing the heater core out and then driving you are allowing it to work as a filter to get the crud out. Like I said it's not as good as a real flush but it worked for me. I like trying the simple easy, cheap solutions first. And spending more time tracing the exact problem before I start spemnding money. Are you going to concentrate on the fan then? I had an old truck that when I started to run hot I could turn the heater fan on and it would get her back into range. That lead me to figuring the radiator was not so good. That's back in the college days so I had to be creative before I could put the cash together for a radiator. But that experiment of turning the heater on high made lead me to a flow issue and then the radiator... After a flush didn't do it. The radiator shop could test your radiator for flow...

 

i will flush the heater core in the morning but im sure i got most of the crud out when i changed the rad this morning maybe my fan clutch is not the best and need a help from the other one but it is normal to need the second fan thats why its there i think or they would have just put the one in the middle and centered the ac rad

 

But in the USA the second fan is always utilized when the AC is on or the motor has a high cooling demand placed upon it. Other than that it doesn't fire much.
So... where does that leave us? You have good heat out of you heater so that is not plugged. Flushing won't help that...
Question Do you think theree might be air in the system? Does the needle on the temp gage fluctuate more than before? That might be another cheap test. Hopefully I won't be lambasted by others here but I must ask if you are comfortable and know the correct way to pull the radiator cap off while the engine is running? That can let any air out. Please don't try this if you don't know how!
Another question... if you pull the radiator cap while the Jeep is cold is it full? Did the Jeep suck radiator fluid out of the overflow tank since you've been driving it?
Do you have a friend with a good radiator cap you could borrow for a day to eliminate that? If it didn't pull coolant out of the overflow maybe the cap is bad...

 

i did tyr to burp the system with the cap of when i refille d the rad and got alot of air come out rad cap new with rad so no probs there going to pull the stat and change that also they are cheap anyway

 

Sounds good. Fix the cheap stuff first... I just wonder about the cap after that. I think you said something about coolant leaking out in one of your first posts. To me that would seem like a possible cap issue. You know how they get corrosion underneath the caps? I wonder if a cleaning of those surfaces might allow the cap to seal tighter and allow the system to carry more pressure thus eliminating your issues...

 

how much of a difference would the lack of anti freeze in the system make as i have been working on it i havent bothered putting any in as it might be wasted if i had to drain again

 

They are made to run full. You could damage your Jeep depending on how low it is. It's not worth taking a chance. Antifreeze is cheap you ought to go get some and fill it up right away!

 

thats not what i mean mike i have it full but just with water no anti freeze i have six litres in the garage ready to replace half the water what i was wondering is maybe the anti has cooling properties

 

Water boils at 212F. If you add antifreeze the boiling point goes up higher. So with our Jeeps that run around 210 you are boiling the water in your engine. Better not do that! Are you any closer to fixing your problem? What else have you tried? Have you been driving it around with just water in there. Whatever you do don't crack the cap when it's hot! That water is most likely boiling and will burn you.

 

um not been boiling yet as water does not boil at 212 (100c)when under pressure but i have been reading that the fan switch might not operate with plain water as for the very reason of the antifreeze allowing the temp to be higher without boiling i will change the water out for antifreeze now.i have hard wired the fan to a switch on the dash for just now as i have ordered i new temp switch from a company in the states who can supplie it shipped at a fraction of the cost from uk dealers