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Old Jan 7, 2004 | 09:34 AM
  #1  
isaul's Avatar
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From: Cd. Juarez Mexico
problem overheating

i replace my thermostat this is permanently open and i replace but i put newone and the temperatures is ok but i drive out and the temperature up and up, in the last time never overheating, if you know what happend pleas tell me. tanks. sorry my english is bad.
Old Jan 7, 2004 | 10:16 AM
  #2  
drnovascotia's Avatar
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From: Concord, NH
lemme re-type my overheating FAQ and i'll post it in an hour.

Dr.
Old Jan 7, 2004 | 10:56 AM
  #3  
drnovascotia's Avatar
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From: Concord, NH
here you go. Once I get another mod to edit it, i'm gonna put it in the FAQ Section.
----------------------------
Overheating Walkthrough
First things first, you have to find out what the problem is. Searching would definitely find you the most answers, but i'll try and provide as many as I can.

First thing to try is seeing if you have an air bubble. The Following Paragraph is the procedure to do a PROPER bleed of the coolant. This is the cause of most people's overheating. FIRST do this, and if it does not fix the problem, proceed through the following steps to find your problem.
Bleed The Air:
1. Either jack up the front end or put the car facing up on a hill.
2. Start up the car and let it warm up so it's @ operating temperature, PUT THE HEAT ON FULL.
3. open the radiator cap, and loosen the bleeder screw. This screw is located above the intake, it's a 10MM and has some Japanese writing beside it.
4. Open the bleeder screw, and pour 50% coolant 50% water Mix into the radiator cap, and watch as air bubbles pour out of the bleeder screw. Fill the cap as much as you see the fluid coming out.
5. Squeeze all of the hoses, push them up and down a bit, but mainly squeeze them to make sure you get all of the air out of them.
5. After keep doing this until you get only coolant out of the bleeder screw, no air at all.
6. Close the bleeder screw, top off and close the radiator cap, and you're done!

Other Reasons For Overheating
Radiator Cap/Thermostat – the thermostat should be one of the first things you check after bleeding the air and flush the system. To check if it is working properly, but it in boiling water and see at what temperature it opens. If it doesn’t open properly or at all, replace it. As well, many people find that replacing the radiator cap fixed their problem. One person in particular who had an overheating problem for 6 months found out his radiator cap was defective and causing the coolant to shoot into the overflow tank. Both these are inexpensive and should be looking into before the bigger things. Installing the thermostat is easy, refer to a chiltons or FSM, or email me for more details. The radiator cap is even easier, pop off the old cap and put on the new one.
Cracks in the Hoses/Radiator. Is your car leaking coolant? If your hoses are cracked or the radiator is cracked you will be leaking coolant and losing pressure as well as letting air in. Inspect the radiator with a flashlight as well as the hoses and look for any cracks or signs of coolant.

Water pump. The water pump is attached to that huge fan that circulates when your car is running. If you look closely, there are 2 small holes in the pump itself, one facing up and one facing down. Check for any signs of water leaking through these. If there is any water leaking, the water pump is bad and will need to be replaced. This is a $40 part and will require only a hours work.

Fans - is the fan attached to the belts running? What about the fan attached to the radiator? This is the A/C fan, it also goes on to help cool the temperature. This could well be the problem. See if it is running, if not then you could simply need it replaced. If you cannot see if it is running, then remove the intake, unplug the fans connector (located beside the battery, trace the wires from the fan to the connection and run wires from the ends to the battery. If it starts going then you know the fan itself works. However it could not be working, so make sure to check your fuses as well.
Radiator - Sometime you've been driving for a while and it's warm, check the lower radiator hose when you turn it off. The top hose should be almost too hot to touch, and the bottom one (it leads into the thermostat, consult a Chilton’s or fsm). The bottom one shouldn't be as hot, however you should feel some warmth. If it isn't warm, then it's most likely your radiator (that’s what my problem ended up being after hours of work and replacing parts). If it's not the radiator, proceed to the next possibility. Before replacing the radiator, use a flush kit a couple times and flush out the radiator to see if it is just some clogging.

Head Gasket - Does your temperature gauge go over half ? if so then your car might have overheated and the head gasket might be blown. Next time you drive for an extended period of time, keep an eye on the temperature gauage.
To See if it's your head gasket going bad, do this.
When the car is cold, open the radiator cap and turn on the car. If radiator fluid shoots out then your head gasket is bad. As well, you will find oil in the coolant, which would also show a bad head gasket.

Any questions or problems let me know.

DrNoVaScotia@comcast.net

--------------------------
Dr.
Old Jan 8, 2004 | 05:14 PM
  #4  
devnull's Avatar
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Joined: Dec 2003
Posts: 265
Is this in the FAQ yet...because it should be.
Nice work doc.
Old Jan 8, 2004 | 05:40 PM
  #5  
drnovascotia's Avatar
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Joined: Feb 2003
Posts: 1,854
From: Concord, NH
no, i'm gonna copy and paste it in the FAQ's right now, I wanted hyjnx to check it out first, before I did so for any inputs.


Dr.
Old Feb 6, 2005 | 03:28 PM
  #6  
kang128's Avatar
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Joined: Oct 2004
Posts: 110
From: 718
is there supposed to be steam coming out of the bleeder screw??...cuz thats whats happening to me
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