Overheating issues!!

[02SilverGT]

Ok have a 92 LX. I bought the car from a friend. I have replaced both HG, replaced lifters, pushrods, thermostat. He told me the car would overheat so I replaced everything I thought would need to be replaced to correct the situation. Here are some symptoms.

Car starts up fine. Idles fine. I can drive the car for about 3 miles, when all of a sudden the temperature will climb straight up FAST.
If I keep the car idle it doesnt ever climb that fast. I beleive the WP is fine because as I stated it runs fine idling but under load it climbs.

Now I am also leaking water around the EGR spacer, not sure why but any help would be appreciated.

I have a question about the thermostat. Does the thermostat go in the Intake or does the "spring" go in the thermostat housing.

I have drained the and flushed the coolant several times however when it overheats the water comes out real rusty color. Any help?


I did a search and I see alot of "air Bubbles" listed as a possible cause. Please tell me how I can correct the situation.

Thanks again.

Stefan

 

[TheUser]

First thing is the stock guage is sometimes wrong, so some guys won't even try to help you if you're using the stock guage since accuracy might be an issue. Is the coolant boiling over?

That being said, I am not one of those guys Your spring on your thermostat goes IN the intake; the reason is there is wax there that melts when the car gets up to temp, the spring allows the thermostat to open and coolant flows to the radiator which is air cooled and sent back through your system. If your spring is any other way than inside the intake, change it.

Secondly, if you have a bunch of rust, that isn't necessarily the best thing. Ideally, you'd want to dump your coolant and stick a hose in the radiator and let it run until that crap gets out. I pulled my radiator and did this since the thermostat would have prevented it from going through the motor. Additionally, I reinstalled the radiator and filled it up with water only. I drove it a few minutes until it got up to temp so the thermostat opened and water flowed through. I went home, let it cool down and dumped the coolant. I re-did this until the water I dumped out was clean Then I added my coolant/distilled water combo. That's right, distilled water. My GT has no "tap" water in it. The reason it has minerals in it and some say it corrodes the cooling system. My Jeep and LX 5.0 run with tap water and anti-freeze, however. You do want to run at least 50% anti-freeze though. Not only does it prevent freezing, it also raises the boiling point of the water.

Anyway, once you fill it up, leave it about 6 inches below the radiator neck. Raise the front of the car so that the thermostat housing is higher than the motor. I guess this helps get the bubbles out. HISSIN says do it, so I do Let your car idle until it gets up to temp and you'll see air-bubbles pop out here and there. Once the air bubbles stop, you can top it off and put your cap on. If at any time throughout this procedure, your coolant level drops way down in the radiator (most likely when the thermostat opens that will happen), fill it up to 6 inches below the neck right then and wait for any other bubbles to come out.

Lastly, you need to make sure your radiator cap fits snugly on your radiator. If you hear any "hissing" or air coming out of the cap, replace it.

Good Luck

EDIT: if this is happening at highway speeds, your radiator might be suspect. Your fan seems to be ok since you're fine at idle. If you do all of the above and still have the problem, I'd suspect either the radiator and/or misleading/inaccurate temperature guage.

 

[sgarlic]

When the car is cold, and you turn the ignition on, where does the temperature gauge fall? If it's like my last set of gauges (right in the middle,) then maybe you're actually at an ok temperature, but the gauge is way off.

If it's not the gauge, I would think, that if you heat up fast only when driving but not idling, that either your thermostat is stuck closed, or you have some major blockage issues in your rad preventing the water from flowing through fast enough when it needs to flow through fast (higher rpm.)

 

[d50man]

Hey!

did you buy a new temp sender its a $5 part and it adds accuracy to the guage.
i also rust in my car was heater core, good luck

 

[HISSIN50]

James, i might have mistyped at some point, but actually you want the radiator neck to be the highest point in the system (the stat does not matter, though it helps if it came with a bleed hole). i jack the driver front up a little to accomplish this.

you will want to either replace the gasket that leaks or temporarily bridge together the two coolant lines to the EGR. I am not a fan of keeping the lines connected like this if you still have a functional EGR, but people do it.

i agree 100% about the gauge. i have an extra turkey/confection thermometer (for shop use only!) that i use to check temps in the radiator. it is hard to interpolate the stock gauge, but you can try to see if it is vaguely calibrated or not by using the turkey thermometer.

However, while i also try to help people who may have nothing more than a bad gauge/gauge sender, it can really be misleading to make diagnoses with said gauge. i am a huge fan of aftermarket gauges (i have 5 in the 88 GT vert and 4 in the 94GT).

running hot at speed can be poor heat transfer in the radiator (like what SGarlic was getting at). the coil simply cant reject heat fast enough.

good luck.

 

[TheUser]

James, i might have mistyped at some point, but actually you want the radiator neck to be the highest point in the system (the stat does not matter, though it helps if it came with a bleed hole). i jack the driver front up a little to accomplish this.

HISSIN: No, I think you probably typed correctly, but I most likely mis-read what you typed. I always wondered why you wanted the "thermo-housing" higher than the rest and it made absolutely no sense, but I did it all this time because my mis-interpretation made me think you recommended it. I searched and re-read a post or two of yours about cooling issues and you did indeed type the radiator neck. It makes sense and now I got it Sorry for the mis-information 02SilverGT

 

[HISSIN50]

HISSIN: No, I think you probably typed correctly, but I most likely mis-read what you typed.

BTW, it is still probably my fault. I toss out thoughts quickly and randomly - I know my posts are hard to follow.

 

[5.0 coup]

that is your problem you are leaking at your egr when ever you hav a leak you will over heat thanks Leo. mustang coup

 

[TheUser]

that is your problem you are leaking at your egr when ever you hav a leak you will over heat thanks Leo. mustang coup

leaks definately aren't good and should be fixed ASAP, but that leak might not necessarily be the complete cause of the overheating, although it might be contributing. Depending on the length of time this has been leaking and if you check your cooalnt level regularly, you probably wouldn't lose enough coolant from that little hose (unless the whole hose is off or something) to cause overheating...that's just my opinion.

Fix the leak none-the-less

 

[HISSIN50]

agreed with James. half the cars on the road today have a coolant leak of some sort. every PSI in the cooling system roughly equates to an increase of 3*F in the boiling point. a car with no pressure should be alright a little ways past boiling as it is. and a small leak wont drop pressure that much.