overheating whats ur opinion

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s13ofdoom
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hey i have a 1990 240sx i emptied and refilled my radiator to no prevail. after 15 mins of idoling temp climbs to the top. so my question is too u what have u experienced u think its rad t-stat or fuel pump?? if u could help id really apperciate it


skitzo
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The most common cause of overheating is the radiator cap, make sure its in good working order.

After that make sure the water pump is working and then check the thermostat.

If your car runs rough its probably the head gasket, confirm with a compression check.

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quiksilvia
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do a compression test first, and if that comes up ok then look towards the tstat

bcuz
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I recently was spraying coolant all over my engine bay.. that kinda sucked. my water pump was leaking and the drip went right onto my fan belt.. and then that just spewed it all over :\ ...got that replaced and voila! no more overheating :)

dareo
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Car: 1993 Q45, 1989 240sx

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Mine runs so cool that i think my thermostat is stuck wide open. i gotta do over 100mph in the canyon with the stereo up to get it 1/4 of the way up the gauge. Yet the heater will work well, so i know the motor is sort of warm.

Is there any big issues with running cool all the time? Its just gotta last me till i can pick up a clip.

CanadianCoch
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here. something I posted earlier, this is pretty much everything it could be.

First things first, you have to find out what the problem is. Searching would definately 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. At the end of this essay is the procedure to do a PROPER bleed of the coolant. This is the cause of most people've overheating. FIRST do this, and if it does not fix the problem, proceed through the following steps to find your problem.

1. Does your temperature gauge go over half when the coolant is bullbing? 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 gausge.To See if it's your headgasket 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.

2. 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 ino the thermostat, consult a chiltons 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 (thats what my problem ended up being after hours of work and replacing parts). If it's not the radiator, proceed to the next possibility.

3. 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 (loacted 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. Hovever it could not be working, so make sure to check your fuses as well.

4. 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.

5. Check your 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.

6. If it's not the radiator or Head Gasket or water pump, then you're not in bad shape. I'd reccomment investing $6 in a new radiator cap and another $7 in a new thermostat and installing them. Installing the thermostat is pretty easy, and will give you the chance to refill your coolant. If you want to just text your thermostat,. remove it and put it in some boiling water and see if it opens, you can even test it to see at what temperature it is opening. There is no way i'm aware of to test the radiator cap, find a friend with a 240sx and use theirs, or break down and spend the whopping $6.

7. If you've check all of that and found your problem, you're more than likely going to have to refill and bleed the coolant. To do so, follow these steps properly to ensure all air is out of the system. Air in the system will circulate around and cause the temperature to rise, even blow the headgasket.

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. when it's at operating temperature, open the radiator cap, and loosen the bleeder screw. This screw is located above the intake, it's a 10MM and has some japonese writing beside it. You'll see what im' talking about.4. Open the bleeder screw, and pour 50% coolant 50% water 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 themto make sure you get all of the air out of them.5. After keep doing this until you get only coolant out of the bleeded screw, no air at all. 6. Close the bleeder screw, top off and close the radiator cap, and you're done!

Hope this helped, i'm gonna see about getting this made into a faq or something, i've never written a 30 minute response before.

Any questions or problems let me know.[email protected]

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s13ofdoom
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hey this may help!! the fan infront of my radiator is dead no worky work!! when i drive around get some air in there it cools down could my problme just be this fan? for ex. when i sit at a stop sign i can see if movin up after a while then i gun it and when the air hits it my needle goes down! well ur what do u think! k thanks

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quiksilvia
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its the fan

CanadianCoch
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lolthat woulda helped a long time ago imo, lol

DING DING DING, we have a winner

Dr.


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