overheating

Hi there,

Did they do a core clean with the flush? i would have it done if not, also replace the thermostat and check that the pressure cap is ok, check cooling fans are drawing air, start here,

This guide should help

https://www.2carpros.com/articles/engine-overheating-or-running-hot

Mark (mhpautos)

Hello


First ensure coolant level is full and that radiator fan(s) come on properly. Also feel radiator hoses to ensure coolant is being pushed through system properly. Flush may have dislogded some dirt/grime that was sitting harmlessly and now got it lodged into an area restricting the flow.

my blazer started over heating this morning when i got home this afternoon i changed out the thermostat and added a little water to the radiator before putting the cap back on i started the blazer to make sure that the water was flowing after a few mins i could tell that the new theromastat was opening like it should but my car is still over heating

do you have any leaks any where.

my 98 did that i had a leak in the water pump but it was so small you couldnt see any drips i replaced the water pump and it stopped over heating

About a month ago, my Blazer overheated. I added a jug and about a 1/4 of 50/50 antifreeze. I have not seen any radiator leaks or seen any water on the ground. One time since a light on the dash came on telling me to look at my gages. The car was overheating. Not having far to go I kept going and saw the temp gage go back to normal (?). I checked the water level and added about a quart of 50/50. I have a 5 mile commute. Yesterday/today it began to over heat. I smell the heat when I get off the car (the heater core is disconnected). I checked the water level and it is fine. I do not know where the water went. I do not have white smoke. Any thoughts.

Hi gcaleron, Welcome to 2carpros and TY for the donation

If you haven't check the thermostat do so or just replace it, also might want to check the radiator if its clogged-up feel for cold spots if any possibly its clogged also test the water pump

One way to test for a bad water pump is to squeeze the upper radiator hose when the engine is hot and idling. Careful, because the hose will be HOT! If you do not feel much coolant circulating through the hose when you rev the engine, the pump may be bad. The other cause might be a bad thermostat that is not opening properly (remove and inspect the thermostat), or a clogged radiator.

If it continues to overheat try bleeding the system could be airlock-continues to overheat get it block and pressure tested

My 99 Blazer keeps overheating. I add a gallon of antifreeze once a month which makes me think i have a small leak in the radatior but I have replaced two thermostats and a waterpump and flushed the radaitor. When my car overheats. I have no heat in my car just ice cold air blowing out. Do you think it could be my thermostat sticking and causing pressure, which fills my overflow tank up causing it to drain out all my fluid thus causing my car to overheat or do you think it could be something else.

Maybe its a major air bubble in your cooling system, turn the heater on and the rad cap off and see if anymore air comes out.

1999 Chevy Blazer 6 cyl Two Wheel Drive Automatic

I have replaced the radiatior,the water pump,thermastat and the cap. my brother said he had put some stop leak in it about a mo. ago what else can be wrong ?

Test the thermostat if it continues get it block and pressure tested-could also be airlock try bleeding it and see what happens.

Engine Cooling problem
1999 Chevy Blazer 6 cyl Four Wheel Drive

can't the fan off to change out waterpump

Removal of this requires a special wrench. You must remove the nut on the fan clutch with the special wrench before you can remove the fan. Check your local auto part stores for the tool.

Engine Cooling problem
1999 Chevy Blazer 6 cyl Front Wheel Drive Automatic

already changed hoses. they not leaking. used stop leak product. worked a couple of weeks. leaking again.

Hi there,

Stop leaks are a waste of time and money, get a cooling system pressure test done as this will locate the external coolant leak, do this first.

mark (mhpautos)

ok my blazer has a small slow leak in the radiator, but today i realized the overflow was bone dry when fluid was added just a few weeks ago and it was full. i check the fluid in the radiator before i did anything and it was full by the overflow was bone dry. filled the overflow completely and let it sit for about 10 mins then began to drive and it still was steadily increasing in tempature, plus the oil pressure gauge was bouncing up and down. when i got home i popped the hood and saw that 1/3 of the fluid i put in was used up already but there were no signs of a major leak just the small one next to the engine oil cooler line at top of radiator. im going to try stop leak but could there be something else wrong that is causing the overheat and oil pressuer gauge fluctuate?

Don't use stop leak it will just ruin the radiator best to relace the hose and check your thermostat to see if its functioning. Also have someone check your fuel system to see if its running lean this cause the car to run hotter than normal,

I recently replaced the water pump on my blazer. At the same time I flushed the coolant system which I don't believe had ever been done. It still had the old orange dex cool in it. I used a cleaner and made sure I flushed until all water was clear. I refilled with coolant and water mix but the truck would not take any where near the specified amount (11.9 quarts). I ran the truck with the radiator cap off and slowly added more coolant to the system trying to release any air. The truck went to overheat so I shut it down. Coolant water mix starting coming out of a line down by the radiator drain plug? I am at a loss. Do you think I have air in the system or something else possibly blocking?

Is the radiator leaking ? if not check the thermostat, make sure the radiator is not clogged-up-is the coolant circulating-if it continues to overheat get it block and pressure tested.

I have a 1996 Chevy Blazer ZR-2 that I recently replaced the thermostat in and my truck was able to run without overheating for about an hr and a half so I could drive back to college, however once I parked it and went to leave again several hours later it started to overheat again very quickly and does every time. I checked underneath it after leaving it and don't see any puddles from any leaks.. .any suggestions??

After you replaced the thermostat, there is a possibility you had an air bubble in the system. After you fill the radiator and run the engine for a bit, the air will circulate out, but the coolant level will be low, which would cause an overheating problem.

Is there any white smoke coming out of the exhaust? How is the coolant level when it overheats?

In degrees F, how hot is it getting? Does the radiator fan turn on?

Just did a complete oil change and tune up, just bought it. It was running sitting in a parking lot, for 15 min, and the oil pressure all of a sudden oil pressure went down to about 20 psi, and the temp went ALL THE WAY UP!!! But the oil was full, and it is not leaking oil from anywhere that I can see. No oil on the ground, and no oil in the water. Water is full. Turned it off for 45 min, restarted it to try to get home, and temp was below 200. Within 3 blocks, it was all the way back up again. And I was driving with the heat blasting!!! What is wrong? please help, single mother need a car :(

It sounds like you may need a thermostat. I would start with that. Get a thermostat and gasket and replace it and see what it does and we will take it from there. If you need help with how to do this please just ask.

It is getting extremely hot and smoking, the radiator fan is turning on

If the fan is belt driven, it will run with engine running. Just for testing, remove the thermostat, hook everything back up. With radiator cap removed, can you see coolant? If so, start the engine, can you see coolant flow? The flow should instant, without the thermostat. If no flow, check the water pump.

Maybe the radiator needs to be flushed? Does it run any cooler without the thermostat?

Oil pressure is good?

When I out the air conditioner on the vehicle overheats

Do you mean turn off the Air Conditioner?
Do you have an electric radiator cooling fan?

yes to both questions

Check to see if the cooling fan turns 'on' when the A/C is on -- and check if it turns off when the A/C is turned off....I am assumeing it does....

Your engine cools itself by absorbing heat into the engine coolant and dissapating it to the outside. It does this by pumping coolant through the radiator and the heat is blown off by the cooling fan (as it blows air over the fins of the radiator).

The cooling fan is a VERY important item when it comes to cooling your engine. It is turned on two different ways -- #1. When the A/C control is turned on the fan should automaticaly turn on - thus cooling the coolant that is being pumped through the radiator which cools the engine..
#2. The cooling fan is also controled by the coolant temperature sensor (or sensors). When the coolant reaches a certain temperature, the coolant temperature sensor - switches the cooling fan relay - which turns on the cooling fan..Number 2 is probably where your problem is. Check the cooling fan relay. If it is good, then replace the coolant temperature sensor (CTS). Be sure to replace the sensor that controls the cooling fan -- there is another sensor that sends a signal to the temperature gauge. This sensor has nothing to do with the cooling fan control circuit...

My 1998 S-10 blazer 4wd keeps over heating. I have replaced the thermostat, had the system flushed, (which they said there was no blockage cuz it was flowing good) replaced the clutch and fan blades, cleaned the condenser and radiator to ensure proper air flow, also replaced temp sensor sending unit. The water pump is circulating. And thermostat is opening and closing but I keep overheating to the point steam is coming out the overflow tube. I'm not losing fluid and it's not mixing into the oil or tranny. What am I missing?

So is it overheating as far as the gauge reads?Have you tested your radaitor cap?If its not holding the correct pressure it will boil over the cap and that can cause it to overheat from the coolant loss.

I have a 1996 Blazer it just started to overheat. On the temp guage when it reaches 210 it doesn't want to go over 40-45 mph. I have changed the egr value, thermostat, and checked the fluid in the radiator. Any help will be greatly appreciated.

[quote:a6fa3e6a19="penfan"]Engine Cooling problem
1996 Chevy Blazer 6 cyl Four Wheel Drive Automatic 68,000 miles
----------------------------------------------------------------
I have a 1996 Blazer it just started to overheat. On the temp guage when it reaches 210 it doesn't want to go over 40-45 mph. I have changed the egr value, thermostat, and checked the fluid in the radiator. Any help will be greatly appreciated.[/quote:a6fa3e6a19]

Did you check the fan(s)? You have a clutch fan that is run by the belt. Try moving the fan from side to side if there is any play then the fan clutch needs to be replaced. If all it tight spin the fan, Then warm up the vehicle, spin fan again, did it spin the same? if so replace fan clutch.

Now some also have an eletric fan. If it does then start vehicle and turn A/C. Does the fan come on?

Post responses here in forum....

There is no play in the fan. With the engine cold the fan is a little hard to spin. After the engine is warmed up the fan spins freely.

[quote:85eedd7a03="penfan"]There is no play in the fan. With the engine cold the fan is a little hard to spin. After the engine is warmed up the fan spins freely.[/quote:85eedd7a03]

OK, there is you problem.... The fan cold should spin but with some tightness.... the fan warm or hot should be tighter than cold. The way it works is it has a reastat that as it heats up it tightens to draw more air throught through the Radiator for better cooling.

Replace the Fan Clutch

My blazer first started running hot like this....needle would shoot up into the red then fall quickly, then it would do it again. So i had the thermostat replaced and radiator flushed b/c the car had sat up for about 2 mos. w/o driving and the water looked rusty in the radiator. After replacing thermostat, I drove it home from the shop and around town and it ran fine staying at about 180-195 degrees. The next morning when I get ready to drive it to work, it overheats again, but this time the needle on the gage doesn't move to hot then cold, it stays on hot. So I parked it and drove my other car to work. I haven't noticed any water but I can check that again. could it be something is stopped up and the water can't run through like it should? Please help!! Other than heating the car runs great.

Check coolant level , then oil does it look normal?
If coolant low refill and alow engine to run for sometime to remove any traped air.
Let me know what you find
Thanks for Donate

I checked the oil and it looks fine, no water in it. Coolant was fine. Could there be something stopped up and the water can't flow like it should? I flushed the radiator but do I need to do it again?