Overheating and boiling out the reservoir.
The issue started with a heater hose busted so i replace it and it was still overheating. Second thing i tried was the thermostat still overheated. Third thing was bypass heater core still overheating. Now i replaced the water pump and still overheating. From what i know i only have left to change is the radiator which i have just dont want to put it on and it no be it. The coolant looks clean and green so its no dirty. I squeeze the left bottom hose while its cooling from overheating and i hear it go back to the reservoir. I squeeze the top right going to the thermostat and same but hose is m
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Hey there. The next thing you need to do is confirm the thermostat is opening and test to see if the radiator is clogged or not. Begin by warming your car up. Don’t drive it, just let it idle or hold it on a high idle. Depending on the ambient temperature, this can take a half hour or more for the thermostat to open. You will know the thermostat is open by touching the upper radiator hose. The hose that comes off of the thermostat housing. When it begins to get hot, the thermostat is opening. The stat will cycle open and closed during the warm up process. A motor is not fully warm until the stat reaches a point of equilibrium. Meaning, it stays open at a constant amount. If your car begins to overheat and the upper radiator hose does not get hot, you will need to figure out what is going on with the thermostat. It could be installed wrong or even bad. I have had new stats be bad several times.
If the stat opens correctly and your car is fully warm, take it for a quick spin around the block. Come back to a stop in your driveway or other parking spot, turn the motor off, key off, open the hood and reach in and touch the radiator from top to bottom and side to side. You are feeling for cold spots. They will be obviously cold in comparison to the rest of the radiator. It is normal for the lower part of the radiator to be colder than the top. That only means the radiator is cooling as it should.
If after doing these two things your car still overheats, it is time to consider head gasket problems. You can use a block tester kit from your local auto parts store or you can book and appointment with us. Testing for head gasket problems can be cumbersome and only experience will allow you to make an accurate determination. I recommend a having an overheating inspection to have this accurately diagnosed and corrected.
How to Identify and Fix Common car Problems ?
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If the coolant doesn`t circulate correctly, the engine starts to overheat. You risk engine boil if your coolant level is too low, due to a leak or evaporation over time. Having your cooling system checked for blockages or potential leaks in the hoses will prevent an inconvenient roadside stop when the engine boils.
Why is my car`s coolant bubbling? Cooling systems in most cars are pressurised, and rely on a leak-free closed circuit of hoses to pump coolant/antifreeze around the engine. When air gets into this sealed system, air pockets can form and cause blockages, which can lead to bubbling and overheating.
The most common reasons a Volvo 240 is overheating are a coolant leak (water pump, radiator, hose etc.), the radiator fan, or a failed thermostat.
Coolant, or antifreeze, is essential to regulating the temperature of your vehicle. It`s also extremely toxic and designed to stay inside a closed system. If you`re seeing an overflow, it could be due to a radiator cap, thermostat, water pump, or radiator malfunction.
Air Pockets
As the vehicle warms up, the air pockets expand and are forced into the coolant reservoir. Because the expanding air pockets collapse when the engine cools, coolant is pulled from the reservoir to replace the air. As a result, the bubbles appear. This is a common occurrence, but it may be prevented.
If the car coolant is boiling, that means your car thermostat did not open to let the coolant go through, you have to replace it with a new thermostat to let your car coolant go through to enter the engine block cooling down the hot engine.
If your coolant reservoir is boiling but your engine doesn`t overheat, then your coolant may not actually be too hot. Those bubbles you noticed are more likely air bubbles that found their way into the coolant reservoir—not from the piping hot coolant. In most cases, the issue is actually a leak in the radiator cap.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Overheating and boiling out the reservoir.
ANSWER : Hey there. The next thing you need to do is confirm the thermostat is opening and test to see if the radiator is clogged or not. Begin by warming your car up. Don’t drive it, just let it idle or hold it on a high idle. Depending on the ambient temperature, this can take a half hour or more for the thermostat to open. You will know the thermostat is open by touching the upper radiator hose. The hose that comes off of the thermostat housing. When it begins to get hot, the thermostat is opening. The stat will cycle open and closed during the warm up process. A motor is not fully warm until the stat reaches a point of equilibrium. Meaning, it stays open at a constant amount. If your car begins to overheat and the upper radiator hose does not get hot, you will need to figure out what is going on with the thermostat. It could be installed wrong or even bad. I have had new stats be bad several times.
If the stat opens correctly and your car is fully warm, take it for a quick spin around the block. Come back to a stop in your driveway or other parking spot, turn the motor off, key off, open the hood and reach in and touch the radiator from top to bottom and side to side. You are feeling for cold spots. They will be obviously cold in comparison to the rest of the radiator. It is normal for the lower part of the radiator to be colder than the top. That only means the radiator is cooling as it should.
If after doing these two things your car still overheats, it is time to consider head gasket problems. You can use a block tester kit from your local auto parts store or you can book and appointment with us. Testing for head gasket problems can be cumbersome and only experience will allow you to make an accurate determination. I recommend a having an overheating inspection to have this accurately diagnosed and corrected.
My 05 equinox is overheating. Refilled coolant reservoir this morning for the reservoir was empty, but I cant find any coolant. Now heater is blowing cold.
ANSWER : Hi there. If the engine is overheating to almost at the red line but not there, then the issue would be the thermostat and leaking out the blow by hose. If the needle is going into the red line, then the coolant could be leaking out of a freeze plug and burning off on the exhaust or leaking into the engine causing the oil to mix. Check the engine oil and see if it is milky. If the oil is milky, then there is coolant getting in the oil through the intake gaskets or the head gaskets. If you need further assistance with your engine overheating, then seek out a professional, such as one from Your Mechanic, to help you.
Got new water pump less than 9 months ago. Now boiling sound and overheating smell. Temp says its good
ANSWER : Hello. The overheating issue your vehicle is having is likely not caused by the water pump once again. Though an inspection of your water pump performance should be checked when trying to diagnose this issue. The temperature gauge not going up to hot when the water is boiling will be a malfunction of the coolant temperature sensor. Overheating is likely caused by a faulty thermostat, a clogged coolant system, coolant system leak, or a bad head gasket. I suggest to have a technician perform an inspection of the possibilities I just mentioned including the coolant temperature sensor and it’s related wiring to help pinpoint exactly why the vehicle is overheating.
You are able to find a technician and schedule an appointment for your vehicle overheating here
https://www.yourmechanic.com/services/car-is-overheating-inspection
Overheating coolant reservoir has a pinhole in it. Is this the cause of overheating?
ANSWER : Hey there. If the coolant reservoir is leaking, then it could leak out enough coolant to cause the engine to overheat. The reservoir is known to get stress heat cracks and leak coolant. You might see a small pinpoint leak, but as the engine runs hotter it will push out more and more coolant.
I would suggest having the cooling system checked for overheating then pressure tested for the leaks. If the coolant reservoir is leaking, then have it replaced. Run the engine to verify the cooling system fans come on and the system does not overheat. A certified professional from YourMechanic can come to your car’s location to diagnose the leaking coolant if you need this taken care of.
I have a 2001 BMW 325i. It overheated, engine shut down. When cooled down (24 hours), while water poured in the reservoir I could
ANSWER : I’m not clear on where you see your leak, but if it is in the radiator tank itself, that will mean you at least need a radiator. If the car ran hot until it shut off, there may have been other damage to the engine as well. Many of the 325’s had a problem with a seal where the head gasket meets the front cover and allows coolant to get into the crankcase. You would do well to have this car thoroughly checked out before you operate it again. You can have that done at your convenience by contacting Your Mechanic. They can send a technician to your home or office to check out your overheating problem and let you know what it is going to take to fix it.
Coolant boils, not sure if overheating.
ANSWER : Hello. It does sound like a thermostat issue. If the thermostat is not opening as it should then this will occur. It also sounds like the radiator cap may not be holding pressure. I would typically test the thermostat and the radiator cap to see if they are failing and replace what is needed. From your findings I would say it is a good idea to start with the thermostat. If you want to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose this and replace your thermostat if necessary.
Engine Overheating after 20-30 minutes. Why?
ANSWER : Hi there. One of the easiest ways to test a water pump is to carefully place your hand on the lower radiator hose while the motor is running. Two things should happen; first, as you suggested, the hose should feel "hard" and you should always feel motion through the hose. One other thing to check is your heater. If the heater is not working (supplying hot air), then you’ve got an obstruction inside the heater core; which can also create overheating problems. If you can’t resolve your issues soon, feel free to contact one of our professional mobile mechanics and have them complete a car is overheating inspection.
My Nissan jus started overheating when it gets hot the coolant start smoking out the reservoir tank
ANSWER : Hello. Thanks for writing in. A cracked head or blown head gasket are causes for your symptoms. The system can get air trapped in it and cause overheating quite easily, causing the head gasket to blow. Cracked heads can emerge in a number of ways. However you will want to inspect some of the other components in the system first, because replacing the head gaskets can be a lengthy process. The overflow tank is serving its purpose, and catching the excess coolant as the engine heats up. However the vacuum that is created which is supposed to draw that coolant back into the radiator is not working, clogged, or has air trapped in it. This may be caused by a leak, which is common around the water pump. The first step is to find a leak in the system. Pressure test the system, and visually inspect for the coolant to leak. If you cannot find one, then the coolant has found a way into the engine. This may be through the head gasket, and worst case scenario a cracked head.
