Over heating coolant not siphoning back into coolant over flow tank

About 2 weeks ago my car started to over heat as i was going on the highway. When i checked my coolant (after i let it cool made it home and let it cool completely) i noticed that the coolant overflow tank was completely empty but the radiator was over filled with coolant. Added more coolant to tank. Couple days later car wad over heating again opened hood and noticed the coolant was spilling out onto the ground because it was being spit outta the overflow port on the cap that goes to the coolant tank. Was told by one mechanic it was my thermostat. Had it replaced yesterday. Today care is sti
Experienced mechanics share their insights in answering this question :
Hey there:

It’s common for many mechanics to make the mistake of mis-diagnosing the cause of an overheating situation; especially when they assume it’s a thermostat issue. The problem could be caused by a blockage in the coolant tubes running from the radiator to the overflow tank and back to the radiator. However, it also may be due to air trapped in the coolant lines. I think a good idea would be to contact a different ASE certified mechanic, such as one from YourMechanic, and have them complete a coolant flush, which should remove any blockages in the coolant tubes and may solve your problem.

How to Identify and Fix Common car Problems ?

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If the coolant is not draining back into the radiator, you either have a defective radiator cap, or a significant leak causing a loss in pressure.
If your vehicle has a blown head gasket or a cracked engine block, combustion gases may escape out of the combustion chamber and into the cooling system. As the combustion gases fill the cooling system, they`ll push the coolant into the reservoir.
When there`s a leak in the cooling system, the pressure of the liquid drops and so does the boiling point of the coolant/antifreeze. Cooling systems are pressurised to raise the boiling point of the fluid, with the pressure cap and the overflow helping to raise the temperature at which the coolant/antifreeze boils.
For Q1 , if the overflow tank has the pressure cap on it the yes coolant will be drawn into the system. Otherwise the seal on the radiator cap will prevent flow in reverse.
Irregular Operating Temperatures

One of the most prevalent symptoms of thermostat failure is irregular operating temperatures. A stuck closed thermostat will cause engine temperatures to skyrocket, while a stuck open thermostat will cause an engine to run cool.

If the radiator cap is stuck, fluid cannot get released. This will cause pressure to build inside of the radiator, causing the hose to leak or break open. If you notice coolant near the radiator or the radiator cap, then you clearly have leaky coolant.

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Over heating coolant not siphoning back into coolant over flow tank
ANSWER : Hey there:

It’s common for many mechanics to make the mistake of mis-diagnosing the cause of an overheating situation; especially when they assume it’s a thermostat issue. The problem could be caused by a blockage in the coolant tubes running from the radiator to the overflow tank and back to the radiator. However, it also may be due to air trapped in the coolant lines. I think a good idea would be to contact a different ASE certified mechanic, such as one from YourMechanic, and have them complete a coolant flush, which should remove any blockages in the coolant tubes and may solve your problem.

No coolant in the reservoir. Seen low coolant message. I added 2 quarts of 50/50 coolant. Still getting the message. How much coolant doe it need?
ANSWER : Hi there. For the coolant light to go out, you would need to have the coolant between the low line and the full line for the light to go out. If the coolant is low and keeps on being low, then look for any signs of coolant leaks. You may have to use a coolant pressure tester to pressurize the reservoir to allow the leak to be found.

If you need further assistance with the coolant being low and the warning light being on, then seek out a professional, such as one from Your Mechanic, to help you.

A piece of cardboard/paper from the coolant jug was accidentally dropped into the coolant tank.
ANSWER : Unfortunately, this tiny piece of cardboard will not dissolve in coolant as it is designed to withstand the chemical makeup of the coolant. This can become lodged in areas inside the radiator that will prevent the proper flow of coolant through the passages. I would suggest having an expert from YourMechanic come to your home to properly remove the debris from the radiator at your own convenience.

My car is spitting coolant from the overflow tank
ANSWER : Hi and thanks for contacting YourMechanic. Check the coolant strength to see what the protection is. A good protection will read 164 degrees Fahrenheit. Check the radiator cap to see if the seal is torn or if the release valve inside the cap has failed or is sticking open. A radiator cap can cause the system to boil and spit out all of the coolant.

If you have good coolant and the radiator cap is new, then the thermostat could be sticking causing your coolant to heat up too much which in turn causes the system to boil. To check if the thermostat is working, start up the vehicle when it is cold and watch the coolant temperature gauge. When the thermostat opens, the gauge will drop a little.

If the gauge does not show this, then, when the upper radiator hose gets hot, right after the thermostat opens, the coolant flows through the hose and you would be able to feel this. Plus, the hose will begin to get cooler as the coolant travels through the hose. If the thermostat was replaced and you still have a boiling issue, then the head gasket has burned on the engine.

If you need assistance, then seek out a professional mechanic, such as one from YourMechanic, to help determine why the car is overheating and why the coolant is boiling out.

A/C and heat are not working properly. Car blows heat in summer and cool air in winter.
ANSWER : Common causes of no cabin heat include malfunctioning blend door(s) (part of the in-dash ventilation network), a faulty or stuck heater control valve, a plugged heater core, stuck open engine cooling thermostat, collapsed hoses, and low coolant level. The cost to resolve the problem depends on which of the foregoing faults is the cause. If you desire a diagnostic to determine exactly why there is no cabin heat, please request a non functioning cabin heater diagnostic and the responding mechanic will come right to your location and get this resolved for you promptly.

With regard to your air conditioning system, if merely re-charging the system restored normal operation but the a/c ceased to function after a month or so, that scenario typically suggests a leak. Some leaks are really cheap to repair, like if a couple o-rings need to be replaced in system piping but if the leak is at the compressor shaft seal, that repair is more costly. It is not expensive to find the leak and diagnose the system and once the leak is found the mechanic can let you know of the exact cost to repair the leak and re-charge the system. If you desire that service please request an a/c system diagnostic – suspected refrigerant leak and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you

Car won’t start.leaking coolant antifreeze out of drain hose.changed coolant tank cause had a crack in it.now car won’t start
ANSWER : Hi there. There are several reasons why you might be experiencing overheating issues with your car. However, without knowing the vehicle details, it’s hard to give you a good diagnosis. It could be the water pump, bad thermostat, an air bubble in the coolant lines, or a blown head gasket in the worst case.

The best thing I can recommend for you is to contact a local ASE certified mechanic to inspect the vehicle’s starting issue and determine what needs to be fixed.

1996 F150 4.9 5 speed. Frt. Fuel pump quit working. Put fuel in rear tank and it sucked the fuel to the frt tank.
ANSWER : The two tanks are designed to work together and so BOTH pumps must be functioning and, as well, the related fuel system supply code, the Code P0232 that has set has to be resolved. P0232 means that the fuel pump relay is stuck on, keeping power supplied to the fuel pump even after the ignition has been turned off although another possibility is the fuel pump secondary power circuit has a short to battery voltage. The factory service manual (FSM) specifies a very lengthy diagnostic (because you have separate tanks). If you do not have the FSM, your best bet is to request a fuel pump diagnostic – dual tanks and let a certified mechanic get to the bottom of this. With regard to the other code, P0704, that code will set if the clutch switch is defective, there is worn clutch pedal lever or clutch lever bushing, shorted or open wiring and/or connectors in the clutch switch circuit, a blown fuse or burnt fusible link and/or, rarely, a faulty PCM or programming error. If you request the pump diagnostic the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

I have a 1981 e-350 with dual fuel tanks the p.o. added a third tank and 3 electric fuel pumps along with sepparate gauges and swi
ANSWER : The switch you are referring to is vended with the required electrical and fuel schematic (I just looked in the box) that answers your installation question. If you want an advance view, here is a link as well. Yes, you need a return line and just refer to the aforementioned link. If you are retrofitting back to OEM, I strongly encourage you to buy the original Factory Service Manual (FSM). There are lots of details attending this system and obviously it is difficult to recount it all here. The FSM will make your life much easier and you can then make sure your installation is perfect. Alternatively, YourMechanic can dispatch a certified mechanic and perform the whole retrofit and check out if you desire. Just request and schedule a generic service such as fuel pump service and the mechanic will come to your location and estimate the parts and labor required. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.