The inlet hose for your heating system is the hose that goes to the water pump area. The other hose is the outlet. These flush kits will actually work on either one though as it does go through the entire cooling system.
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What hose is connected to the thermostat housing?
The upper radiator hose is connected to the thermostat housing and to the radiator. From the bottom of the radiator, is the lower radiator hose that is directed to the water pump.
How do I know where my heater hose is?

Should both hoses on a heater core be hot?
When the vehicle is at operating temperature feel the two hoses, the should be the same temperature. If one hose is noticeably hotter then the other then the heater core may be partially plugged or restricted.
What are the two small hoses on a radiator?
Your engine has two radiator hoses: an inlet hose, which takes the hot engine coolant from the engine and transports it to the radiator, and an outlet hose, which transports the engine coolant from the radiator to the engine.
Why is coolant leaking from thermostat housing?
Symptoms of a Leaking or Failed Engine Coolant Thermostat Housing. If your vehicle overheats, a failed or bad thermostat could be the culprit. However, a thermostat housing that has sustained damage is more likely going to give way for a coolant leak. This comes from either a failed seal in the engine or warped housing …
What happens if you put heater core hoses backwards?
You would effectively back flush your heater core temporarily. The scale and any gunk would be logged loose and now circulating in your cooling system likely to clog the radiator and possibly the core too. It also isn’t designed to be as efficient with fluid going backwards through it.
Do you have to drain coolant to replace heater hose?
From personal experience I strongly recommend that you drain the coolant using the drain plug at the bottom of the radiator. You don’t want to mess coolant inside the car. While you’re at it you might as well change the seal on the sensor that fits into the lower radiator hose as it will eventually wear and leak.
What is the hose connected to the coolant reservoir?
This is a vent hose that allows air to take the place of coolant that is used by the engine from the coolant tank. The hose also will vent excess coolant if you over fill the tank or the engine over heats.
Which heater hose does the heater control valve go in?
The heater control valve is typically in line with the heater core’s inlet hose, which is often near the vehicle’s firewall, but the exact location of the valve will vary by vehicle. To determine the location of your car’s valve (if it has one), it’s a good idea to consult a repair manual or repair database.
Which heater hose does the control valve go on?
The heater control valve (sometimes called the hot water valve) is used to control the rate at which coolant flows through the heater core. The valve is located on the heater inlet hose.
How often should heater hoses be replaced?
Heater Hose Replacement Answer: Heater hoses can last from five to over ten years. However, it is very important to test periodically the condition of your heater hoses. Wait until your engine has a chance to cool and then feel your heater hoses. They should not feel too hard and brittle or too soft and mushy.
How can I tell if my heater core is clogged?
- Weak or no airflow.
- Cold air (not warm) coming through the vents when the heater is on.
- Coolant leakage visible inside the cabin or a damp smell.
How do I know if I have a bad heater core or thermostat?
Sweet Smells in the Car It could be the heater core. If the heater core is leaking, it will blow the odor of engine coolant through the vents. Coolant smells sweet, almost musty. Many people say it smells like candy, fruit, or maple syrup.
Should my upper radiator hose be hard when engine is warm?
Yes, a radiator hose should be hard when your car engine is getting hot, because a high hot water pressure is building up inside the engine block and the radiator, the radiator cap is spring loaded, it will release the pressure to let the boiling coolant return to the overflow reservoir.
What is the hose that runs from radiator to engine?
A coolant hose is a long radiator hose that sends coolant from your engine and your radiator to other parts of your car. It often sends coolant to the water pump and is responsible for keeping your engine from working too hard and overheating. Your coolant hose is one of the most important parts of your vehicle.
What does a coolant bypass hose do?
The bypass feature allows water to flow around the engine, without passing through the radiator, while the thermostat is shut. Without it, the water will not circulate correctly creating hot spots around the engine which could lead to damage.
Is heater hose the same as coolant hose?
Coolant hoses and heater hoses are essentially the same thing, but applied towards different purposes. Coolant fluid, like Freon, is much more effective at cooling an engine (and heating a car) than regular water, because water boils and freezes much faster than Freon.
How do I stop my thermostat housing from leaking?
If the leak is at the hose, tighten or replace the hose. If the leak is at the flange gasket, remove the housing, scrape to remove all residual gasket material, apply sealant and a new gasket. Torque to spec. While you have the housing off, good idea to remove and replace the thermostat.
How do you know if your thermostat housing is leaking?
- the temperature gauge starts to read really high and the engine overheats.
- the temperature is changing in an erratic manner.
- the coolant will leak around the thermostat housing or under the vehicle.
Is thermostat housing leak serious?
With a leaking thermostat housing, the distribution of coolant throughout your engine will be severely compromised. With no coolant flowing or a significantly reduced amount, your engine is vulnerable to excessive heat and will produce high readings on your temperature gauge.
How much does it cost to replace a coolant hose?
The Average Cost for a Radiator Hose Replacement Is $15 to $424 Depending on if You Go to the Mechanic or DIY. This price range is based on national averages for all vehicles and does not factor in taxes, fees, or your particular make and model.
Why is it important to drain the engine coolant when replacing a heater matrix?
Without flushing, corrosion particles build up and begin to clog the radiator and heater core. These clogs can cause your car to overheat. If they get worse, they can ruin your entire radiator or heater core. This repair is typically expensive.
Do you have to drain coolant before replacing?
Some technicians suggest simply draining the old fluid and replacing it, but a full flush assures that the lines are clear of pollutants for maximum efficacy. Once the used coolant is emptied out and responsibly disposed of, distilled water is put in followed by a bottle of coolant flush.
What is a coolant vent line?
A venting arrangement for a cooling circuit of an internal combustion engine, having a vent line which connects a radiator to a top section of an expansion tank located at a higher level with regard to the top of the radiator.