Coolant loss no leak - 2000 GMC Yukon XL

If your Hyundai H1 2018 model is losing water from the radiator at an alarming rate, even with a new radiator that is not leaking, there are a few potential causes for this issue:

1. Coolant leak: While you mentioned that the radiator is not leaking, there could still be a coolant leak elsewhere in the cooling system. Check for any visible signs of coolant leakage, such as puddles under the vehicle or wet spots on hoses, connections, or the engine. Coolant leaks can occur at various points, including hoses, water pump, heater core, or even the engine block itself. If you cannot identify any external leaks, it is possible that the leak is internal, such as a blown head gasket or a cracked engine block.
2. Faulty radiator cap: The radiator cap plays a crucial role in maintaining the proper pressure and preventing coolant loss. A faulty radiator cap can cause coolant to escape from the system. Inspect the radiator cap for any signs of damage, such as a worn-out gasket or a cracked cap. If necessary, replace the radiator cap with a new one and see if it resolves the issue.
3. Internal engine issue: Internal engine problems, such as a blown head gasket or a cracked engine block, can cause coolant to mix with the combustion chamber or leak into the oil system. This can result in rapid coolant loss without any visible external leaks. Look for symptoms such as white exhaust smoke, coolant in the oil (appearing as a milky substance on the oil dipstick), or an overheating engine. If you suspect an internal engine issue, it is recommended to have the vehicle inspected by a qualified mechanic to diagnose and address the problem.
4. Improper coolant filling or air pockets: If the coolant was not properly filled or if there are air pockets in the cooling system, it can cause coolant loss. Air pockets can prevent the proper circulation of coolant and result in overheating and coolant loss. In such cases, bleeding the cooling system to remove air pockets and ensuring the coolant level is at the correct level may resolve the issue.

Given the significance of the coolant loss and the potential complexity of the underlying problem, it is advisable to have your Hyundai H1 2018 model inspected and diagnosed by a qualified mechanic or Hyundai service center. They will have the expertise and necessary diagnostic equipment to identify the specific cause of the coolant loss and provide the appropriate repairs or solutions.

Has the radiator cap been replaced? try that first.

he causes of white exhaust smoke can vary; however, it is common to see white exhaust smoke when first starting a car, especially on cooler days. This is generally steam caused by condensation. As the engine warms up and the condensation dissipates the white exhaust smoke (steam) is no longer seen. If excessive white exhaust smoke is present well after the engine warms up, it is necessary to have the car inspected for possible internal coolant leaks. Indicators of an internal coolant leak include billowing white exhaust smoke accompanied by a sweet odor or a low coolant reservoir level. An internal coolant leak can also contaminate the engine oil giving it a frothy, milky appearance. Even small amounts of coolant entering the combustion chamber will produce white exhaust smoke.
One of the main causes of white exhaust smoke and coolant loss is a cracked or warped cylinder head, a cracked engine block, or head gasket failure caused by overheating. A cracked head may allow coolant to leak into one or more cylinders or into the combustion chamber of the engine. Dirty coolant, a poorly maintained cooling system, a low coolant level, or a non-functioning cooling fan can cause engine overheating. In addition, engine wear can eventually cause the gaskets to lose their capacity to seal properly allowing internal coolant loss. Intake manifold gasket and head gasket failures are two of the most common sources of internal coolant loss caused by engine wear.
Never remove the radiator cap or coolant reservoir cap while the engine is hot or running as it can cause serious injury; always allow the car to cool down completely first. Checking for a low coolant level in the reservoir is the first step in determining if coolant loss is causing the white exhaust smoke. If the coolant reservoir is at the proper level but excessive white exhaust smoke is present, a cooling system pressure check is required to determine where, if any, coolant leaks are located.

If it is leaking out that fast is should be pretty easy to see where it is leaking from. Find the leak, repair the leak and your problem should be solved.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

It is common to see white exhaust smoke when first starting a car, especially on cooler days. This is generally steam caused by condensation. As the engine warms up and the condensation dissipates the white exhaust smoke (steam) is no longer seen. If excessive white exhaust smoke is present well after the engine warms up, it is necessary to have the car inspected for possible internal coolant leaks. Indicators of an internal coolant leak include billowing white exhaust smoke accompanied by a sweet odor or a low coolant reservoir level. An internal coolant leak can also contaminate the engine oil giving it a frothy, milky appearance. Even small amounts of coolant entering the combustion chamber will produce white exhaust smoke. One of the main causes of white exhaust smoke and coolant loss is a cracked or warped cylinder head, a cracked engine block, or head gasket failure caused by overheating. A cracked head may allow coolant to leak into one or more cylinders or into the combustion chamber of the engine. Dirty coolant, a poorly maintained cooling system, a low coolant level, or a non-functioning cooling fan can cause engine overheating. In addition, engine wear can eventually cause the gaskets to lose their capacity to seal properly allowing internal coolant loss. Intake manifold gasket and head gasket failures are two of the most common sources of internal coolant loss caused by engine wear.
Never remove the radiator cap or coolant reservoir cap while the engine is hot or running as it can cause serious injury; always allow the car to cool down completely first. Checking for a low coolant level in the reservoir is the first step in determining if coolant loss is causing the white exhaust smoke. If the coolant reservoir is at the proper level but excessive white exhaust smoke is present, a cooling system pressure check is required to determine where, if any, coolant leaks are located. THESE LEAKS WILL CAUSE SEVERE ENGINE DAMAGE! Have the car inspected immediately.

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Internal coolant leaks can and will cause

Possible bad head gasket or cracked cylinder head.Check your oil and make sure there is no coolant mixed in. Have it checked at a reputable mechanic. Also check front passenger side carpet for heater core leak.

Bulletin No.: 03-06-02-005B
Date: November 18, 2004
TECHNICAL
Subject:
Engine Coolant Loss with No Visible Leaks (Reseal Injector Sleeve)

Some owners may comment on engine coolant loss with no visible leaks. Excessive white smoke or a coolant type odor coming from the exhaust pipe, along with low coolant levels, may indicate coolant in the combustion chamber.
Cause
Condition may be caused by engine coolant entering the cylinder due to a dirty or damaged seal between the fuel injector sleeve and the cylinder head.

If it's black smoke, you could have a faulty or dirty EGR valve and may not be closing 100%. Remove the EGR valve and clean it with spraying carb cleaner and reinstall after inspecting the valve can move without any binding. Goo luck and hope this helps.

The coolant system is a closed system. When the system is full the reservior acts as an expansion container. When the engine heats the coolant expands. The coolant expands into the reservior when the pressure cap releases. As the engine cools the coolant contracts and the radiator cap allows the coolant to flow back into the engine. If you are having coolant loss it should show as an external leak If there is no external leak it could be possible to have an internal leak. In theory this system should not lose anything but coolant loss on a small basis is expected. If your coolant loss is great and it is not seen externally I suggest that a pressure test involving engine components be done. I hope this can help Moe

this would more than likely be cause by a bad cylinder head gasket. I would bet 89% this is your problem.

Check the oil on the dip stick, if it is kind of brownish in color, it's a good indication the head gasket needs replacing, and no coolant leaks, but loosing coolant, is an indication also.