Coolant leak.

My car is leaking coolant from underneath the engine.
Experienced mechanics share their insights in answering this question :
A cooling system pressure test using dedicated equipment will be able to pinpoint the location of your coolant leak. Running a vehicle low on coolant can cause it to overheat, resulting in extensive engine damage. My best advise is to have your vehicle inspected by a trained professional, such as one from YourMechanic, as soon as possible.

How to Identify and Fix Common car Problems ?

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The water pump in your Jaguar is vital to helping coolant flow through your engine. When the water pump seal wears out over time it can lead to a coolant leak. This issue needs to be taken care of immediately because if left unattended you can encounter numerous other issues such as engine overheating and damages.
Corrosion within the radiator is one of the leading reasons that coolant leaks. As the tubes get older and weaker, you may get sediment or debris inside that causes a leak. The sealing gasket between the tank and the radiator can also wear out, and that could lead to a leak.
Gaskets and Seals

One common place of a coolant leak is the radiator pan gasket. The drain plug can also cause leaking, and if the cap that seals the radiator can no longer contain the pressurized coolant, it will leak or spray out from underneath.

Is It Safe to Drive with a Coolant Leak? While driving with a coolant leak doesn`t pose an immediate threat to your well-being, we highly recommend that you avoid doing so. Driving a car that is leaking coolant can cause serious damage to your engine. Your engine can overheat, costing you big time.
It may be a broken hose and/or a hole in the radiator. Solution: Check your hoses to see if any coolant is coming out. Replace the hose(s) if you notice coolant coming out of them. If you notice coolant leaking out of your thermostat that can be an easy fix.
A coolant/antifreeze leak can occur for a variety of reasons, including a blown radiator hose, a bad hose clamp, warped head gasket, or the most common reason, a foreign object kicked up by the truck in front of you penetrating the radiator itself.
after your car sits for long periods, it`s typically evidence of a damaged cooling system. While you might not notice a small leak when your car is parked for short periods of time, letting your car sit for a while gives the liquid time to collect into a noticeable pool.
Technically speaking yes you can use plain water in your cooling system but it isn`t recommended as a long term solution and certainly not in extreme weather conditions.
If you suspect an internal coolant leak, allow the radiator to cool, take off the cap, and look for signs of oil or frothy bubbles in the radiator or header tank. With the engine running, smell the coolant itself – if there is a whiff of exhaust gas , the cylinder-head gasket may be leaking.
Depending on the severity of the leak, it can last from 10 to 50 thousand miles. In a severe case, the solution may not work at all. If your car is leaking, you should look for a better radiator repair solution.
Providing that the engine is running well, with no leakages or damage, you can expect a coolant loss of 0.25% every four to six months. This means a loss of two to three ounces a year is completely normal.
If your leak is because of something more serious, such as a blown head gasket, your fix is not so simple. While replacing a bad head gasket is the best way to go in the longterm, such a replacement is very labor intensive and expensive, and you may be able to use a sealant for less serious cracks or breaks.
Antifreeze leaks can be caused by a variety of things but the two most common factors are age and dirty coolant. Dirt or oil in your coolant can accelerate wear in your system, leading to leaks in your water pumps, at gaskets, or at o-rings. Flushing your cooling system is the best way to stop this type of leak.
Coolant Leak Below the Exhaust Manifold

You may notice radiator coolant (antifreeze) leaking under your car. Where the leak is coming from can tell you a lot. If it is coming from directly below the exhaust manifold, this is a clear indicator that the head gasket is failing and needs to be replaced.

A slow coolant leak may not leave you stranded, but without addressing the leak you still run the risk of overheating your engine. Coolant is essential when it comes to keeping your engine cool. Any time your coolant system is compromised, it is crucial to get it checked out.
If you do see a coolant leak under your car, it could be from a blown head gasket, but it could also be from a number of other problems. Typically, if the head gaskets look normal, the problem is in the radiator. Remember, the coolant cycles through the radiator to lose heat it collected in the engine.
What happens if you mix water with a 50/50 antifreeze? You`ll get a more diluted antifreeze which will allow freezing at a higher temperature than the original mix.
With the engine off, open your hood and locate the water pump pulley. With gloves on, grab it and wiggle it back and forth. There should be no movement, if there is, this along with the noise is a good indication you may have a water pump problem.
If the coolant level is dropping and there is no external leak evident, then the coolant is probably leaking internally, into the engine. If the car has recently overheated then this could have caused the head gasket to fail.
Fresh antifreeze is a clear brightly coloured liquid, usually blue, red, green, violet, yellow or orange but this will vary depending on the manufacturer`s formulation. Over time, your coolant will become dirty losing its colour and becoming darker, often an oxidized shade of brown.
Start your car`s engine and allow it to idle. Look through the radiator filler neck to see if the coolant flows. At this time, it should not be flowing as your car has not reached the operating temperature to cause the thermostat to open. If you find the coolant is flowing, it means the thermostat valve is open.
Typically you won`t need to replace a radiator cap very often, but it`s recommended you do so every 5 years to prevent issues from popping up.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

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.

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My car has a coolant leak
ANSWER : Hello. The most common cause of a random coolant loss on this vehicle is a leaking intake manifold gasket. It commonly starts leaking coolant into the engine, which will be burnt off or will leak externally. I typically do a pressure test and a dye test on the system first to see if I can locate an external leak. If nothing is found, then I do a block test to make sure that there is not a head gasket issue. If nothing shows up there, then I replace the intake gaskets. If you need to have this done, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose the coolant leak and replace the intake gaskets if necessary.

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My car is leaking coolant and telling me to stop the car and check coolant.
ANSWER : Going by your description and the age of the car, I’m going to guess you have a problem with your water pump. The water pump has a rotating seal that often doesn’t leak unless the engine is running. If your water pump is leaking you might be able to see a drip from the bottom of the engine front cover. Before jumping to any conclusions though, you should have a professional pressure test the system to be sure. If you contact Your Mechanic. they can send a technician to your home or office to check out your leak and tell you what it will take to solve it.

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Coolant leaking 2009 Volvo Diesel D5 engine
ANSWER : Hello – coolant leaks have many sources, sometimes very subtle to locate. Since coolant evaporates on a hot engine, it is often hard to trace to it’s source. It is still possible you have a blown head gasket (early stages), or simply a leaking pipe/hose connection, freeze plug, or other housing that attaches to the engine coolant system. I would recommend a cooling system inspection by a mobile, professional mechanic trained in tracking down these problems, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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Car leaks coolant when left overnight
ANSWER : Hi there. In some instances, after a radiator is replaced, a coolant line can be left loose by accident or can come loose as the hose clamp gets hot. If the car is parked on a slight uphill slope, the radiator coolant might be leaking from one of the top cooling lines or from the radiator overflow reservoir hose.

The best way to know exactly where your vehicle is leaking coolant from is to have a local mechanic, such as one from YourMechanic, come to your location to complete an inspection to determine the source of the leak.

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My car has a coolant leak – 2001 Lincoln Town Car
ANSWER : The heater AC (air conditioning) case has a drain to let out condensation from the case. The heater core is positioned in the case that allows it get out through the case drain on the outside of the engine firewall between the center toward the passenger side of the car in the case of a leak. Bypassing the heater core has stopped the leak but the heater and defroster is not inoperative along with the automatic temperature control of the air conditioner. I recommend having the heater core inspected and replaced to fix the system.

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Oil leaks into coolant & coolant leaks into oil
ANSWER : If the engine is not overheating or running badly, then yes an oil cooler is most likely the issue as it it will allow oil and coolant to mix. Other possibilities are a bad cylinder head gasket or cracked block, but this will generally affect how the engine runs as the combustion chambers are also affected. To have this checked, you may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the tools and expertise to diagnose the oil/coolant leak mixing and perform any needed repairs.

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Leaking coolant and coolant jug has to be filled every other day
ANSWER : There are more than five different coolant hoses on your Mitsubishi Montero that may be causing the coolant leak. Without being there to physically inspect the vehicle, it’s hard to diagnose precisely which one is causing the leak. The fact that you’re refilling the reservoir every other day is alarming and should inspire you to have a local mechanic diagnose the source of the coolant leak before it creates a serious overheating situation.

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