Be careful: spots or puddles under the car
Content
Spots or puddles under the car should never be left unattended. It always means some sort of leak. Sometimes this is completely harmless or even a technical necessity. However, most leaks are the result of a defect with possible annoying or even serious consequences. Read this article for everything you need to know about puddles under your car.
Fluids in your car
Several fluids circulate in a car, each with specific characteristics and a well-defined task. Only a few of them are allowed to escape. Summing up all working fluids in the car, the following list can be distinguished:
| - fuel: gasoline or diesel - lubricants: engine oil, transmission oil, differential oil - brake fluid - coolant - condensate in the air conditioner – liquid refrigerant for air conditioning - battery acid |
Step 1: Diagnosing puddles under the car
The first step in identifying a defect is to determine which fluid you are dealing with. This is simplified by the specific characteristics of the working fluids:
 Diesel and gasoline have their own smell . Diesel is a slightly oily brownish substance. Gasoline has a pungent odor and causes a specific iridescent shimmer when swimming on water, such as in a puddle. |
Lubricants are brownish or black and very greasy. Therefore, oil leakage is very easy to detect. Try rubbing a little of it between your index and thumb to determine its lubricating properties, preferably using disposable gloves from a first aid kit. Be sure to replace them afterwards, as their absence may cause verification problems. In addition, disposable gloves are indispensable when providing first aid to an accident victim in order to avoid infection. |
Brake fluid is an oily substance with a pungent odor. . It is light brown in color, becoming greenish with age. It is easy to determine by the place of the leak: a stain next to one of the wheels is a clear sign of a leak in the brake system. |
Coolants have a sweet smell because the added antifreeze contains glycol. This watery substance has a slight lubricating effect. Coolants often have a green tint, some types have a bluish or reddish color, depending on the antifreeze added. |
Condensation in an air conditioner is pure water and nothing else. . This is the only liquid that is allowed to come out. It occurs as a result of the normal operation of the air conditioner and its reset is technically justified and does not cause concern. |
The liquid refrigerant in an air conditioner remains liquid as long as it is under pressure. . Leakage of the air conditioner leads to the leakage of refrigerant in the gaseous state. There is no liquid residue. Therefore, spots or puddles under the car can never be the result of a faulty air conditioner. |
Battery acid almost never leaks . Typically, battery holders last longer than the life of the battery, meaning that the battery has failed and must be replaced before any leakage occurs in the holder. Theoretically, however, battery leakage is possible. Being an acid, it can be identified by its characteristic, pungent and penetrating odour. Further signs are very obvious: the caustic acid will leave its mark on the battery holder on its way to the ground. In most cases, the battery tray is completely corroded. |
Step 2: Finding a Leak
Once you are sure what kind of fluid you are dealing with, you can start looking for a leak. There are three ways to do this:
| – search on a dirty engine – search on a clean engine – search with fluorescent contrast liquid |
If you already know how to handle your car and its typical weak points, you can start by checking out a dirty engine. An experienced eye will immediately notice the leakage of oil and other liquids. With a certain degree of pollution, this can become more difficult. The old machine may have lost fluids at several points. . With a dirty engine, you run the risk of fixing one leak and not noticing another.
Therefore, it makes sense to thoroughly clean the engine before looking for a leak. . It is strongly recommended to work manually and professionally: brake cleaner, dish brush, rags, compressed air are the best tools here. It is not recommended to use a high pressure washer to clean the engine. A strong jet of water can cause water to penetrate into the control unit and ignition electronics, resulting in a malfunction.
An innovative method of engine cleaning is dry ice blasting. . Instead of liquid, the engine is cleaned with frozen CO2. FROM OK. €60 (± £52) this method is quite expensive, although the result is fantastic: the engine looks like it just came from the factory . This procedure is optimal for finding leaks.
Please note that in 20 minutes this is the fastest way to clean the engine without leaving marks.
After cleaning, let the engine idle. Now you should have no problem finding the leak.
The safest method for finding the cause of an oil or coolant leak is to use of fluorescent contrast agent . This method is not only very smart but also very practical and also very cheap. To search with a contrast agent, you must:
| - contrast agent for oil (± 6,5 pounds sterling) or coolant (± 5 pounds sterling). – UV Lamp (±7 GBP). – darkness (night, underground parking or garage) . |
The contrast medium is simply poured into the oil filler hole or expansion tank of the cooling system. Then let the engine run for a few minutes. Now illuminate the engine compartment with a UV lamp so that the leaked contrast material glows. In this way, a leak is detected quickly and without a doubt.
TIP: If you are looking for leaks in the cooling system AND in the lubricant, do not use both contrast agents at the same time. Consistent operation simplifies the detection of leaks.
Step 3: Repairing Damage Properly
There is only one reliable way to fix a leak in a car: its proper repair. . Leaky hoses must be removed, replaced with new ones, and not just wrapped with tape. Leaky brake lines should also be removed and replaced.
A defective gasket between two components must be replaced by removal, cleaning and proper installation. It doesn't allow for any rework or quick fixes. We decided to emphasize this, because the market for wonderful solutions in this area is huge. Therefore, we state very clearly:
Stay away from "Radiator Stop Leak" or "Oil Stop Leak" . These agents are short-term solutions at best. They usually only do more damage. Radiator Stop Leak can lock up the thermostat or degrade radiator performance. Oil Stop Leak may serve cosmetic purposes but cannot replace a failed gasket.
Brakes and fuel lines do not allow any impromptu solutions at all. A leak can be a nuisance, but it's a sign that your car needs urgent maintenance. .
Step 4: Be smart when you see puddles under your car
Leaks mostly occur in older vehicles that have not been checked for a long time. There is only one option here: thoroughly check the car and make a list of any necessary repairs.
If the brake system is leaking, the brake fluid must be changed. . In this case, the expansion tank, brake discs, brake cylinders and linings should also be checked. Since the car is disassembled anyway, this is a great reason to replace these parts.
The same applies to the radiator: if the car is old and the radiator hoses are porous, you can hardly expect the radiator to be in good condition . Be wise and invest additional £50 by repairing the entire cooling system, restoring the condition of this unit, ensuring long-term safety.
