Antifreeze leak

ANSWER : Hi…stop leak products should never be introduced into a car engine’s cooling system simply because such aftermarket products are not a factory authorized or factory sanctioned repair technique. Some factory service manuals are indeed emphatic on this issue. A stop leak product is, in essence, a foreign contaminant and thus has the potential to plug up cooling passageways, the radiator and so forth. The only recognized technique employed by professional mechanics when it comes to a leak in the cooling system is to repair the leak, period. At this point, by far the cheapest and most effective strategy for you will be to have a mechanic identify the leak(s) (via pressure testing, if need be, on a cold engine), repair the leak, and thoroughly flush the cooling system to hopefully remove all traces of the stop leak product. The cooling system has to then be refilled with new coolant, while purging all air, and tested. On a vehicle with over 200,000 miles, it is possible the leak occurred along with other cooling system faults such as a failing thermostat, water pump, and possibly partly clogged passageways, particularly in the radiator. All of that will have to be evaluated to ensure that no further overheating occurs. To get this resolved promptly and professionally, by all means please feel free to request a leak diagnostic and the responding certified mechanic will get you squared away. If you have additional concerns or questions, please do not hesitate to contact us.

ANSWER : I would introduce UV leak detection dye into the system, pressurize the system while cold, and leave the system under pressure overnight (the pressure will slowly bleed off somewhat but such will not affect the test). If there is any external leak of significance, it will show up under the UV light.

If no leak is present and yet you still have a leak once the engine runs and gets hot, that means that the leak is between two surfaces that are opening up under hot engine operation. But the same protocol applies. That is, at that point, inasmuch as the leak detection dye is still in the system, you should just let the engine cool completely and use your UV light source again to methodically check all of the obvious possible areas of the system that could leak.

I recommend having a certified mechanic, such as one from YourMechanic, perform an inspection to determine the source of the coolant leak and suggest any needed repairs.

ANSWER : It is possible that your turbo is cooled with engine coolant and has sprung a leak. This would cause coolant to leak into the exhaust system because the turbo is connected to the exhaust system. It is also possible that because there is a turbo issue, this is preventing the vehicle from starting. I would recommend having any trouble codes read with an OBD2 scanner and going from there with the diagnosis. Consider YourMechanic for a car is not starting inspection as this can be done at your home or office.

ANSWER : If you are losing coolant from your radiator, the radiator will need to be replaced in order to stop the leak. When your coolant level drops past a certain point, the air conditioning will no longer work because the engine is overheating. I would recommend having a qualified mechanic perform this service to prevent any possible problems during the repair as well as having a warranty to go along with the repair.

After the radiator is replaced, I would the recommend having a cooling system pressure test performed to ensure that there are no more leaks in your cooling system. Once it has been verified that the leak has been repaired, have the air bled from the cooling system because any air that is left in the cooling system will cause the vehicle to overheat.

ANSWER : Coolant leaks no matter how big or small should be addressed as soon as possible. As you noticed, the engine will run hot with a low coolant level. Even a minor leak can expand to a large or catastrophic leak with no warning. A minor repair now can turn into engine overheat and damage. The leak can be small enough now that it is burning away when contacting hot surfaces and not hitting the ground. If the radiator leaking is the cause of the coolant loss, then it should be replaced as soon as possible. The cooling system operates under pressure – usually 12-15 psi. A small leak can become a large leak because of the pressure. Have a certified technician address this as soon as possible. Do not use "coolant leak sealer" products as they are a temporary fix and can actually cause more damage by clogging small coolant passages and damage the water pump as well.

ANSWER : If the oil filter housing is integral to the oil cooler, or the housing had to be removed to service the cooler, a professional mechanic with knowledge of the limited service life of rubber seals would have absolutely (guaranteed) replaced the filter housing gasket that you are now belatedly finding leaks. However, if the leaking gasket is in an assembly that was not touched, or is not part of the cooler, they might be on reasonable grounds to have not fooled with it. These cooler configurations vary (from Mercedes Benz model to model) so, having the advice I just gave, you can just simply ask them what configuration you have and go from there. The bottom line is, if indeed, the gasket that is presently leaking was "right in front of them" while they did the warranty work, it should have been replaced simply as a matter of course. Indeed, the weak link on modern engines has become gaskets and seals. The engine will mechanically far outlast the gasket and seals but the problem is to replace all of them (once they all leak) you have to literally take the engine out of the car and take it apart just to put all new seals in. Please let us know how we can help further on this issue.

ANSWER : Stop leak products are generally an amateur, unprofessional solution to a TECHNICAL problem. Factory Service Manuals do NOT recommend or specify stop leak products BECAUSE such products are NOT considered to be an acceptable repair strategy, save for rare exceptions. The composition of your question clearly indicates that you understand that the OPTIMAL solution is to just fix the gasket(s) and you are simply seeking a stop gap (no pun intended) measure while you prepare for that repair. After having researched these products for decades and having tried a few, talked to manufacturers and so forth, I would suggest that you just let the vehicle leak until it was repaired assuming of course that oil is NOT leaking onto a hot manifold thus creating fire and health hazards. Of course, it is best to just simply prioritize the repair and one possibility insofar as the cost, as well as the diagnosis, is to get a second opinion from YourMechanic.

ANSWER : Hi Ricardo. We answered your question earlier. However, if you didn’t receive the reply, here is what we stated earlier. In most cases, an EVAP leak will create an OBD-II trouble code. The best way to detect an EVAP leak is by having a professional mobile mechanic complete a check engine light inspection, they will be able to download the code and determine the source of the leak. That’s the best advice we can offer you. Thanks.