Coolant leak after water pump repair

The car was with the mechanic @ dealership for 6 days while they fixed the water pump. After a couple hours of driving the fixed car, the 'check coolant' warning appeared. I topped it up, but the coolant keeps disappearing after minutes of driving. What's the likelyhood that this is a new unrelated problem, or a mechanics error?
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
If there are no visible coolant leaks, and there is no evidence in the motor oil of coolant contamination (the oil would essentially look like a chocolate milkshake), then the only likely source of the problem is a leaking heater core. If you are smelling any sign of coolant in the car, that would also point to a leaking heater core. I would suggest having a professional from YourMechanic come to your location to take a look at your vehicle to determine what may be causing this loss of coolant.

How to Identify and Fix Common car Problems ?

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When a water pump gets replaced, it`s not unusual to have some coolant leaking and for the weep hole to see some seepage. If the leak is small, it could just be from the seal`s break-in period.
A Coolant leak at the front and center of your car

A leak in this area is a likely sign of a faulty water pump. Leaks tend to occur when the gaskets and seals that connect the water pump to the cooling system fail as they get older, causing coolant liquid to leak and puddle under the engine.

Coolant leaks

It is common with Mercedes for the fitting to come off of the back of the driver`s side cylinder head where the heater hose is connected. If you notice coolant leaking externally from below the exhaust manifold, a blown head gasket is the likely cause.

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.
Before installing a water pump it will be especially important to flush, drain and refill the cooling system with the OE (original equipment) specified coolant mix. On the contrary, the correct operation of the new water pump would be jeopardized.
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.
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.
How much coolant loss is normal? 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.
The best way to confirm the source of the leak is to wash the radiator and hoses with water, and then start the engine and look for new signs of coolant.
Look for signs of coolant leakage—a light-colored residue or stain—around the radiator cap, on hoses throughout the engine compartment (check the ends where they are clamped to other components) and on the radiator itself. If it looks like a hose is leaking near a clamp, try tightening the clamp with a screwdriver.
An improper seating, damaged seal, or misaligned gasket can mean the water pump is not operating efficiently or, worse, is under undue stress from misalignment. Improper installation will likely also cause immediate leakage from the mounting surface.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

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.

My water pump is leaking but I replaced timing belt and pump a year ago. Can I just replace the water pump this time?
ANSWER : Hello. You can just replace the water pump in this case. Although, the cost of just the timing belt is fairly negligible in comparison to the total labor of the job. My estimator says the water pump is a 6.5 hour job. Multiply that by whatever the shop rate is and you have the total labor without parts. You end up saving about $100 or less on parts if you only replace the pump.

The deciding factor will be the condition of the timing belt. If it has problems, you won’t be saving yourself any money by reusing it. In addition, there are seals and pulleys that may need to be replaced as well.

Assuming all the related parts were replaced the first time around, there isn’t a reason you can’t reuse them. I would say you should weigh the savings of reusing them against the actual condition of the parts. This is best determined after a complete disassembly. Keep in mind, time estimates will vary a bit depending on many factors. Either way, the labor is the largest cost.

If you would like to have the water pump replaced, a certified professional from YourMechanic can come to your car’s location to perform this service at your convenience.

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.

Can a jeep run and drive without a water pump??
ANSWER : Driving or running the engine without the water pump working to circulate the coolant through the motor will cause the motor to overheat and may damage the engine costing thousands of dollars versus using a tow truck to take the vehicle to the shop that will cost a lot less. I would not recommend running the engine more than a few minutes at a time or you will overheat it.

I used stop leak to fix a slow leak in my water pump,it worked but the car went into limp mode after it.
ANSWER : Stop leak in the cooling system is likely to cause more problems than it will solve. Modern cooling systems are much more finely drawn and have far smaller passages than older cars, and stop leak will jam things up. I can’t think how it would make your car go into limp home mode however, unless it was a coolant level fault.Of course a code read is in order and that should tell the story. Meanwhile, it’s clear that you need to take care of that water pump problem It may appear to be fixed, but the leak will be back. If you want some help with this, you can Contact Your Mechanic. They can send a technician to your home or office who can read the codes on your Jaguar and tell you what this limp home thing is all about.

I was told I need a new water pump. Coolant leak into my left headlight. Car never overheated.
ANSWER : Hi, thanks for writing in. Water pumps will wear out eventually. Replacing them is very important to the lifespan of your vehicle. Temperature gauges in vehicles are largely misunderstood. They will only give you accurate readings if they are submerged in coolant. They are not designed to read the temperature of air, but of fluid. So they are only accurate if your coolant levels are within specification. If the leak has been traced back to the water pump, then that is likely the cause. You can inspect a few other components if you want to rule them out. The radiator is also very close to the headlight. The hoses running to the radiator are also a source that may be leaking. Tracing the oil leak is going to depend on the symptoms. Is there a visible leak, you can attempt to trace it.

If you would like help with this replacing your water pump, consider having an expert automotive technician from YourMechanic come to your home or office to perform the replacement for you.

I have a leak in the coolant system that I have narrowed to I believe is the water inlet tube off of the lower radiator hose.
ANSWER : First off, I would say it would be best to pressure test the cooling system to verify where the coolant is coming from. With the complexity of repairs to the cooling system on this vehicle, it may be worth the time spent to pressure test the system before tackling the replacement. Now then, as far as replacing the o-ring seal on the water pump inlet tube, it should really only require the removal of the bypass hose, lower radiator hose, and the two (or three, depending on manufacturing changes) mounting bolts that hold the inlet tube to the block. I personally would go ahead and replace the tube while I was there, instead of just the o-ring. Granted, this doesn’t mention what it will take to get down to the inlet pipe, but this is all it should take once you have access to it. If this is something that you feel you could use a hand with, consult with a certified mechanic, like those available at YourMechanic.com.

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.