Skip the auto shop - Our mechanics make house calls

Q: Car has a coolant leak

asked by on

My car recently developed a small coolant leak. It was near the area of the water pump, so I suspected the gasket. I didn't have time to fix the car, so I added a can of Barr's liquid aluminum stop leak. That helped for a few days, but then my son was driving the car and it started overheating. Turns out that there was a crack in the larger coolant elbow, which was spraying coolant up onto the top side of the hood. We replaced the elbows with aluminum ones, replaced the water pump and gasket, refilled it with coolant, and then drove around block. But after all of that, the car is still overheating all the way to the redline, and then the warning light coming on. We then replaced the thermostat and it still overheats. At this point my suspects are: A. air in system B. radiator clogged. C. heater core plugged (aka: is the coolant flow to the heater core in series or parallel with the coolant flow to the block?). D. blown head gasket. Any suggestions?

A: If you did not bleed the cooling system aft...

If you did not bleed the cooling system after performing the repair, there is probably air in the system. Air can be bled by running the engine with radiator cap removed and a special funnel installed, or by using a vacuum fill tool. If you properly bleed the system and the problem continues, it’s likely that the engine was damaged from overheating and/or the Bar’s Leak has clogged the cooling system. I suggest you have a trained professional diagnose your vehicle firsthand to find culprit of your overheating issue.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: New battery, car still wont start even with jumper cables.

If the battery is new and fully charged, and you turn the key to the "start" position and you hear nothing that means that either the starter circuit supplying the starter motor (ignition switch, wiring, relay, fuse, etc.) has a...

Q: Replaced Clutch but still not working

Hey there, thanks for writing in about your 2004 Ford Focus. Pressure bleeding may be the only way to get all the air out of the system. The process puts pressure into the master cylinder with fluid, and pushes the...

Q: Noisy steering, is it a dangerous problem?

Noisy steering is usually indicative of defective fluid, unless you have a leak and are low on fluid. In your case, I would recommend having a top-rated mechanic from YourMechanic run a power steering pump pressure-test and check the power...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...