Tech Tip: Heater Core Leak Repair – UnderhoodService

Tech Tip: Heater Core Leak Repair

A classic sign of a heater core problem is when the inside of the vehicle's windshield persistently keeps misting. Warm coolant is leaking out of the core into the vents and then condensing against the cooler surface of the windshield.

A classic sign of a heater core problem is when the inside of the vehicle’s windshield persistently keeps misting. Warm coolant is leaking out of the core into the vents and then condensing against the cooler surface of the windshield. The automatic response is to turn up the blowers to try and clear the mist, but this only compounds the problem. 
The solution is usually to remove and either repair or replace the heater core. However, this is a particularly time-consuming task, which on older vehicles is often not cost-effective. An alternative solution is to treat the cooling system with a total coolant leak repair additive. These are designed to flow throughout the cooling system, including through the heater core, to make a quick and low-cost repair. Look for a ceramic-based coolant friendly product, ideally one that conforms to ASTM D-3147.

You May Also Like

HVAC Sensors: More Than Just Temperature

When a driver sets a temperature in the control head of an HVAC system, what does it mean to the vehicle? Seventy-two degrees could mean many different settings depending on the outside temperature, humidity and even the position of the sun.

When a driver sets a temperature in the control head of an HVAC system, what does it mean to the vehicle? Seventy-two degrees could mean many different settings depending on the outside temperature, humidity and even the position of the sun.

When a passenger decides that 70 degrees is a better temperature for their zone, things get even more complicated. Automatic Temperature Control (ATC) systems require a complex array of internal and external sensors that include ambient air temperature sensors, interior temperature sensors, outlet duct and evaporator temperature sensors, pressure sensors, humidity sensors, blend door position sensors and sunload sensors.

Nearly 5,000 To Participate In Auto Value, Bumper To Bumper ‘Festive Walk’ To AAPEX 2018

On Thursday, Nov. 1, nearly 5,000 Auto Value and Bumper to Bumper automotive professionals wearing matching yellow shirts will begin their “festive walk” from the Mirage hotel to AAPEX 2018 at the Sands Expo, temporarily shutting down the busy Las Vegas Boulevard along the way.

Drive Belt Checklist: What Are You Missing?

You might have only one chance to sell a customer a new serpentine belt. With belts lasting roughly 90,000 miles, proper inspection at the time of failure is critical not only for selling the belt, but also for ensuring add-on sales and better customer satisfaction.

VIDEO: Using Airflow To Sell Cabin Air Filters

Andrew Markel introduces an inexpensive tool that can assist in selling cabin air filter replacements. Sponsored by Auto Value and Bumper to Bumper.

airflow-selling-cabin-air-filter-video-featured
Air Conditioning Odor Causes

Air conditioning odors typically result from the uncontrolled growth of bacteria and other microorganisms in the evaporator. Research by independent laboratories has found fungi such as Aspergillus, Cladesporium, Penicillium and others growing on cooling coils and other A/C system areas.

ac air conditioning smells featured

Other Posts

Climate Control Modules

HVAC control modules may fail when the contacts and switches become inoperable. Sponsored by The Group Training Academy.

Dorman Launches 300+ New Products In November

Among the new products is an OE FIX climate control module designed to fit 1.7M Chevrolet Express & GMC Savana vehicles.

Curing Springtime Air Conditioning Smells

Air conditioning scents can come from a host of things.

VIDEO: R1234yf A/C Update

Andrew Markel answers questions about the new refrigerant, R1234yf. Sponsored by MAHLE.