Can Mixing Red and Green Coolant Cause Major Engine Issues?

QuestionsCategory: Ask An ExpertCan Mixing Red and Green Coolant Cause Major Engine Issues?
Henry Samuel Smith asked 3 months ago
I recently encountered a situation where a coworker, despite my advice, mixed red and green coolant in her car. This resulted in clogging in the radiator, and the car's heater stopped working. The radiator hose even started collapsing due to the vacuum created by the water pump. I'm concerned about the potential damage to the engine and the heater core. How likely is it that there is gunk inside the engine as well? What steps should be taken to fix this issue?
1 Answers
Zack Norman Staff answered 3 months ago
Hi there, Henry! Mixing different types of coolants, like red and green, can lead to serious issues in the cooling system, which validates your concerns. These coolants have different chemical compositions and, when mixed, can create a gel-like substance that clogs the system. Here's what you need to know:
  1. Radiator and Heater Core Damage: If the radiator hose is collapsing, it's a sign that the coolant isn't flowing properly. The heater core and radiator might need replacement if they're clogged with the gel.
  2. Engine Concerns: There's a possibility that the gunk has reached the engine's cooling passages. If that's the case, it can lead to overheating and potentially more severe engine damage.
  3. Fixing the Issue: The immediate step is to flush the cooling system thoroughly. It might take several flushes to remove all the contaminants. Use distilled water for flushing to avoid any mineral deposits. After flushing, fill the system with the correct type of coolant.
  4. Professional Assessment: Given the potential severity of the issue, it might be wise to have a professional mechanic inspect the car. They can determine if there's any further damage to the engine or other components.
  5. Preventative Measures: In the future, it's crucial to use only the type of coolant recommended by the car manufacturer. Mixing different coolants or using the wrong type can lead to expensive repairs.
Remember, maintaining the cooling system is vital for the overall health of your car's engine, so I hope your coworker gets it fixed soon! Zack - Motor Verso Mechanics Team