MOTOR CLINIC SERIES: COOLING SYSTEM SERVICE

Cooling system operation and procedures for identifying system failure are described. Cooling system breakdowns are generally easy to diagnose. Once the steam has cleared, a cooling system pressure tester reveals the broken hose or leaking radiator that has allowed coolant to escape and cause overheating. When a simple visual inspection and cooling system pressure test will not pinpoint the problem, advanced knowledge of cooling system operation is required. Due to the heat transfer concept, a radiator pressure cap should never be removed until the mechanic squeezes the top hose to check for pressure and heat. Releasing the cap will not cool an overheated engine, and may burn the mechanic. The addition of ethylene glycol to water raises the coolant boiling point. The combination of a pressurized system and antifreeze makes it possible to sustain extremely high engine temperatures without boiling. A solution containing more than 68% ethylene glycol will actually result in less freezing protection than a weaker solution. Pure ethylene glycol has a boiling point far above the safe operating temperature of an engine, and water is required to activate rust inhibitors in a radiator. Cooling system diagnostic and tuneup procedures are detailed.

• Corporate Authors:

  Hearst Books

  Motor Books Department, 224 West 57th Street
  New York, NY  United States  10019
• Authors:
  • Cerullo, B
• Publication Date: 1980-5

Media Info

• Pagination: 6 p.
• Serial:
  • Motor
  • Volume: 153
  • Issue Number: 5

Subject/Index Terms

• TRT Terms: Automobiles; Cooling systems; Diagnostic tests; Engine tuning; Mechanics (Persons); Motor vehicles; Repairing
• Uncontrolled Terms: Overheating
• Old TRIS Terms: Tune-ups
• Subject Areas: Safety and Human Factors;

Filing Info

• Accession Number: 00382552
• Record Type: Publication
• Source Agency: National Highway Traffic Safety Administration
• Report/Paper Numbers: HS-029 028
• Files: HSL, USDOT
• Created Date: Apr 30 1984 12:00AM