Forum | Marketplace | Knowledge Base | | H1 site | H2 site | H3 site
Click Here To Visit Plan B Supply
Click Here To Visit Plan B Supply
Click Here To Visit Mod Mafia
Click Here To Visit Mod Mafia
Click here for a listing of all HUMMER Network sponsors

Hummer Knowledge Base

The Hummer Knowledge Base

Testing for Cooling System Air Leaks

  • With the engine cold (off overnight)
  • Remove overflow tank cap to equalize pressure
  • Replace cap
  • Start engine, let idle for about 30 seconds
  • Turn engine off
  • Remove overflow tank cap and listen for escaping pressure

If any pressure builds up during this brief time, there is a leak between the combustion part of the engine and the cooling system. There are many possible causes, including cracked head, cracked block, and head gasket failure.

Dave B.

Back to main page

The Hummer Knowledge Base is a collection of informative posts from the Hummer Network forums and mailing lists, contributed material and links to outside web sites.
The Hummer Network is not responsible for the accuracy of the information contained herein or on outside web sites, nor for any situation arising from the use thereof.
2006-2011 by The Hummer Network. No material from the Hummer Knowledge Base may be reprinted or republished in any form without permission.