Major Problem

7 replies to this topic
  • Freestyle666

Posted July 22, 2004 - 07:08 AM


:thumbsup: Hello there every one while riding my bike at the local beach showing my mates how the beast wheelies i noticed it was becoming hard to pop the front end up so i pulled up and noticed a lot of steam coming from the large breather that comes from the top of the head any how i tried to start the bike again and there was not a lot of compression there there was still some compression there but not the right amount so off home i went. Does this mean a trip to the local dealer who is very expensive or is there a way off solving this problem. My bike is a YZF400 1999 has regular oil changes and had a full bottom end rebuild november last year due to a cracked crank case, Any help will be much appreciated

Cheers Lee

  • yz426onNOS

Posted July 22, 2004 - 07:16 AM


Sounds like a blown head gasket.

  • Freestyle666

Posted July 22, 2004 - 07:21 AM


:confused:The head gasket was replaced november last year not a mechanic my self but shouldnt it last longer than a year

  • yz426onNOS

Posted July 22, 2004 - 07:41 AM


It should. Is your collent low? Maybe it was installed wrong. No offense. Maybe there is a scratch on the surface or some old gasket matriel left. Did you torque the bolts right? Are you pressure washing the bike? Did you do anything that shouldent have been done to the bike? Maybe you got a bad gasket?

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  • Freestyle666

Posted July 22, 2004 - 07:46 AM


It was installed by an approved dealer the coolant level is fine but i do pressure was the bike off after every ride there seems to be nothing leaking from the gasket and there is no oil mixing with coolant :thumbsup:

  • Freestyle666

Posted July 22, 2004 - 12:06 PM


Any one else got any ideas :thumbsup:

  • sirthumpalot

Posted July 22, 2004 - 02:10 PM


Head gasget sounds like a good guess to me too. Fill it with coolant, remove the rad cap and start the motor if you can. Look for bubbles in the radiator. If you see bubbles then the head gasget would be my first guess. Many things can cause a blown head gasget, the most common is probably overheating.

  • Davidyz450

Posted July 22, 2004 - 06:10 PM


you can buy a very inexpensive block check kit at any parts store. It checks for co2 in your coolant. There is between 12 and 15 percent co2 in normal combustion and there should be none coming out the radiator.

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