Coolant Loss

5 replies to this topic
  • arel451

Posted May 25, 2006 - 02:26 PM


I was out riding this past weekend with some buddies, and my 04 450 was running great until we were doing some uphill runs on a deep sand hill. The motor was under a lot of strain, and I soon began to smell coolant. The bottom 1/4 of my right rad was wet and dripping coolant on my exhaust. I pulled the rad off and had it tested at 20 lbs pressure with no problem. I just noticed a round indent on the front of my cylinder just above the exhaust looks like something (like some kind of plug) was there, but now is not. Can anyone identify what was there and what I need to replace it with? I cannot find it in my manual. Thanks in advance.

  • cloute

Posted May 25, 2006 - 03:38 PM


Hey man read that we all have the same problem!!!

  • arel451

Posted May 25, 2006 - 03:50 PM


Thanks, I did try a search but I couldn't remember how to describe the problem. By the sounds of everyone else it sounds like that is my problem. I did think when I was checking it out all the oily mess smelt more like oil than coolant.

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  • cloute

Posted May 25, 2006 - 03:56 PM


Does this look like being your problem? If yes it's most likely gonna be the decompression plug missing.

Posted Image

  • arel451

Posted May 25, 2006 - 04:01 PM


Yup. Did you safety wire yours in?

  • cloute

Posted May 25, 2006 - 04:26 PM


No, that pic is from a website that sells aftermarket decompression plug. But it's not a bad idea, I'll do it for the new one I'll be putting in.

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