Yz400f shooting coolant out

3 replies to this topic
  • JMacklin

Posted April 14, 2014 - 05:43 PM


It's a 99 yz400f just replaced the water pump, shaft and seal was bad. Not to bad for a 15 year old pump, but now it's coming out The overflow past the cap. Changed the cap out, and still pushing all the coolant out down past the cooling fins. More than 16 oz. thinking it's the head gasket. I was on a poker run out 35 or so miles when I noticed it getting hot from the water pump leaking. Filled it up with my drinking water to get back but don't know I'd the damage was done or not. What do you think? Thanks for your time.

  • motofella

Posted April 15, 2014 - 02:21 AM


Did you bleed the coolant system properly? There might be a air pocket somewhere causing it to overheat?

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  • JMacklin

Posted April 15, 2014 - 03:17 AM


Probably not, but it does it as soon as I start it. I will go back and bleed it out again.

Edited by JMacklin, April 15, 2014 - 03:20 AM.

  • Jdrost72

Posted April 15, 2014 - 03:32 AM


Also head gasket

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