losing alot of rad fluid.After every ride there is no fluid left in the radiators???

9 replies to this topic
  • yz400f_Torqer

Posted December 10, 2007 - 10:25 PM


I noticed the other day I was riding,I stoped and seen fluid coming from the overflow hose When it was idleing.And when I got home there was no fluid at all left in the radiator.And when I was riding my leg was getting pretty hot from the header,was it overheating?And it holds fluid when its just sitting,when the bike is off.But it just looses it when its running.what could be the problem?thanks.please help:confused:

  • grayracer513

Posted December 10, 2007 - 10:28 PM


My guess would be a head gasket.

  • yz400f_Torqer

Posted December 10, 2007 - 10:29 PM


really???I hope not.The oil seems to be fine it isn't milky or anything????

  • grayracer513

Posted December 10, 2007 - 10:34 PM


Head gaskets don't have to contaminate the engine oil. It could also be a broken impeller/shaft, or just clogged radiators.

  • grizz rider

Posted December 10, 2007 - 10:38 PM


Replace the radiator cap the spring fatigues over time releasing anti-freeze out the over flow hose.

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  • yz400f_Torqer

Posted December 10, 2007 - 10:42 PM


would any brand of bike have the same radiator cap?

  • yamirider247

Posted December 11, 2007 - 10:27 AM


after you fix the problem you might consider changing over to the expensive fluid, since you only change it once a season. engin ice works really well

  • BergArabia

Posted December 11, 2007 - 09:10 PM


My YZ used to use a bit of coolant.. Not a lot, say 100 mLs.
But lately it has not been using any at all. So I am wondering if the riding style makes a difference. I think it does.

I definitely do not let the bike idle at all anymore like I used to.. I ride around in circles rather than sit on it with the engine running..

  • crazyal426

Posted December 11, 2007 - 10:45 PM


Try the Pit Posse on ebay. They sell a great HD cap about $20. Engine Ice ROCKS!!!!! Good Luck Cody!!!

  • SUnruh

Posted December 12, 2007 - 11:35 AM


here are somethings you should look for.

1) see if the impeller seal is leaking and letting it go out via the weep hole on the UNDERSIDE of the water pump housing. dust around this hole will tell you yes or no.

2) a pinhole in the radiator will pump it out faster than you can imagine, yet you will never know it is losing coolant.

3 & 4 what others have said above.

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