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Discussion Starter · #1 ·
Rode my cx into town the other day to grab some drinks at the grocery store and on the way there i thought i smelled some coolant but didn't think much of it. Got home and noticed my temp gauge was up higher than normal and when I pulled into the barn there was steam coming form the upper left of the engine. So the initial inspection lead me to believe it was the upper radiator hose. After removing the upper radiator hose and its coiled metal shield i decided to replace the old hose clamps and reinstall to make sure it wasn't just a leak at the clamp.



With the new clamps the bike is still leaking and its not at the upper radiator hose.



This leads me to believe that the leak is coming form either the thermostat housing or the pipe coming off the housing going to the block.



What else could be leaking in that area? No coolant is leaking towards the right side of the bike just the left.
 

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Discussion Starter · #2 ·
Got to inspect it a bit more. Idk how i missed this before but it appears to be a leak at the left head gasket.



I changed the head gaskets less than 150 miles ago. I re-torqued the heads after i ran it for a while but i haven't re-torqued them since then. When I pulled the left valve cover there was a slight milky substance in the upper part of the valve cover. Both of them had this slightly but the oil on the dipstick appears to be free of coolant. I know the milky substance could be coolant mixed in with the oil but i have also been told that when it gets colder like it is now, condensation can happen inside the aluminum head and valve covers causing the milkiness.



Should i pull the heads and make sure the surfaces are clean or just try and re-torque and see if the leak is fixed?
 

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Tough call. I would probably clean up the area and retorque everything and see what happens.



Did you use honda head gaskets or aftermarkets and did you replace the coolant orings in the process? An exterior coolant leak and not in the oil seems more like it isn't the head gasket.
 

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Discussion Starter · #4 ·
I did use Honda head gaskets. I did not replace any o-rings. The leak doesn't appear to be coming from the tube that hooks to the thermostat and the block. From what I can tell its coming from the back side of the head and leaking down onto the exhaust.



I just re-torqued everything and still have the leak. I can not see where its coming from at all but if I cant figure anything out ill pull the head i guess and have a look.
 

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Someone posted a trick here a while back.

Clean and dry the entire area then dust it with common flour. Start the bike and watch closely.
 

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I've been on this forum for several year now and every now and then, people get bad head gaskets. Usually the bad ones are some no brand Chinese knock off but you never know.



I'll conjecture that the milky stuff inside your valve covers is the result of coolant leaking, not any theoretical condensation. I'd take it all apart, clean the mating surfaces and then use Permatex head gasket sealant in addition to the head gasket. Torque it all down properly.
 

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My 2nd engine had leaks at the t-shaped metal pipe that enters the engine, the same one that comes off of the radiator hose. 2 new rubber 0-rings and life was good.



I may not be understanding you correctly, so take it for what it's worth.



~Thom
 

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Discussion Starter · #8 ·
Thanks for the Ideas. Thanks for the tip marshal.



I guess when I get a chance I will pull the head and make sure I didn't just get gunk or something stuck in between the mating surfaces. When I use the head gasket sealant should I just brush it on like i am told to do for the valve cover gaskets?
 

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Discussion Starter · #9 ·
And I will check the o-rings as well. I was going to replace them but for some reason didn't get around to it before I put it all back together.



I haven't had much time to work on it way to many papers to write. Seems like all I get done anymore is Work, Class, and Homework.
 
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