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Valve cover vent hose leaking coolant

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Hey have a quick question I just bought a 2008 yz450f and after I ride for about 30min and I stop and idle coolant starts coming out of rad overflow hose as well as a few drops of coolant come out of the valve cover breather hose and the other day I noticed a white cream like mixture underneath the valve cover breather hose after sitting for a few days. Does this mean I have a bad head gasket? Thanks

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The coolant issue is somewhat normal out the coolant overflow especially if you have just  added coolant.  The milky gas smelling oil is also common and referred to as blow-by.  At higher rpms especially, oil gets spit out the crankcase vent while the engine crank case is being displaced and voided of the volume of the piston and connecting rod moving up and down the cylinder.  If coolant is leaving the crank case vent, then you are sure to have it in your oil.  If your coolant overflow tube is hissing out engine  exhaust gas as well as coolant, it is likely you have a head gasket or cracked head.  Often enough people try to run high compression pistons with pump gas and they blow the head gasket.  So if you are new to four strokes and you just bought it, and you put regular fuel in it, then it may have a high compression piston and you need to run race gas, or it is a regular compression piston, and the gasket failed.  I hope rather its just normal and you have no coolant in you vent tube.   Some people dont like the drippings and come up with a catch can system.  Graves, I think makes a recovery system for the the blow by that uses the oil inlet plug to drain the drippins back into the oil, but you better save your pennies.  Please update when you arrive at your conclusion.  Good luck

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Not sure. If it doesn’t at least have 50/50 antifreeze it will boil over easy. Water shouldn’t be mixing into the oil breather. Generally they won’t run if the water is in the head. Check your oil for water. 

High compression with pump premium is no problem. I’ve been running it for ten years. What causes overheating and ruining parts is putting straight water in the radiator then having it boil over and keep riding with no fluid. 

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This is what came out and it has a distinct sweet taste like its partly coolant however the oil doesn’t seem milky on the dipstick but I am going to be doing an oil change asap and will let you know how it looks

5E57B236-F944-4381-9D4F-5FE95C32D0F8.jpeg

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Your problem may be from idling too long. Once at operating temp, you shouldn't let it idle for more than 30 to 45 seconds. If you're sitting waiting for others, shut it off and wait. That's what causes blown head gaskets and cracked heads. I had customer with a YZ426 that cracked the head and it was running down the timing chain cavity into the crankcase.

On another note, lack of punctuation and cap letters makes trying to read your post a little difficult. You're almost there, just a few comma's, periods and caps make a world of difference.

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21 hours ago, MX Tuner said:

Your problem may be from idling too long. Once at operating temp, you shouldn't let it idle for more than 30 to 45 seconds. If you're sitting waiting for others, shut it off and wait. That's what causes blown head gaskets and cracked heads. I had customer with a YZ426 that cracked the head and it was running down the timing chain cavity into the crankcase.

On another note, lack of punctuation and cap letters makes trying to read your post a little difficult. You're almost there, just a few comma's, periods and caps make a world of difference.

Funny how some just can't understand written English without punctuation in this day and age of communication..  Seems weird that the grammar police had to be brought up. especially here. 

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Just trying to help a brother out. Besides trying to figure out what he said, it also affects peoples first opinions of them. Some may not care, but how well you write is the only thing for people to judge you by. It's as simple as that.

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Remember this is a international forum fellows. There are many people posting that speak two or three languages. I find it amazing as many times they write in other languages than their own. 

Edited by SteveThe Snakes
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Ok thanks for the replys so far. I did an oil change ,oil didn’t seem to abnormal, there was a little whitish swirl on the top of the oil after it was drained tho. I did a psi test on the cooling system and I put around 25psi in and it dropped around 3psi overnight. Could it be a small leak in the head gasket? Thanks 

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2 hours ago, logan Warkentin said:

Ok thanks for the replys so far. I did an oil change ,oil didn’t seem to abnormal, there was a little whitish swirl on the top of the oil after it was drained tho. I did a psi test on the cooling system and I put around 25psi in and it dropped around 3psi overnight. Could it be a small leak in the head gasket? Thanks 

You never know. It should leak out quicker and that is a lot of pressure though. You should hear it leak at the head gasket. The first thing to check if the tester is too old or it leaks out the rubber when you screw it on. 

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Even a new pressure tester will leak down overnight. 3psi is nothing. The slight white streaks can be normal and would evaporate within a few minutes of running at operating temp.

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