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Coolant leaking from plug blowout hole

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Hey guys, I know there are a few threads on this, but my 03 yz450f is leaking a decent amount from the spark plug blowout whole located on the cylinder head. I just replaced the head gasket hoping that would do anything, but it hasn't. What else could it be? Seals I don't know about? Cracked head? Any input would be greatly appreciated. Thanks! 

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The hole is there to prevent a leaking cam cover gasket from filling the plug well with oil.  There are only two routes by which coolant can enter the well:

1) Coolant in the combustion chamber is leaking past the plug and out (This condition would be accompanied by lots of steam in the exhaust, and the coolant that you would see leaking would more likely look like two-stroke spooge rather than clean coolant)

2) A cracked head

Is there coolant in the oil?

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On 4/20/2017 at 10:33 AM, grayracer513 said:

The hole is there to prevent a leaking cam cover gasket from filling the plug well with oil.  There are only two routes by which coolant can enter the well:

1) Coolant in the combustion chamber is leaking past the plug and out (This condition would be accompanied by lots of steam in the exhaust , and the coolant that you would see leaking would more likely look like two-stroke spooge rather than clean coolant)

2) A cracked head

Is there coolant in the oil?

I think its a cracked head...theres no coolant leaking past the plug or coolant in the oil...well time to rip the head off and take it in to a machine shop...anybody selling a head for an 03 yz450f? Haha

Edited by raabdunn

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On ‎4‎/‎20‎/‎2017 at 1:33 PM, grayracer513 said:

The hole is there to prevent a leaking cam cover gasket from filling the plug well with oil.  There are only two routes by which coolant can enter the well:

1) Coolant in the combustion chamber is leaking past the plug and out (This condition would be accompanied by lots of steam in the exhaust , and the coolant that you would see leaking would more likely look like two-stroke spooge rather than clean coolant)

2) A cracked head

Is there coolant in the oil?

almost certain its there so the plug well doesn't fill up with water, so when you go to take out your plug you don't get a cylinder full of water.

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