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Crf puking coolant help!

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So I have a 2010 250r it has a big bore kit on it . andwent to the track the other day, rode hard all day and at end of the day I pull off the track. Let off the gas and it just died. Then tried to start it and gray smoke was coming out the exhaust. I push it back to my truck, I let it cool down and checked all fluids and trans and motor oil were right on but my coolant was bone dry. I did not realize I was loosing coolant. It still has compression, but I hope I didn't grenade it! I was thinking a blown headgasket. Water pump operates fine. Nothing from weep hole.just seems like the bore kit is boiling the coolant over and puking out the over flow. I want to diagnose this first and get feed back from you guys before I just throw money at it you know? Any advice would be greatly appreciated! Thanks

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Absolutely, but you won't know anything until you take it apart. It is possible to have a head gasket leak into the cylinder without contaminating the oil, but it is usually a small leak.

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Thanks for the info, I'm gonna try to put some engine ice in it them try to start it, I'd it doesn't I'm gonna tear her down and take a look. Hope I didn't grenade it!!!!

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The head gasket separates three things: oil, water and compression. If it fails you can have any combination of the three mixing. Most commonly it's compression into water as in your case.

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Even though it has compression?

 

Yes, even a slight leak of compression into the coolant will cause it to overheat. You won't  nessesarly notice it with a compression test , but  when it's hot and on the power stroke theres huge pressure in the cyl. which will blow hot gasses into the coolant if the seal is not perfect/

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Even though it has compression?

Think of it this way- a compression test shows about 180 psi, right? But when the fuel/air charge is ignited, it produces about 1500 psi at WOT. Obviously, the ignition charge is more likely to bleed a little bit of pressure into the cooling system with a leaky head gasket and you'll never see it on a compression test. 

Applying shop air to the cylinder via cylinder leak-down hose will usually show bubbles or a rising coolant level though. In addition, a combustible gas sniffer will detect exhaust gasses in the radiator. Most automotive and bike shops have this equipment, so if in doubt it might be worth a few bucks for a diagnosis.

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Thanks for the info! Greatly appreciated. Tried to start it today pulled the plug and no spark. Plus its fouled wet and black. So its Def gotta be leaking. Shouldd I get a base gaskey as well? Also would over heating damage a plug? This is my first four stroke. Had it bout a year but this was the second ride after three heat cycles and break in

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