250F Going crazy!!!! 06yz250f

What's up peeps I have an 06 yz250f just rebuilt the top end piston,rings,valves and springs. All valves are seated I have compression. As soon as I put engine ice antifreeze in it it goes straight into the jug (cylinder) causing the spark plug to become wet from the coolant. I have checked the water jacket in the head and replaced the head gasket 3 different times just bought another head gasket a couple hours ago to try it again and still same outcome so make that 4 head gaskets I'm getting ready to burn the thing :foul::foul: any input would be awesome thanks guys!!
 
So I'm guessing this only started after the rebuild. If this is the case it may be a warped head. I have seen heads overheat and warp but not show it until unbolted. Check the head and cylinder deck with feeler gauge and a straight edge. Not sure of the tolerances but I wouldn't want too see any more than .00015"
 
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Thanks for the input. I didn't even think about that. I'll check tomorrow and if that's the case see what lapping the whole head will do if not buy a whole new head
 
Well checked to see if the head was warped turns out it wasn't used a straight edge and feller gauges still going to take it into my work to have one of the shop guys use a surface grinder on it for safe measures. In the mean time any other ideas ? Cylinder is also good
 
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I've had the same trouble on my early 90s crs all I had to do was change head gaskets to the cosmetic gray asbestos looking 1s need more material between head . Who ever try's to deck the head needs to know how to handle aluminum
 
Ok fellas I'm getting my head resurfaced. Now I know it will raise my compression will I need a high compression piston? Right now I just have a wiseco its not a high compression tho
 

SRAD97750

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Ok fellas I'm getting my head resurfaced. Now I know it will raise my compression will I need a high compression piston? Right now I just have a wiseco its not a high compression tho
The decking will raise the compression for you. You will not need a HC piston, as that would compound the increase and possible have clearance issues.
I would give it a compression test and as long as it's not over 200psi, you're good to go on premium pump gas. -BIG DAN:thumb:
 
The decking will raise the compression for you. You will not need a HC piston, as that would compound the increase and possible have clearance issues.
I would give it a compression test and as long as it's not over 200psi, you're good to go on premium pump gas. -BIG DAN:thumb:
Awesome thanks man!!
 
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