I am at a lose here..
I rebuilt my 2010 MXZ TNT 600 Carb last year. Over the course of this winter, I noticed I was slowly loosing coolant from the reservoir and figured there must be a leak around the head gasket as many would suggest its a common place.. I do a pressure test and it does NOT hold 15 psi. So I start pulling it apart and noticed a number of things - the power valves had a small amount of milky oil on both sides, removing the air box found some bright green un-burnt coolant inside, and the carburetor has a green hue colour on the air valves. Digging a bit deeper.. pulling the jugs off and found some brown sort of fluid sitting in the bottom of the crank.
Ok, so I figured it must be leaking at the head gasket, that would explain milky oil on the power valves and some brown fluid sitting in the crank. Using an oil extractor I sucked out the oil and rebuilt the top end with new gaskets using some Dow111 around the head gaskets (Both cylinder gaskets and the outside head gasket). Now I have the sled rebuilt. I take the sled out last weekend and again I am leaking coolant faster than I was before I rebuilt the thing..
Was I looking in the wrong spot? Could I be leaking coolant through the carb into the air box and leaking down into the crank?? I asked the local Skidoo dealer lead mechanic and he couldn't wrap his head around coolant in the airbox. "Coolant in the airbox!???" he says.