2006 Sportsman 500 EFI coolant leak

[rcpd_outlaw]

My buddy has a 2006 Sportsman 500 EFI. We got the thing stuck in a ton a mud a couple of weekends ago and a coolant leak has developed. He tore it appart and found there is a hole behind the casing where the thermostat is on the right side of the engine. It appears to start leaking out of that hole at a good pace when what appears to be when the thermostat opens to let coolant into the engine, after the engine has been runnig for a while. We are not sure what this hole is for, as it appears to supposed to be there. Anyone had issues like this in the past or any advice as to what to do next? Like I said, the hole does not appear to be cause by a rock or anything, it appears to either have been drilled or molded into the casing.

Thanks!

[parttime]

that hole is the wheep hole it lets you know that you need to replace the water pump seal.