Hi, wife and I bought our son a new CRF 250R for Christmas. He hasn't seen it yet. Wife started it the other day and left it idle. She went inside and when she came back out, it was spitting coolant out the overflow and white smoke from exhaust

. I am thinking at a minimum the head gasket is gone and maybe a warped head. If I drain the oil and find no water, do you think it's okay? Also, I have been reading other posts. If I do a leak down test and no leakage, does it mean we are probably good to go. I am no mechanic but a little handy. Plus, we can't get in to the shop until two days before Christmas. So, I wanted to tackle it myself. Thanks in advance for any help.