possible blown headgasket

I think I might have a leak in my head gasket. About a month ago I accidently let my car overheat to the red zone on the needle while I was trying to adjust my idle and I quickly shut it off, the overflow bottle was boiling over at this time and I let it cool down and topped back the coolant and it seemed to run fine with no lose in coolant. I have noticed my oil was a little low and now there is oil in my coolant but there doesn't seem to be any coolant in my oil. I also am starting to blow greyish smoke under higher boost.
Under normal driving conditions I don't get any smoke and the needle never goes above the halfway mark so I don't think it is a huge leak, is there an easy way to check a head gasket without pulling the head? it currently has an MLS gasket in there now. Do you think I could have warped anything or have done any other damage when it overheated that one time?
thanks,
ed

 

[rdomeck]

Sounds like a blown head gasket. You almost always warp something when you over heat....... The question is how much? The MLS gasket require a nice flat surface anyway so when you do pull you r head off find a good machine shop to check it for being flat. The warpage limit I believe is .002" overall.

If you have a compression gauge it wouldn't be a bad idea to check that as well. I would suspect you will see lower compression on #4 if any!

 

I'll probably just get an oem mitsubishi MLS gasket and take the head somewhere to get checked out and possibly resurfaced. Can I just ziptie the belt to the gears and should my timing stay put?

 

[fuel]

I had a 4G37 which at approx 250,000 miles decided to let oil leak from the oil gallery into a coolant jacket so had oil sludge collecting under the radiator cap and neck of the radiator but no coolant in the oil etc. Engine was never over-heated and the compression was still at 185psi across the board. I would pull the head and get it checked out for sure. Thankfully in my case the head was hardly warped and with a skim it came up great. It did however bump the compression up to 215-225psi in some cylinders which a few months later made one of the big end bearings fail due to sudden change of load on them.

 

[MuffinMan7580]

Service limit for a 4g63 head is .008", but that's only if you're using a composite gasket. If you plan on using an MLS gasket, .002" is about what I would use as the limit.

 

[Xcelerate]

One way to check is similar to doing a leak down test. First leak down test it and see if youll hear it wistleing in the cooland lines. Another good method is pushing alot of air on top dead center like around 80-100psi, this way you can see or hear better if it leaks in the coolant system. Assuming you know how to do a leak down test!!!