This morning while sitting idle at the airport, I watched the temp needle almost hit the "H". So after a long drive on the highway with heater on full blast, I popped my hood and found coolant all over the side of my block where the block code is. It's hard to tell whether or not it's a mixture of oil and coolant. I already had an oil leak of some sort in that same area...now there's coolant in the mix. There's no white sludge under the oil cap or any indication of coolant in the oil (so far).

The thermostat is definitely shot. The lower radiator hose is cold to the touch at idle normal operating temperature and the fan doesn't turn on. New thermostat and fan switch are going on today. I checked the other hoses and did not come across any leaks. Radiator and overflow bottle were dry. I refilled them and found no leaks on the radiator or anywhere else after driving.

Would a faulty thermostat contribute to coolant all over the side of the block?

If the headgasket is blown, how bad would the damage be if it's only leaking towards the outside (if thats even possible)?

It's a B18C5 FYI. Any help is appreciated.

 

Sounds like the thermostat is stuck closed if the lower hose is cold at normal operatiing temperature. Is your overflow tank full?

 

The overflow tank was bone dry.

 

fix it soon. sounds like a thermostat to me also. also, if you later blow a headgasket and do a headgasket change, check for flatness on the bottom side of the head for any warpage.

 

Changed the thermostat and fan switch the other day. I start it up the day after and go for a short drive for some grub. It started to overheat after 15 minutes or so. After some examination, I found classic signs of a blown HG: milky substance under oil cap, trace amounts of oil in the coolant, etc.

Great.