Likelihood of HGF?

[Flossy]

Just been sat in the car with my Mrs, she drives a Jimmy which has not long ago had its head gasket done. Been sat in traffic and slowly watched the needle rise, whacked the heaters on. Then as soon as we saw steam we switched the engine off and cracked the bonnet and waited for it to stop. Having not really dealt with this before, what's the likelihood of the gasket having blown again?

[twosmoke300]

Prob a stuck stat - the likely cause of the original hgf but not fixed

[Flossy]

Thats what I'm hoping- I replaced the stat before it finally went in thinking it couldve been that causing all the coolant to vanish. After the work it seemed to be behaving but last week I checked the fluids and sure enough, low coolant. I think it's going to have to go back to the garage. What I'm unsure of is if steam escaping from the engine shows the head gasket gave up

[Flossy]

As an update, I've just got back to the car and looking at it now it's ad a while to cool down it seems the steam was coming from the area to the left of the block which is where the stat is, and the expansion tank has a healthy amount of coolant in it so the rad wasn't totally empty. So stat is definitely the next thing to look at!

[Guest Hooli]

Steam normally escapes from the cap when the pressure in the cooling system is too high. If it's coming from elsewhere you've got something not sealing due to a crack, gasket or not being refitted properly.

[dollywobbler]

Are the cooling fans actually running?

[Flossy]

Couldn't say for certain on the fan as I was a bit panicked when we stopped and wasn't paying proper attention. I will give it a run tomorrow in calmer conditions and try to diagnose the situation properly