Hi i have a 96 classic impreza and i have a overheating problem, coolant is bubbling from overflow tank and expansion tank, ive changed thermostat its heating up to halfwy temp, fan kicks in then coolant bubbles like mad. I also have no heating stone cold. Exhaust smokes white and water in exhaust. Please help im dreading the head gasket failure

 

Sounds more like an airlock.

First off, go to a reputable garage and ask for a "sniff test". It tests for hydrocarbons in the coolant, which, if found, are a sure sign of head gasket failure.

If that is ruled out, have you had any work done on the cooling system? Coolant change? hoses?

If you simply refill from the header tank, chances are you'll airlock it. Do it my way: https://www.scoobynet.com/general-te...-question.html

If the above aren't the problem, your coolant pump may have failed. I've known of instances where the impeller falls off, or becomes loose on, the shaft. The pump appears to be turning, but does nowt.

And lastly, please be aware that OVER-heating isn't usually a sign of thermostat failure. Thermostats almost always fail OPEN, not shut, to avoid overheating. UNDER-heating is a sign of thermostat problems. Overheating is a sign of airlock, coolant pump failure, or head gaskets resulting in low coolant level.

 

Replaced rad for bigger uprated one and renewed all coolant hoses ive tested water pump and its pumpinv out when i removed top hose of rad. How do i justify airlock. Where do i start as i heard they are quite tricky to resolve thankyou for your help aswell

 

Also i had water spraying out of d/v when revving but no visible water in turbo

 

Only one way if it is an airlock: to be sure, drain and refill like in the link I posted. Forget bleeding it, it's not 100%

And with your other symptoms, get the sniff test done before doing anything else. Cheap as chips, will tell you in minutes if the hg's have gone.