Hi guys, hope you are safe in the current health crisis.
Soooo, I have a 1997 Impreza Turbo 2000 with some overheating issues.

Was on a routine sunday drive when the temp started increasing and the heaters blew cold, once I rev the engine slightly the heaters blow hot and the engine temp drops which confused me, so I turned off waited for an hour, then opened header tank which was empty and the expansion tank was full, looked under the car and there was a pool of coolant directly under the passenger side.

filled with coolant and drove home, en route the same thing happened when driving out of boost threshold there is no issues, once entered boost and come to a stop the temp will increase and heaters go cold, rev engine the heaters blow hot again and engine temp decreases.

Car has had thermostat and coolant changed 1000 miles ago.

I have read many threads but none have had exact issues I'm having, if this is a HG issues what is recommended on a Classic just a HG or a rebuild.

Help me..... HELP me... ScoobyGurus!!!!!!

A big thank you in advance, next time a subaru flashes me I will flash back and not ask my wife "do you know him"? Haha

 

Usually air pushing water out of the cooling system would show as HG blown, as the cylinder pressure when on boost at compression stroke is higher than coolant pressure and will push air/fuel mix into the coolant chamber. When not on boost will most likely be burning it off in the cylinder during running. Could be a leak in the turbo seal but only if running boost over 16psi. Most auto stores will have a hydro carbon dip tester to check if there is any fuel / oil is in the coolant then it will confirm a head gasket. Rebuild / replace matters on condition and budget when its pulled down.

 

Thank you for your response my friend.
yes your theory does indeed make sense, needless to say the vehicle has 140k miles on it so a headgasket is expected.

I was just confused about the revving at standstill that brings the tempreture needle down and heaters to blow hot again, also one thing to add I felt the bottom hose it was cold and the top was hot, after revving for a few seconds at 3k rpm the bottom hose started to heat up, but then if left idling it began to go cold again after 10 minutes, is this a normal operation of the thermostat? Or do both top and bottom hose be hot on a normal operating engine?

I have a budget of 3k pounds sterling, to your knowledge what could this get me?
Kind Regards

 

Your head gasket has likely failed, and only a strip down will tell you what further damage has occurred, and what you need done. Whilst you can get a head gasket replaced for less than that, it is considered a false economy, as main bearing failures frequently occur within a year. There are cheap rebuilds for around that price, but a decent one by an established reputable builder will be 5k or more.
The coolant change that you had possibly caused an airlock, especially if not done by a Subaru specialist, which accelerated an existing problem. Definitely don't drive it further until it is investigated by someone who deals with Subarus all the time

 

I see, any recommendations on a specialist? I'm from the midlands.

 

I'm assuming there isn't any water pooling on the top of the block. I've had coolant leaks from the water cross over pipe seals before.

 

Subaru coolant conditioner time?
Apparently it's Holts Radweld. Plenty info on youtube. If your Scooby is nearing 90k miles it's a good idea to treat it to a dose.

 

wouldn't put Radweld in an old rusty lawnmower.............