So I've borrowed a sniff test kit, warmed car up and done the test from the expansion tank (next to rad) it was bubbling like mad in tank but done the test and it stayed blue? Got a little smoke from exhaust which when speaking to api they said Ringland failure? Should this still return a fail on the test?

 

A broken ringland has no effect on the head gasket and or cooling system. It will however cause the engine to breathe heavy. Pull the dipstick with it running.

 

So would that cause the bubbling in the expansion tank (next to rad)? Also by taking the dipstick out what am I looking for, sorry to sound thick lol

 

You need to understand how a water cooled piston engine works.
You need to understand where the combustion is happening, where the coolant is, where the oil is and what piston blow by is.
Crankcase ventilation and pressure also come into it.
The coolant is no where near the piston. Broken ringland will not have any effect on the coolant system, the rings separate the crankcase from the combustion chamber.

 

ok so in the respect of the bubbling in the expansion tank, im not talking about a little bubble here or there, when the running temp is up I've got water to the top of the tank (from top filler level) bubbling and sometimes spilling form the top. so if its not exhaust fumes causing the bubbling, it must be the head gasket gone causing it surely? PS this is a 2.5 wrx Hawkeye

 

Doesn't matter what engjne it is, the principals are the same for all water cooled four stroke piston engines.
Bubbles in the header tank with the cap off? Or bubbles in the expansion tank?

 

ive got bubbles in header tank with cap off (almost like foam frothing out of top) and if I take the cap off the expansion tank it bubbles fairly constant once warm . over the last few days ive had it smoking a little (blue ish from exhaust) when idling and it will smoke a little (30 secs) then clear for a while and repeats itself, and it stinks too when pulling up at junctions

 

There's your problem then, at normal operating temperature the cooling system often reaches temperatures above boiling point.
From physics at school you should know that when a liquid is subject to pressure it's boiling point is raised. That's why a cars cooling system is pressurised, to raise it's operating temperature.
If you take the cap off it will boil, the bubbles you are seeing are water gas, more commonly known as steam.
Maybe it's overheated and cooked the head gasket after being ran with the cap off fkr a prolonged period?

 

ive only had the car for approx. 2months and still have a lot of learning to do lol! the caps haven't been left off for too long, only until operating temperature to see weather its bubbling or not, of course what the previous owner has done I haven't got a clue. cheers for your help im waiting for a call back from api to get the car up for head gasket and rebuild

 

Is it using coolant?

 

a little, I think im topping it up due to it over flowing out of the expansion tank (happen twice)

 

I struggled to get a good sniff test reading from the expansion tank. Even though there where lots of bubbles coming out.

After going for a hard drive and quickly removing the lid of expansion bottle and putting the sniff tester over the hole so that the gas didn't escape I finally got a green reading.

 

yes I did try this, gave it a run up the road and gave it about 15 squeezes afterwards and still no joy

 

Bubble can only be one of two things. It's either over heating and boiling over or exhaust gases getting into the cooling system.
If your not geting a positive test with the hydrocarbon tester. And the expansion tank is bubbling over it sounds more like a overheating problem.

When my head gasket went on my old hawk I never got any over heating. Just little bubbles coming up in the expansion tank after a hard drive.
And a watery noise behind the dash when revving the engine due to a air lock in the heater matrix.

When the car was started from cold with the header tank lid open there was also thousands of tiny bubbles in the coolant

 

The temp gauge goes to half way on the dash, only twice in the 2 months it's gone the whole way to the top and that's when the expansion tank has over flowed. Surely if the engine is overheating it would display in the dash?

 

Sounds like you hae cooked it, all the way to the top is waaaay too hot

 

When it happened the first time, I put the heaters on straight away and pulled over and let it settle, headed home and it was fine till about 3 weeks after it randomly done it again... so once again pulled over let it cool and got home. Hasn't done it since but when it did over heat it was boiling over out of the expansion, so posted on here about it which most of the responses were "do a sniff test" which annoyingly in some respects have come back stating no hydrocarbons detected. I'm just going to have to get it to api and let them do what they do best.