Good afternoon Scooby folk,

I have searched everywhere including google and other forums with no answer for my issue (everything I find relates to oil leaks)

So after hard driving I have a hot metal burning smell, the smell comes in to the car when I slow or come to a stop, The header tank that feeds the turbo always seems to be low and I've not seen the water recirculate from the expansion tank back in to the top tank so I'm thinking my turbo's getting warm and not cooling.

I have filled the header tank up 3 times and put some in to the expansion tank but it still seems to be going somewhere. The radiators always full to the cap, Its had the usual head gasket test etc my heat in the car is nice and hot.

I assume because the waters not going back in to the top tank the turbo isn't getting cool and that's my issue but it only has the 1 return hose and I cant see why it wouldn't be returning. The only thing I could think of is the expansion tank (Behind the front light to the right of the radiator) maybe my hose that goes in there is to long it touches the bottom of the tank and curls round. Should I snip a bit off the bottom? How can I test if that hose is blocked?

Thank you in advance

 

If its a GC8 just a long shot check the steel pipe across the top of the radiator that goes from the header tank to the expansion bottle. They can and do block with corrosion.

 

Thank you for your reply, I have checked the steel pipe I blew straight through it and it was clear.

Does this steel pipe need a constant flow of water through?

 

No the water transfers back an forth to the expansion bottle from the header tank.

 

What car is it and engine size ?
Make sure you haven't got the header tank and rad cap's mixed up - header tank cap has the vacuum valve on it

Mick

 

When i had it running up I didn't really see any movement of the water through that steel pipe? Or is this something that works between hot and cold temperatures?

It is a 2004 blobeye wrx 2.0 turbo.

The Header tank cap is just a standard silver cap no writing on it, The radiator cap I think it says rated to 0.9 bar. That's how they were when I bought the car.

 

The water expands as it gets hot and the pressure releases the valve in the head tank cap and flows into expansion tank. As the engine cools the water from the expansion tank is sucked back in. The header tank cap is a two way valve. When warm the expansion tank should rise and when cold the level should fall. The Rad cap is a one way valve and is a higher rating than the header tank cap. If the pressure gets too high the rad cap valve will open meaning there is a problem. Header tank with genuine cap will have wings and the rad cap without wings on a 2007 WRX may be different on classic.

Your header tank should not need refilling. Where is the water going, must be escaping if your topping up? If no leaks is it getting pushed out of the expansion tank as this is not sealed? Warning, my temp gauge is also useless (not sure if same for classic), I monitor temps with OBD dongle and the temps can get to 105 before the needle even moves and it should not get above 97 if cooling system is working correctly.

 

When I replaced my head gaskets, I found the engine had been worked on by someone who fitted the banjo bolt from the camshaft oil feed to the turbo water supply. Unfortunately that banjo had a filter in it. That would have restricted the water flow and eventually blocked.

 

Just a thought, if you're getting the smell its obviously being drawn in from the engine bay through the heater matrix. Have you popped the bonnet with the engine hot/running and had a look for vapours?

I realise its not the same but smoke from the rocker seals going is blindingly obvious when it goes and maybe you would see where the smell is coming from in this case?

 

I appreciate all your replies I thank you greatly

I found the issue!

It turns out after hard driving the water was seeping out of the feed to the turbo hence why I couldn't see anything, I happened to drive it very hard for a short period of time pulled over popped the bonnet turned a torch on and I just happened to see the water trickling out the end of the rubber pipe where it joins to metal.


Still had the crappy standard hose clips on! Now replaced with a jubilee all fixed no smell and my water's where it should be! Great outcome.

 

Great stuff!

 

Nice one. Glad you posted the solution.

 

It's been on going for a few weeks so glad I found the issue! so I hope everyone shares my joy of finding the issue

 

How old is the hose? It may have hardened with age. I would replace it on suspicion. A failure can be catastrophic.

 

I like your thinking.