How serious is this type of HG failure?

[platofan]

It's combustion gases displacing coolant and coolant being lost through the header tank due to pressure.

I have no other symptoms but was wondering if I should be ok in regards to cracked/warped head/block as the car doesn't overheat, it just loses coolant and is refilled before it has the chance to get that low.

I'll be looking into prices for a new HG as of today. Water pump and cambelt were done just last week as a first step but I didn't realise the coolant was being lost through the overflow.

No loss of power
No smoke
No oil in water/vice versa
No overheating
Idle seems ok
Starts perfectly

Infact you wouldn't know it had a problem if it didn't loose coolant. I suppose that's why the little who sold it to me got away with me buying it. Had the car 2 months and this has been there since day 1. It's also not an airlock lol.

It's an ASZ 130 tdi. Looked into a new engine but it's too much hassle for a 53 plate Ibiza with 107k on the clock. If I can't sort it then that's 4k down the pan after i've bought brakes, new tyres, alloys refurbed, serviced, cv boot etc.

Thanks

 

[MJ]

Have you definatley had an exhaust gas to coolant cross contamination test done? this would verify your suspitions straight away.

 

[flappy]

Or a compression test accross the cylinders?

 

[platofan]

Well had a sniff test done when it was on idle, it came back ok but I don't think it was hot enough. It only seems to spit itself out of the expansion tank when it's up to temp and it's getting revs. e.g motorway driving means big loss but driving around town in this weather doesn't really show much.

Don't know what else on earth it could be.

 

[MJ]

Not a sniff test, a cross contamination test where you take a sample of coolant, pour it into a container, add the other chemical and if its contaminted with exhaust gases then it changes to black, if not it stays the origional colour. This is an easy way of getting a certain definitive answer.

 

[platofan]

Ok i'll look into that thanks.

Still have no clue of where the pressure is coming from though.