Head gasket?

[wigs_1]

Having a small issue with a leaking coolant. Thought it was either a dodgy valve or a head gasket.
Coolant tank and valve replaced, minor leak on lower hose, but it got me to work and back (75mile return).

Still having s couple of issues but I think I may have caused them, need to let the car cool and reset all levels overnight, however, my question is:

Is the only way to over pressurise the coolant system a leaking head gasket?

Also, if it is the head, how much to fix?

Car is a 51 plate, 167k and will need new rear suspension bushes for MOT. Current train of thought is if the head gasket is gone it's probably not worth fixing.....

Any thoughts welcome, thanks

[SammoVWT]

I've had a pin-***** hole on my lower radiator hose before - would vapourise the coolant when it was hot, didnt even show a leak. But it would let air in when it cooled down, I only discovered it by chance when I went to pick up a new ignition coil when I went on a very short run when the car was cold. A bad expansion tank cap can not hold pressure and allow coolant to expand out the top of the tank rather than holding pressure had this also too.

Whether its worth fixing depends on how reliable the rest of the car has been and what else its been through. As long as its not overheated or lost oil then its perfectly salvageable, will just be a head off and a new gasket, possibly a head skim. With no complications I can't see it costing the earth. Depends on the engine though and how bad it is.

Could even be a gasket leak going outside the block, but that's usually visible. You've put a lot of miles on it already, for me its a case of better the devil you know, but I can't make that choice for you as I don't know what the state of the rest of the car is.

[Crasher]

A PD TDI then?

[rowdy-999]

You don't say what engine it is? You can get a pressure test or a more accurate 'leak down' test.
There are some cheap and cheerful additives you can use to fix head gasket issues. I've known engines run for a few years with a repair, others the fault reappears soon afterwards.

[wigs_1]

It's a PD TDI.
No water in the oil. Engine runs fine. Never overheated, needle never moves past 90. Only ever had to top the bottle up, never had to fill the whole system.
New thermostat in the last 12 months.

First sign of problems was the morning after the hottest day of the year (reached a dizzy 28degC here in Scotland). Basically lost a coolant bottle worth of liquid. Engine bay damp in places underneath the bottle. Only happens occasionally, can drive to work gently at no more than 70 and it's fine. Push up to 80 or load the turbo and it sometimes has a problem....

[MiniMental]

I had this issue two years ago. Kept filling it back up then at Christmas whilst on holiday, radiator burst and had to change it in a car park with a leatherman and a socket set. The ends had rotted clean off. Must have been seeping for months before it finally went. My advice, check it and check it again. Only way to really tell properly is take bumper off and move AC condenser then have a good look at it. Pressure test system when cold should show you if it's not an internal leak. You can easily get it tested for exhaust in coolant at a garage which will tell you if it's leaking there, if it's going anywhere else in engine oil will be a funny colour under filler cap and exhaust may steam.

Just my two cents

Mini