Any Tips For Locating Coolant Leak?

Retrogamer

I think it's going to need to be the UV dye method or garage to locate it.

Changed header tank cap. No more hissing, but still leaking coolant quite a bit.

Limey

Had similar issue with my Celica, would lose small amounts coolant when running. I only found the leak when I got under the car with the engine running and everything up to temperature. Turned out that it was a hose clamp that wasn't quite nipped up.

BeenThroughItAll

Retrogamer wrote: »

I think it's going to need to be the UV dye method or garage to locate it.

Changed header tank cap. No more hissing, but still leaking coolant quite a bit.

How have you managed to tell it's still leaking coolant, it's only been a couple of days but you'd said before it took a month to drop from max-min?


If it's losing that much that you can now see in a couple of days that there's still a problem, then I'd expect you to be able to see where it's coming from, or see other signs (steamy exhaust, for example).

Retrogamer

Sorry, i've been an idiot and noticed i left something out on the original post. I must have been half asleep when i wrote it.

Although the coolant leak has been minor for such a long time the last few weeks it's been getting progressively worse. It's losing around half a litre now every 50 miles.

If it's just short journeys it seems to be ok but on long journeys where the engine gets up to temp properly it seems to happen so mostly under pressure.

I'm going to try and take high power torch and have a look around the engine bay for steam tonight after i drive home from work.

Failing that try and borrow a pressure tester and get underneath it for a look around. Failing that then either a garage or UV dye.

Appreciate all the help so far.

Richard53

If you wait until the engine is cold and the block and ancillaries have dried off, have a good look round with a torch from all sides. Often the escaping coolant leaves a stain (pale blue if you have been using normal antifreeze) which gives the location away. That's the first thing I would do, before spending any money on sniffer tests etc. However, if the system is being pressurised it sounds a lot like a failed head gasket.

Retrogamer

As above, no longer being pressurised since cap has been changed but still leaking coolant.

I've slim to no chance of seeing the dried in coolant with my eyes as it's pink (VAG car) coolant and i'm colour blind.
Couldn't get a hold of a pressure tester either so going to take it a long run to get it up to temp, get under it, take of the underside tray and look for leaks whilst trying not to burn myself.

Strider590

Could be the radiator seam? Mine has a minor leak, it took me ages to figure out where it was coming from.

Retrogamer

Just to update on this.

Noticed with header tank cap swapped it's back to a slight hiss when taking it off from cold.
Noticed as well after a long run i can hear a hissing from the header tank area and it's all wet even with the cap tight.
Under header tank is all wet as well.

Checked pipes and they seem to be fine and free from leaks around that area.

Seems to be one of 2 possible issues. Known me, it'll be the worse one....

Header tank is damaged with a crack somewhere so that under pressure the crack opens and it leaks.
I've ordered a new one to check

Or, a common issue on higher mileage PD engines is cylinder head bolts stretching.
Symptoms of that are coolant loss when the engine is under load as when under load the stretched bolts cause a bit of head lift.
Hard to diagnose as when doing a "stiff test" the engine isn't under load so nothing shows up.

Some people have managed to get away with turning the head bolts another 1/4 turn but others have had to have the head gasket replaced with new bolts.