Morning All,

A couple of weeks or so ago, I changed the coolant hose that goes from the top of the Radiator to the U pipe, to the thermostat. It got through quite a bit of antifreeze before it settled down but it did settle down and the level stayed put for a few days.

However now it has the strangest behaviour.

I do a short 6 mile journey and the level drops like crazy, the header tank is almost empty again today. However yesterday I did a 18 mile journey (from work to my dads then home) and the water level had not budged.

I know the coolant is circulating because yesterday I put tap water in the header tank to fill it up and when I got to my dad's it was blue in colour and not clear.

The carpets are dry in the foot wells and there are no wet patches outside under the engine bay, so my guess is it's an airlock.

It used less antifreeze when it was bloody leaking through the hose lol.

John.

Keep on bleeding John! <br>
Check that you have a good dribble through the thin pipe between the top of the rad and the expansion tank when running.

Hi All,

Well hopefuly I have found the issue.

I took it to the local garage and had a coolant pressure test done (3rd one in 2 months) and the new hose I had fitted it looks like the hose clamp had gone loose and no longer help the hose tight enough so when the pipe got under pressure, coolant was poring out of it.

So in the end it's just a case of replacing the hose clamp with a proper screw type so I can get it goodand tight.

I still can't get my head round the fact that when I pulled up the ground under the car was always dry. If even a few drops were evident then it would have been obviouse but no sign of a leak at all.

Hopefully fingures crossed that is the end of my coolant issues, litterly on my knees praying it's the end lol

John

I was always topping up my coolant with no obvious signs of leaks . It was the throttle body heater plate. Very common fault. I replaced it last year which solved the problem .

It was probably a slow enough leak that the hot coolant evaporated before it hit the ground and then the pipe sealed again as the system cooled.
You can still lose plenty of coolant during a long drive with no visible signs when you stop.
I hate coolant leaks :(

riddlemethis wrote:

I was always topping up my coolant with no obvious signs of leaks . It was the throttle body heater plate. Very common fault. I replaced it last year which solved the problem .

I've already had that issue ha ha but you are right, that was a bitch to diagnose.

Morat wrote:

It was probably a slow enough leak that the hot coolant evaporated before it hit the ground and then the pipe sealed again as the system cooled.
You can still lose plenty of coolant during a long drive with no visible signs when you stop.
I hate coolant leaks :(

I agree mate, coolant leaks are a pain in the ass. I have just bought myself a coolant pressure test kit, got a feeling it will be a very useful tool.

I just put the pipe back together with the new hose clip, I ran the engine with the heaters on full wack, up to temperature with the expansion cap off to start with, let it run any air through, then I fit the cap back on and run the engine for a good 20 minutes.

Results were good, no visible leaks from any of the hoses, the heaters got warm and the engine got up to temperature with no signs off overheating and the coolant didn't drop.

I am going to run the engine up to temperature for a good twenty minutes another 2 times and make sure all is good before I give the old girl the all clear.

Wish me luck.

It does sound like you've cracked it.
Good luck! :)

Had this on mine. Was needing about a cupful to top-up every week or so. I'd just replaced the radiator for an all ally one, all new hoses and stat but just couldn't find where it was going from until one day I'm sitting having a beer and notice, literally, a tiny drop of water underneath. Lifted bonnet, nothing, all nice and dry,
Drove home and before I switched off, got into the bay with a torch which revealed the tiniest fine spray coming from behind one of the clips. it was evaporating almost immediately with a combination of 30 degree ambient + under bonnet temps. On this one occasion however it had dumped just enough to show underneath. Eluded me for weeks that little bastard!