Losing coolant, but how?!

[ohsnap!]

Hey guys,
I've had the car warn me of low coolant twice now about a week apart and have had to top up the coolant by almost a litre each time. There are no visible leaks on the floor and the engine bay looks fairly dry apart from some oil so I'm confused as to where the leak could be. I'll be checking the hoses tonight to see if there are any leaks but I'm guessing if it was a crack/split hose it'd be a lot more noticeable... Is it possible the coolant cap might not be sealing properly so it's venting out through there?

So many dramas with this car at the moment, it makes me sad :<

[gazzmo]

Which engine is it?

Have you looked under the oil filler cap for any sign of white drops amongst black oil?

[2000MN]

Another point to check will be the O-ring that seals the Coolant sensor.

[Umai Naa!!]

Have it pressure tested. It'll show up sooner or later.

[JustCruisn]

A small leak may not be noticable when the engine is cold. As the coolant heats up and the pressure rises it can be forced out a small leak but will vapourise, you wont see any pooling.
Look for pinkish powder around all joints.

It is common for the junction at the end of the engine block with the sensor, above gearbox, to crack.

[dylan8]

A small leak may not be noticable when the engine is cold. As the coolant heats up and the pressure rises it can be forced out a small leak but will vapourise, you wont see any pooling.
Look for pinkish powder around all joints.

It is common for the junction at the end of the engine block with the sensor, above gearbox, to crack.

This. Mine didn't even crack but warped off the block, it was only a tiny leak when hot, didn't leak once car had been parked and cooled

[Umai Naa!!]

Yeah, and if you've got a cam cover leak, the oil will seap down and cause the o-ring to swell.

[ohsnap!]

yikes, thanks for the tips guys, will take a look over the weekend to see if any of the above applies. hopefully it's nothing serious though, there's enough wrong with the car as it is!

[ohsnap!]

This. Mine didn't even crack but warped off the block, it was only a tiny leak when hot, didn't leak once car had been parked and cooled

Looks like this is the culprit, took a look and there's a load of fluid sitting on my gearbox now and I can see coolant dripping down the side of the hoses.

Any idea what the part number for the junction is? Need to try and chase up some prices, etc.

[dylan8]

Not sure sorry as a mate hooked me up with the part/install.