Loseing Coolant Need Advice !

[krislex]

I have a 51 plate lexus is200 on 124k.. Last week it overheated an i lost literally all my coolant. Didnt go into the red thou, but now every time i fill the coolant up it jus goes. I been told head gasket by a friend, but there is no water oil in the dipstick, no steam or any smoke coming out of the exhaust, heaters are blowing hot air. I have checked the thermostat and its working fine.

Can anyone shed any light on this, as im new to lexus and there may be a common problem or something that im missing.

Thanks in advance Chris

[BenIS]

I know this is not a lexus but my mrs golf v5 had exactly the same problem, like yours the oil was fine as was the water etc. I changed pipes here n there, thermostat, heater matrix, alsorts. until finally i decided to get it pressure checked. Turned out there was a crack in the block and the head gasket had gone. Hope yours doesnt turn out to be this but I would definately get it pressure tested before you start.

Hope this helps

[JohnS Dorset]

Check around the waterpump housing for pinky crusty stuff, check under radiator - how quickly does fluid dissapear?

[steve2006]

Is your cooling system pressurising?

Check the expansion tank pressure cap, they have been known to fail on other models.

[krislex]

Im loseing alot a day, car booked in this week.. When i find out what it is i will post on here, for reference if anything like this happens to your lexus.

[sjrainsford]

A classic cause of coolant loss that seems to go nowhere is the radiator cap. If the seal fails it stops the system operating under pressure. The coolant then boils, so slowly boils itself away.

[sparkystav]

Check your drivers side carpet it could be the heater matrix.

[secam]

Before you do anything, have a good look at the radiator or let a mechanic have a good look at the radiator for you. Sometimes very small leakages in the radiator are difficult to notice. If your radiator is more than five years old then definitely have a look first and check all the hose pipe joints before you start looking at other causes. I had exactly the same problem until a small leakage was detected at the bottom right corner (standing infront of the car) of the radiator. Fixing a new radiator will be less expensive than new engine, head gasket etc. Hope this helps.