sharkbate

I've had to fill up my coolant 3 times over the last 2 weeks. I'm not seeing anything on the driveway to indicate a leak. Thoughts??

John Speake

It's leaking on somewhere hot and evaporating. Look for tell tale traces of dried coolant..... often greenish in color.

chrisjbell

Or its exiting via combustion chambers and exhaust. :-P Either way one of the head gaskets would be a likely candidate... out and hitting the headers or into a cylinder, quickly vaporizing either way.

Mongo

You may have an internal leak of your head gasket. This has happened to me before and had me stumped. As it got worse, I noticed that coolant was being pushed out of the overflow hose of the reservoir since the cooling system was being pressurized by the combustion chambers.

Get a cooling system pressure tester hooked up and pump it up to about 12 psi. If you see the pressure go down on the gauge, but no leaks externally, that is not a good sign.

Has your car overheated before?

sharkbate

Nope. Never overheated. I just the the coolant indicator on the dash.

newworld

lets back it up a bit here......

first, did u recently open up the system hoses, rad, pump etc? before you noticed it going down?

sharkbate

No. The light came on so I opened the cap to put in more coolant.

Mongo

No overheating is a good sign. Can you pull the airbox off and check at the back of the engine? A leaking heater valve is also a likely culprit for mystery coolant loss. However, you would probably smell it inside while driving too, if it is leaking.

Mrmerlin

the two most likely sources are,

The top of the passenger side radiator tank it can leak and evaporate all at once,
look for white crusty deposits on the tank surface of the fins of the radiator front or back.

Next the heater control valve and or short hose, also check the block off plate and the HCV outlet for weeping at the gaskets.

What is the condition of the coolant bottle does it have any cracks in it?
Has the coolant cap been replaced recently?
Do you see any tell tales coming down the center of the top of the oil pan,
this is a water pump leak.

Are the coolant clamps tight at the water bridge and the radiator?

mike77

Might be an idea to check the coolant reservoir cap is on tight and perhaps tighten up any hoses that are easily accessible.

sharkbate

Thanks guys. I'll do some investigating. Appreciate the responses.

FBIII

Check to see if the inside of the oil cap is milky and if there is a lot of condesation.

Chalkboss

I had the same issue. Turned out to be a small leak at the water bridge where it mounts to block. Suprising amount of loss from a slow seep. Look for white crusties.

Stromius

Mine leaked at the O ring in front of the oil filler and had a bad hose between the reservoir to waterbridge that also leaked into the areas.

The Fixer

Look at the res Cap, check it is on correctly and look at the rubber seal.

Get it up to temperature pop the hood and look carefully.