Water in, no oil out?
 

My water level slowly goes down, and I sometimes (usually) have whiteish smoke, but I don't have any oil in my overflow reservoir. Is it possible to have a leaking head gasket that lets water in, but doesn't leak oil out into the water?

check oil
 

yes, you can loose oil and not water and water and not oil... so you could be loosing water into a cylinder... or into your oil... or just a plain old water leak..

1. have a preasure test done on the cooling system....

2. Do a compression test....(if your loosing water into a cylinder it will be only one cylinder... and that cylinder will be slugish or dead....)

3. Most likely water would be going into your oil...


if you have water getting into a cylinder then that cylinder is probably not firing and its ejecting water.. and the water is being turned into steam by the exhaust system....

I had a mustang with a really slow radiator leak. Finally we found that the head gasket was gone. This was after a few weeks and multiple pressure tests on the radiator. Do not wait too long. Pull your oil dipstick and look for any water on it. You will get a milk shake brown foam/froth eventually if you take a light and you remove the oil fill cap and look in there carefully. Water is not good at all for wear and it can scuff and score your engines cylinder walls. Whitish exhaust smoke can also be a sign of a failing head gasket. John