I was told there was a milky film around my oil cap he thought it could be a blown casket

Check for steam-in the exhaust and check for bubbles when the engine is first started. Check for milky appearance in oil dip stick or milky appearance on oil fill cap.

It is likely a head gasket leak.

CHECKING BLOWN HEAD GASKET WITH NO SPECIALIZED TOOLS EASY 4 THE DIYer DO...

When you change antifreeze an air pocket is created in engine behind thermostat. You must let it run until the thermostat opens. Until then, liquid will boil backfkowing through bottom of radiator.
As for milky look, blown headgasket would cause white foam that if left alone wouldclear up. Otherwise it could be an additive in the fluid such as rust preventative.

thats ur head gasket its blown

White smoke is usually burnt water.
Check your radiator water level, if it is down, check for a blown head casket in your engine e.g.(water in the engine oil, or oil in the radiator water) brown froth on filler caps.

milky in the oil cap is ok -- this is caused by condensation and oil mixing inside the oil cap and it is nothing to be worried about.
now if you look at the dip stick and you see a milky looking oil on it -- and if you do a oil change and notice it to be milky - then this is a sign that you may have a blown head gasket, and this you need to worry about.


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Typical symptoms of a blown headgasket may include: -bubbles of air coming up into your radiator (remove cap before starting) -leaking radiator -milkshake colored oil -overheating -rough running -coolant or oil running from head -spark plug(s) that have a green tint (if green coolant). -white colored or sweet smelling exhaust, white smoke of your tail pipe, or loosing coolant through your overflow

Often (but not always), a blown head gasket will also cause deposit of water on a piece of cardboard held an inch from the tailpipe output while the engine is running (when this is happening, it is likely that the catalytic converter has been ruined and the muffler will corrode in short order as well).

Sometimes drops of water will be seen dropping from the end of the tailpipe. Another clue: turn on the heater; often when the head gasket is blown an odor of antifreeze and synthetic rubber will emanate from the heater vents.
Many of the symptoms of blown head gasket can be caused by some other problem in the cooling system, without the head gasket being damaged. Conversely, other problems with the cooling system can cause a blown head gasket and/or warped head.

When checking for a blown head gasket, one of the most common tell-tale signs is a milky-gray ring around your oil cap. When coolant enters the engine oil through a crack in the head or through a blown gasket, it evaporates and leaves a milky ring around the oil cap. Another easy way to tell is to check your oil dipstick. Change your oil and pull out the dipstick. Make sure that you take note of how far up the dipstick the oil is. Top off your cooling system and fill your cooling reservoir to the top. Screw radiator cap back on and start engine. Run engine for about 20-30 mins. or until it reaches normal operating temperature. Allow engine to cool (engine must cool completely to get accurate oil reading!!). Check oil dipstick again. If the oil has a watery appearance and has risen noticeably up the dipstick, the you probably have a blown head gasket or a warped head. Also look for a dripping, sweet-smelling liquid coming out of your tailpipe. Any of the above symptoms could be the result of a blown head gasket. The easiest way to tell is with a compression meter. This replaces the spark plug and lets you know what compression each cylinder is running at. If your compression is abnormally low, then you have a blown head gasket or a warped head. (note: consult repair manual for appropriate compression of each cylinder.)

When checking for a blown head gasket, one of the most common tell-tale signs is a milky-gray ring around your oil cap. When coolant enters the engine oil through a crack in the head or through a blown gasket, it evaportats and leaves a milky ring around the oil cap. Another easy way to tell is to check your oil dipstick. Change your oil and pull out the dipstick. Make sure that you take note of how far up the dipstick the oil is. Top off your cooling system and fill your cooling resevoir to the top. Screw radiator cap back on and start engine. Run engine for about 20-30 mins. or until it reaches normal operating temperature. Allow engine to cool (engine must cool completely to get accurate oil reading!!). Check oil dipstick again. If the oil has a watery appearence and has risen noticibly up the dipstick, the you probably have a blown head gasket or a warped head. Also look for a dripping, sweet-smelling liquid coming out of your tailpipe. Any of the above symptoms could be the result of a blown head gasket. The easiest way to tell is with a compression meter. This replaces the spark plug and lets you know what compression each cylander is running at. If your compression is abnormally low, then you have a blown head gasket or a warped head. (note: consult repair manual for appropriate compression of each cylander.)

It could just be some sort of condensation. I would clean the oil cap well and drive it for a few days. Then check it again. If its a coolant leak it will not go away. I would eliminate the easy stuff before you tear into it.

ceck the engine oil if it is a milky white colour you have blon the head gasket