2007-03-05 14:37:57 · 10 answers · asked by michelle a 4 in Cars & Transportation ➔ Maintenance & Repairs
It's probably just moisture build up, nothing to worry about. It happens to every car.
However, if this car is driven regularly and happens repeatedly, this could be a symptom of a blown head gasket. Clean it off and see if it returns, if it doesn't, then it's probably nothing. Check to see if there is smoke coming out of the exhaust(be sure to let the car reach normal temp first, because it will always smoke when you first start it up. It's condensation). Check your oil, make sure that it is clean looking, and not milky or foamy, Also make sure that your coolant level is normal and not dropping. You would probably also be overheating, If any of this is the case, then it could be the gasket. oh and if it is the gasket, then the car would probably be running rough.
If none of this applies, then it's nothing to worry about - Just moisture build up.
2007-03-05 14:54:25 · answer #1 · answered by Anonymous · 0⤊ 0⤋
I would like to add that if your car is running fine, then go to a radiator shop and have them do a pressure test of the cooling system. It's a simple test done by putting a small pump in the top of the radiator and pumping up the pressure. If the pressure holds, there is no head gasket leak, which COULD be causing the gunk on the oil cap.
2007-03-05 23:00:00 · answer #2 · answered by Trump 2020 7 · 0⤊ 0⤋
It's a sign of moisture. Either your doing a lot of short trips without to motor getting hot enough or an outside chance coolant is dropping into your combustion chambers. If you're not loosing water / antifreeze in your coolant recovery bottle you have no worry. Do some highway trips occasionally 20 - 40 mile sustained 55 - 65 mph. speeds to heat the motor oil enough to evaporate the moisture. When it's cold out change your oil and filter every 3,000 miles or three months which ever comes first.
2007-03-05 22:59:15 · answer #3 · answered by Country Boy 7 · 0⤊ 0⤋
Oil tank cap or do you mean oil filler cap? On an automotive engine? That white stuff is moisture combined with the oil (white sludge) Gas engines especially those with some miles on them will have move build up than newer engines. Short drives will cause a quicker build up as you havn't boiled out the moisture out of the engine block air.(As all air has moisture(humidity).
2007-03-05 22:48:16 · answer #4 · answered by ButwhatdoIno? 6 · 0⤊ 0⤋
If your talking about the oil fill cap I think it's normal to have that. Almost every oil cap I ever take off has some kind of odd substance on the bottom of the cap.
2007-03-05 22:45:33 · answer #5 · answered by Andrew 3 · 0⤊ 0⤋
The above answers are correct but as precaution check your oil dipstick. Does the oil there look milky also? If so then you may have a blown head gasket or cracked block. Are you having any problems or was this just a curiosity?
2007-03-05 22:49:49 · answer #6 · answered by Never Forget 3 · 4⤊ 0⤋
Condensation from being cold and warming up causes valve cover to sweat mixing with oil to form white or milkish ring on cap.
2007-03-05 22:44:21 · answer #7 · answered by Anonymous · 2⤊ 0⤋
Ringer is right, it sounds like you need to drive your car a little more to get the temp up to avoid condensation build up, changing your oil wouldnt hurt either. This happens to a lot of cars that are not driven much.
2007-03-05 22:46:42 · answer #8 · answered by Anonymous · 1⤊ 0⤋
I'm with all the people that say condensation, and its relatively normal. I have it on my dipstick as well, foamy sometimes, but it goes away as soon as the engine is warm.
Are you in a cold climate? Even more normal... subzero makes it worse..
2007-03-05 23:24:44 · answer #9 · answered by Anonymous · 0⤊ 0⤋
that white yukky looking stuff i swater in your oil.more like blown head gasket or cracked head.has been running hot or losing power?
2007-03-05 23:25:28 · answer #10 · answered by asmanylicksasittakes 1 · 1⤊ 1⤋