Moisture under the oil cap...
Thread Starter
Instructor
Joined: Dec 2005
Posts: 101
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Moisture under the oil cap...
Does moisture under the oil cap always mean head or head gasket issues?
I just had the heads professionally rebuilt, checked, & new Head Gasket installed. I brought it in because there was signs of a blown gasket (white smoke from exhaust, white milky substance under oil cap, & coolant kept going down). When they took it apart....it was bad.
I've had it back for two weeks & it runs great. The temp runs normal, no white smoke from the tailpipe, the coolant levels don't move & is always full.
Today I removed the oil cap cover when I just got home. There was like condensation on the under side but it was like a dry grayish look. Didn't look like white so much. I put the cap back on and went about my business. I went back to check the car again about 20 minutes later because I forgot to check the oil levels (which looked good....no white substance). Checked the oil cap again & just seems like condensation on the bottom of it.
Any suggestions...or is this pretty normal?
I just had the heads professionally rebuilt, checked, & new Head Gasket installed. I brought it in because there was signs of a blown gasket (white smoke from exhaust, white milky substance under oil cap, & coolant kept going down). When they took it apart....it was bad.
I've had it back for two weeks & it runs great. The temp runs normal, no white smoke from the tailpipe, the coolant levels don't move & is always full.
Today I removed the oil cap cover when I just got home. There was like condensation on the under side but it was like a dry grayish look. Didn't look like white so much. I put the cap back on and went about my business. I went back to check the car again about 20 minutes later because I forgot to check the oil levels (which looked good....no white substance). Checked the oil cap again & just seems like condensation on the bottom of it.
Any suggestions...or is this pretty normal?
Drifting
Joined: Mar 2002
Posts: 1,251
Likes: 2
From: Thomson Georgia
It could be some seepage from the head bolts. Doesn't happen often, but it does. It's caused by the threaded bolt holes are open to the water jacket.
I would pull the bolts loose, one at a time, and use a sealant, and retorque.
I would pull the bolts loose, one at a time, and use a sealant, and retorque.
Drifting
Joined: Jun 2001
Posts: 1,625
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From: Zagreb, Croatia
Melting Slicks
Joined: May 2007
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From: Warwick RI
Thread Starter
Instructor
Joined: Dec 2005
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Fortunately, I live 4-5 miles from work….unfortunately, the car never gets warm enough or even above 173 before I get home. It has a 180 temp stat installed so I barely get any heat (warm air) by the time I get home.
I did some reading here & there and some people are saying it’s normal because the car is not getting hot enough (or running long enough) to burn any normal condensation inside the engine.
Thinking about it....I doubt the car is even running longer than 10 minutes.
I did some reading here & there and some people are saying it’s normal because the car is not getting hot enough (or running long enough) to burn any normal condensation inside the engine.
Thinking about it....I doubt the car is even running longer than 10 minutes.
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Verdad Gallardo
Team Owner
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Given the short trips, you should try to drivie the car for about an hour at freeway speeds. Let everything get to operating temp especially the oil temp. This should get the crankcase hot enough to remove excess moisture. Chances are what you are seeing is some remaining condensation from the earlier head gasket failure.
Check under the cap again after the car cools completely (like the next morning) and see if the stuff is still there. You can always drive another one hour stint to further help dry out any remaining condensation.
Not letting the fluids get to operating temp will keep condensation in the crankcase and eventually build up sludge. You will also get moisture in the exhaust system which will cause corrosion.
Check under the cap again after the car cools completely (like the next morning) and see if the stuff is still there. You can always drive another one hour stint to further help dry out any remaining condensation.
Not letting the fluids get to operating temp will keep condensation in the crankcase and eventually build up sludge. You will also get moisture in the exhaust system which will cause corrosion.
Race Director
Joined: Oct 2005
Posts: 11,772
Likes: 177
From: Rolla Missouri
2021 C4 of the Year - Unmodified Finalist
St. Jude Donor '10 thru '25
The condensation is never being evaporated off.
I am in the same situation as you, and at least once a week I will actually take a longer way home, so I can get the car up to operating temps.
And keep in mind that the oil temp will take longer to get up than the water temp. A good 15-20 mile drive before the oil temp gets up in the winter.
Thread Starter
Instructor
Joined: Dec 2005
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Yep, those conditions are about the worst you can put your car through.
The condensation is never being evaporated off.
I am in the same situation as you, and at least once a week I will actually take a longer way home, so I can get the car up to operating temps.
And keep in mind that the oil temp will take longer to get up than the water temp. A good 15-20 mile drive before the oil temp gets up in the winter.
The condensation is never being evaporated off.
I am in the same situation as you, and at least once a week I will actually take a longer way home, so I can get the car up to operating temps.
And keep in mind that the oil temp will take longer to get up than the water temp. A good 15-20 mile drive before the oil temp gets up in the winter.
but the short trips can do harm.
Race Director
Joined: Oct 2005
Posts: 11,772
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From: Rolla Missouri
2021 C4 of the Year - Unmodified Finalist
St. Jude Donor '10 thru '25
The same can be said for the guys that store their cars through the winter. Some of them want to go out and start them and run them for a bit once or twice a month.
If you only storing the car through the winter months, unless you can drive it for a good 15-20 miles your better off not even starting it. Putting the away for 4 or 5 months during the winter is not long term storage.
Safety Car
Joined: Apr 2004
Posts: 4,532
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From: Lahaina Hi
Change the oil and filter again and put some good oil in it ,not that mobil one crap.
Try the Vavaloine racing oil for a 2k oil change and that should clear it up.If they used the wrong sealent on the head bolts you have a problem.
I use the B2 formula from MR gasket on the Ltx motor head bolts.
You can also get that milky look in the valve covers if the intake bolts need retorking (leaking waster).
When your engine was new GM installed some sealent crap in the radiator to seal the bolts from the factory,I for get waht it is.
Try the Vavaloine racing oil for a 2k oil change and that should clear it up.If they used the wrong sealent on the head bolts you have a problem.
I use the B2 formula from MR gasket on the Ltx motor head bolts.
You can also get that milky look in the valve covers if the intake bolts need retorking (leaking waster).
When your engine was new GM installed some sealent crap in the radiator to seal the bolts from the factory,I for get waht it is.
