Air bubbles (foam) on dipstick??

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Kernal

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Air bubbles on dipstick??

Does anyone out there routinely see any air bubbles on the engine oil dipstick when you check the oil level? It's not water, a recent oil analysis came back good, no water, coolant, or fuel. Using same oil as always. Adding a photo to show what it looks like immediately after shutting down, engine fully warm after a drive. When I first checked it tonight there were less bubbles so restarted and held the rpm's up at 2000 for maybe 20 seconds and rechecked.
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Occasionally I will see tiny bubbles. Nothing of concern.
 
Thing is I never saw air bubbles before IIRC. Did some reading, a few common causes are not enough anti-foam additives in the oil, particles in the oil (allowing a bubble to form around them), contamination, air getting sucked into the system (loose connection in the pick up tube or elsewhere in the oiling system??), among others.
 
Tiny Bubbles?

Engine warm or cold?

'tis the season for minor condensation.
 
Been seeing the bubbles for a few months, most apparent after running the engine and immediately after shut down. If I wait the very small bubbles appear to coalesce into fewer larger bubbles. They also tend to be more on the unhatched side of the dipstick, which always is 3/16" lower than the hatched side assuming the dipstick is inserted so that the words on the handle (Engine Oil) are right side up.
 
I did put in an additive a few thousand miles ago, and figure that the bubbles may be due to the Ceratec (Boron and Moly) which is upsetting the anti-foaming additives in the oil. Don't want to dump the oil out just yet to test the hypothesis, it's only got 6000 miles on it (Mobil 1). An engine oil analysis I sent in last week came back with no surprises; no water, coolant, or fuel, but as expected it had more Boron and Moly. I've also noticed extremely small specs of a ?precipitate on the dipstick which I'm pretty sure is that additive. The obvious answer is that the additive is likely causing the bubbles but wanted to see if others ever saw them on the dipstick. I wrote the company in Germany (Liqui/Lubro Moly) and they said no, it won't cause air bubbles or sludge, but I'm now thinking they're wrong.
 
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I run the Mobil 1 15-50. no problems, no additives, no bubbles. I would not worry about it. Just run it out til you are ready to change it next time. Try running no additive and see if that makes the bubbles to away. John
 
Yeah, that's my plan. I mix different weights of Mobil 1 depending on the season or what I happen to have on hand. About 4-5 quarts is Mobil 1 5W-40 Turbo Diesel Truck with the rest usually 10W-30 Mobil 1. I generally don't use additives but this one seemed a bit less snake oily than the most.
 
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Sounds like you have quite a mixture going on in your engine ...

If there is too much oil in your engine, the crankshaft can contact the oil in the oil pan and cause it to foam.

The foam is not good as it will diminish the lubricating ability of the oil if it circulates within the engine with foam/bubbles in it.

If it were me, I'd dump the oil mixture you have currently and replace the oil and filter with one grade of quality oil - no additives.
 
I've mixed different weights of Mobil 1 engine oil previously with no air bubbles, that's why this appears to be different, probably from the additive but wanted to see if any others saw bubbles on the dipstick immediately after shutting down the engine. The dipstick shows just less than full in a warm engine.
 
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Kernal said:
The dipstick shows just less than full in a warm engine.
Click to expand...

That's with the engine off after having sat for about 5 minutes, right?
 
Back to the original question; does anyone see bubbles in their oil (after shutting down a warm engine), large, small, always, sometimes, never??
 
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Never, on any engine I've ever had. I'd drop that oil and replace ASAP if it was my vehicle.
 
I'll get another photo, it isn't as dramatic as it sounds, just some small bubbles on the dipstick, not like the head of a draft beer.
 
Kernal said:
I'll get another photo, it isn't as dramatic as it sounds, just some small bubbles on the dipstick, not like the head of a draft beer.
Click to expand...

Pics could help clarify what you're dealing with. Bubbles are one thing, but foam is another!
 
Took photos and now can't find where I put them, will get another. Did an engine oil analysis one week ago after running this oil 6000 miles, came back perfect, no unusual wear, no water, no significant insolubles, etc.
 
I didn't read all the posts so sorry if its been brought up, but I remember my hs auto shop teacher telling us that engine oil will get frothy if you've put too much of it in there. Don't know if that helps at all but just thought I'd throw it in there.
 
Added a photo to the original post; not the expert but after searching and reading I'm aware of some causes of air bubbles, including over filling, sucking air in the system, contamination, not enough anti-foaming additives, particles of dirt, ---. Apparently they even can be caused when oil passes around a sharp angle inside a galley or port. I recently installed a 90 degree oil filter adapter, but the bubbles were present and have not changed since I did that. Also changed my oil filter a few times (Toyota, Mobil 1) see if that would make a difference, nope. Only thing that might have decreased the bubbles a bit was when I topped up the oil level with a quart of Mobil 1 last week, I'm guessing the extra anti-foaming additives helped with that. So have other people seen air bubbles like what's shown in the photo above?
 
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