Boy this stuff foams... My dipstick shows oil full of little bubbles...never did this with Mobil 1 I don't like it.... Should I be concerned?
Was reading about oil today for the F355. It seems that Shell Helix Ultra has a tendency to do this. I have Agip ENI I-Sint 10W-40 in the car now as it is used by the local specialist here. No bubbling from what I can see.
A motor oil has two tasks: it has to lubricate and it has to cool the motor. In normal motors a lot of oil is splashed against the pistons, cylinders etc. by the movement of the connecting rod. Motors with dry sump lubrication have spray nozzles that spray the oil onto these critical parts. However, this is not enough to extensively cool the motor. Foam garantees that the oil also reaches the parts of the motor where the oil is not sprayed directly. Also gear oil foams to improve cooling. In a gearbox you don't have connecting rods to distribute the oil. The movement of the cog wheels does not agitate the oil enough. (I found this information in a post by user kkswiss in a German Ferrari forum)
Interesting. The PO of my car used Agip exclusively because it was the factory fill for the 348 and I see a lot of small bubbles on the dipstick. It will be replaced with Redline at the next service, since it offers the best specs I could find in the viscosity I wanted and is noted for its resistance to foaming.
This is incorrect in many areas and should be disregarded. It could have unfortunate consequences for anyone foolish enough to believe it. Total garbage.
Might be I put 1.7 litres in a few days ago as the level was at the minimum line. How does overfilling cause foaming?
Hi Mike, I shall look again when I next run the car. I'm quite paranoid about anything other than pure oil on my dipstick so I am sure I would have noticed any unusual or excessive bubbling by now. What spec Redline are you going to go with?
I don't doubt you, which is why I found our two experiences interesting. After just idling the 348 in the garage all the way to full operating temp (water AND oil) I saw lots of bubbles on the dipstick. I'm not 100% certain since I've checked it both ways, but this might have been with the engine running, so if you checked yours right after shutdown that might help account for the difference. But again, my car had just been idling and had not seen any high RPM use before the bubbles were noticed. It was actually that revelation, in addition to a recent problem with my ///M3 track car, that caused me to recently do a good bit of comparison of motor oils in the 0W-40 through 10W-40 viscosity range. The standard Redline 10W-40 has better numbers than anything I compared it to, including pretty exotic oils that aren't easy to get in the US. The fact that I know pro level sports car racers who swear by the stuff helped nail down the decision to run Redline 10W-40 in the 348. For pure track use in the 348 or the ///M3, Redline's 40 weight race oil behaves like a 10W-40 and has even better anti-foming properties, but for now it's not going in the 348 because it's not as well suited for long term use. For street and light track use I didn't find anything any better than the standard Redline 10W-40. HTH.
Of course the oil is foaming in the dry sump systems, very normal. The scavenge pump in the engine sump collects all oil, and a lot of air, and sends the foamy mixture to the oil tank where it settles and the air is separated out (the direction of flow of the incoming foamy oil and the oil tank internals are designed to help the oil-air separation). The main oil pump takes no-bubbles oil from the bottom of the oil tank for the engine lubrication. I would just make sure that the oil level in the tank does not get too low to avoid the possibility of the foamy oil being picked up by the main pump.
Excellent points, Miroljub. But that doesn't mean that anti-foaming properties aren't still important since we want to do everything we can to ensure that there's zero air in the pressure side of the oil system.
I use the AGIP 10w40 to, have the same really small bubble's on the dip stick, Never seen this before, but then again this is my first car with a dry sump.
When I first bought my car, I too, thought maybe that foam was normal for a dry sump car. It's definitely not normal, it's just an incredibly aggravating side-effect of using Shell Helix Ultra, and I find it nearly impossible to get a good clean reading when checking the oil level. I changed over to Redline 10W/40 almost 7 years ago and I've never seen foam in the oil reservoir since.
The only thing foam guarantees is that the bearings will not be able to maintain metal to metal clearances under load.
