R400K Dry Sump Oil

[duncs_c7]

Anyone else find there's small air bubbles on the dipstick when they dip their oil?

[Wrightpayne]

You sure its air and not water?

does it occur straight after running or when its been stood a while and cold?

Ian

[duncs_c7]

Looks like air to me. Well checking the dry sump is immediately after switching off the engine from warm. I was kind of hoping it was just the pressurised system whipping it up a bit!

[Mark w]

Has your tank got a horizontal plate half way up with a big hole in it ?

The purpose of this is to allow the oil to settle before it drops, thus helping to remove the air bubbles .

[duncs_c7]

Look like this (sorry, dont know how to put up photos): http://i.imgur.com/koc3OwN.jpg

[Mark w]

That bell housing tank has a swirl tower .the return oil is returned into the side of the tower . Swirling it round  should take the air out . 

How do you know you’ve got air in the oil ? It’s impossible to see with that arrangement .

What happens if you wipe the dip stick and re dip it ? 

[duncs_c7]

I am not using the dipstick that comes with it, that's next to useless. I drop an alu rod in to dip it. I've never tried to dip it, clean it, and re-dip. I'm not actually sure how long you have to dip it before it subsides, 30 seconds or so?

[SLR No.77]

The time it takes to drop will vary from car to car, it depends how easily the oil is pushed past the oil pump due to the weight of the oil in the tank. Time it at maybe 10 second intervals and repeatedly dip the oil to work out how your own oil system behaves, you'll likely have longer than you think. Your separate dipping rod method is definitely the best way to do it.

I've found more bubbles present when using certain oils, Mobil 1 Motorsport always seemed the best at anti-frothing. You also get more bubbles if you run the system over full.

Stu.

[7 wonders of the world]

If you run a sealed system you naturally reduce the amount of air being pumped thro via the scavenge with the return oil and improve the scavenge cycle too.

[SLR No.77]

Except that the gold pump CFM is marginal as is the capacity of the belltank, running un-sealed reduces the possibility of starvation at the pressure pump. 

[duncs_c7]

Thanks for the advice guys. I run Comma Motorsport oil, for no other reason than that is what the previous owner used and he seemed to know what he was talking about!

[7 wonders of the world]

A sealed system will increase scavenge pump efficiency as it will help create a partial vacuum hence increasing the oil fill in the pump due to less dead air being present, and therefore you have less air to remove form the oil in the tower so less chance of aerated oil be pumped back into the gallery which will reduce the load the oil film can carry.