N52 oil change capacity without filter change

[Liam22]

I don't suppose there's information about oil change volume *without* changing the filter?

I tend to do an annual oil filter change on a race car, with new oil every 3 races.

The lack of dipstick is killing me! And my dash oil level indicator doesn't work. The sensor itself is fine, but since I deleted the heater water circuit, the car refuses to show a level.

I can get an oil level reading with the engine running using the C310 scan tool. But it's in mm, so I don't know what min and max look like. I've been trying to collect mm data at 60º water temp, 40º oil temp, but I'm not sure it's reliable.

[1536Z4]

Found this on an American site .

Oil Filter Change Can Affect the Amount of Oil Needed for Your Car
An oil change almost always goes hand-in-hand with an oil filter change. This is to make sure that no debris and other contaminants will be present in the new lubricant. Replacing the oil filter also has an effect on the final amount of motor oil needed for the engine.

For example, a V6 engine may require about 3 and 7/8 quarts of motor oil if you do not replace the oil filter. If you also change the oil filter, you will need about 4 and ¼ quarts of oil.

The difference accounts for the oil that is present inside the oil filter. This is equivalent to about 3/8 quarts. If you do not replace the oil filter, then you risk contaminating the new (3-7/8 quarts) oil with the old (3/8 quarts) oil.

Obviously it depends on the size of filter but gives you an idea .

[Liam22]

1536Z4, thanks. Quarts, eh? Gotta love it...

I can't see the oil filter holding more than ~200ml of oil. A cartridge type (as we have) is going to hold a lot less than a spin-off filter.

It's just annoying not to have an accurate way of measuring oil level. Especially as I think my engine consumes oil, so I can't just measure what gets drained and refill with the same amount.

[enuff_zed]

1536Z4, thanks. Quarts, eh? Gotta love it...

I can't see the oil filter holding more than ~200ml of oil. A cartridge type (as we have) is going to hold a lot less than a spin-off filter.

It's just annoying not to have an accurate way of measuring oil level. Especially as I think my engine consumes oil, so I can't just measure what gets drained and refill with the same amount.

Admittedly I'm just brainstorming here but.............
The filter sits at the top of the engine, so how much effect does gravity have? Is there a non-return or pressure valve to stop it draining down?
Is this why you have to check them warmed up with the engine running, so the filter is full?
Just wondering whether you could completely drain and refill as per the book figures. Then run it just until it's warmed up properly, leave it to cool, whip out the filter and see how much is in it?

Or maybe......
Fill it with the book figure and immediately see how many mm the scanner says.
Then drain out 1 litre (as I believe that is the allowable amount between max and min) and check the mm again.

[Liam22]

As far as I can make out, the reason for oil level check with engine running is because the oil level sensor (in the sump) becomes fully submerged at about 5l. The oil needs to be circulating so that the sump level falls below the sensor height.

I've watched the sensor value as I've filled the engine from cold/empty.

I always drain with the oil filler cap open, in case of air lock.

Next time I'll also crack the filter cap open to see if that releases any more oil. But at this point I'd may as well spend the extra £5+5 mins to replace the filter, too. There's just not much point replacing the filter every 300-500 miles!

[1536Z4]

There's just not much point replacing the filter every 300-500 miles!

If it was me for the price of a new filter I would be replacing the filter every time and opening up the old one to see if any nasty bits were hanging around but I am a bit weird like that

[enuff_zed]

As far as I can make out, the reason for oil level check with engine running is because the oil level sensor (in the sump) becomes fully submerged at about 5l. The oil needs to be circulating so that the sump level falls below the sensor height.

I've watched the sensor value as I've filled the engine from cold/empty.

I always drain with the oil filler cap open, in case of air lock.

Next time I'll also crack the filter cap open to see if that releases any more oil. But at this point I'd may as well spend the extra £5+5 mins to replace the filter, too. There's just not much point replacing the filter every 300-500 miles!

Time to talk nicely to 'Oilman' about a bit of sponsorship from Opie Oils

[Liam22]

Time to talk nicely to 'Oilman'

LOL! He already does very nicely out of me from my Millers Nanotech CFS habit

[Scooba_Steve]

At one point I was getting MANN filters for about £6 delivered from Amazon, keep an eye out and buy 100!

I've never squeezed out a saturated filter, but can't imagine there is more than 50/100 ml lurking in that and the oil cooler.