[Greg220]

I'm preparing to do an oil change by myself for the first time (on 2006 330i sedan). I read a lot of posts and watched videos but the thing that worries me most is opening the drain plug while I'm under the car. So, I have two questions:

1) which direction and how far in that direction will the oil flow immediately after removing the plug? I'd like to make the oil doesn't spill on me or on the floor.
2) would it make sense to remove the drain plug first before opening the engine oil cap, so that the flow starts slower and doesn't splash on my hands?

[kkasson]

Be sure the car is safely supported first of all. Either on ramps, or securely on jack stands. Way more important than getting oil on yourself.

But as for the question, depending on how high it is, I'd guess it will reach 9 inches or so from the drain plug. I find the best way to do it is to loosen the plug and begin to unscrew it by hand, but keep pressing it towards the oil pan as you do so. You'll feel when it comes all the way loose, and if you press it back it will mostly hold the oil in. Then when you feel it's all the way out, just quickly pull the plug and your hand away. If you're wearing gloves then it shouldn't be a problem at all.

Get a roll of blue shop towels and put a few around the drain pan just to catch anything that might spill, but it will come pretty much straight out of the drain hole.

You might make more of a mess with the filter...you'll want to unscrew it really slowly or oil will spill out. You could put a few of the towels around the housing to try to catch that in case any spills.

[Greg220]

Thank you for great tips! The car will be on 7" ramps, so I think the distance from the drain plug to the floor will be around 10". So, should I expect the flow to go directly downwards? And do you think I could slow down the initial drain flow if I don't open the engine oil cap first?

[kkasson]

It comes out in a roughly parabolic path. These pictures aren't mine but they show about what it will look like. It will extend away from the drain plug roughly 9 or 10 inches, I'd guess.

I'd say to just remove the cap before you start. If you leave the cap on, the flow tends to kind of start and stop as the vacuum comes and goes. The oil will drain faster with the cap removed, but it will also be a steadier stream which will be easier to deal with.

[Efthreeoh]

I always recommend working underneath a car that is on 4 jackstands with the wheels off the ground, so the car can't roll. You'll never find me under a car on ramps. That said, the N52 330i for the manual trans drivetrain has the oil drain on the bottom of the pan (vs. the side), when the car is level (i.e. on 4 stands ) the oil drains straight down. If the car is an automatic the oil pan may have the drain on the side, I'm not sure; both of my N52s are manuals. Just get a big oil drain pan; Advanced Auto sells huge yellow ones, so there is no guess work.

The correct procedure is to first loosen the oil filter cap all the way to let air into the engine while the oil drains out, then open the drain bolt.

[Three_thirty_I]

Originally Posted by Efthreeoh

I always recommend working underneath a car that is on 4 jackstands with the wheels off the ground, so the car can't roll. You'll never find me under a car on ramps. That said, the N52 330i for the manual trans drivetrain has the oil drain on the bottom of the pan (vs. the side), when the car is level (i.e. on 4 stands ) the oil drains straight down. If the car is an automatic the oil pan may have the drain on the side, I'm not sure; both of my N52s are manuals. Just get a big oil drain pan; Advanced Auto sells huge yellow ones, so there is no guess work.

The correct procedure is to first loosen the oil filter cap all the way to let air into the engine while the oil drains out, then open the drain bolt.

Ah, that explains something that kinda bothered me for a while - mine being a manual has the sump plug as you say, on the bottom of the oil pan, not on the side. So in this case, just straight down and easy.

With the E46 M54 which has it on the side, I just position the mouth of the oil container so that the edge closest almost directly below the drain plug to start with, and then as the oil starts to drain I just move it back a bit, because at some point the flow will tend to change direction. But I always put down some old newspaper under everything just in case some oil doesn't make it into the container.