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Rest in peace, Coach
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Kinda/sorta...

When you remove the oil filter, it releases a seal between the oil filter canister and the tube running down to the drain pan, and all the oil inside the filter canister will escape down the drain pan. So basically, remove the filter, make sure you either siphon out a half a quart of oil if your dipstick is at max, or be prepared for a messy garage floor because you'll need to dump in about half a quart of oil in the oil filter canister before you re-install the filter, otherwise next time you start your engine, it'll be like a dry start.

And if you overfill your drain pan, the release valve will leak out the excess oil and you'll have a messy garage floor.
 

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Sorry to be obtuse but I plan on doing the 7.5k intermediate oil change on my '03 330Ci after it arrives, and am unclear about the oil filter release valve that returns the oil to the pan.

If this is the case, if the oil filter is changed after the old oil is drained from the pan and the drain plug reinserted, isn't old oil from the filter 'cup' being returned to the oil pan? If the oil drain plug isn't removed a second time to remove this old oil, doesn't the old oil from the filter cup get mixed with the new oil that is subsequently added? The amount of oil in the cup isn't likely that great, still, it is old oil.

Wouldn't it make more sense to change the oil filter before the pan is drained of old oil to actually get all of the old oil, both the old oil that is in the drain pan and the old oil that is in the filter cup?

The only problem I could see with changing the oil filter before draining the pan is that the extra oil in the pan might force a seal to leak, but I wouldn't think it likely since the engine won't be started between the time the oil filter is changed and the oil pan drained.

Sorry if this has been addressed before, I just want to make sure I understand the proper procedure before I attempt it.
 

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Rest in peace, Coach
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ruteger said:
Sorry to be obtuse but I plan on doing the 7.5k intermediate oil change on my '03 330Ci after it arrives, and am unclear about the oil filter release valve that returns the oil to the pan.

If this is the case, if the oil filter is changed after the old oil is drained from the pan and the drain plug reinserted, isn't old oil from the filter 'cup' being returned to the oil pan? If the oil drain plug isn't removed a second time to remove this old oil, doesn't the old oil from the filter cup get mixed with the new oil that is subsequently added? The amount of oil in the cup isn't likely that great, still, it is old oil.


Yes. That is why in most DIY manuals and postings, they suggest you remove the oil filter as the first step in changing the oil.

Wouldn't it make more sense to change the oil filter before the pan is drained of old oil to actually get all of the old oil, both the old oil that is in the drain pan and the old oil that is in the filter cup?

The only problem I could see with changing the oil filter before draining the pan is that the extra oil in the pan might force a seal to leak, but I wouldn't think it likely since the engine won't be started between the time the oil filter is changed and the oil pan drained.

Sorry if this has been addressed before, I just want to make sure I understand the proper procedure before I attempt it.
The oil drain pan accomodates ~7 quarts of oil. When the dipstick reaches MAX it's actually reading about 6 quarts of oil. According to my personal experience and the Bentley's manual, the oil drain pan on the E46es has a pressure release valve, so when the drain pan is overfilled it will slowly leak out the excess oil, thus preventing damage to your engine.
 

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Thanks. The owner's circle online owner's manual has no oil change instructions (that I could find), and the oil change DIY over at bmw330ci.com misses this small, but important, nuance.

The bmw330ci.com DIY has the change sequence being completely straightforward (drain oil from pan, replace drain plug, change filter, add new oil) with no mention of the oil filter return valve. However, the narrator does mention that he couldn't get anywhere near the 6.9 quarts of new oil in, something like only 5.5 quarts.

I may be interpreting your information incorrectly, but are you saying it is only possible to add 6 quarts, even though the manuals say the capacity is nearly 7 quarts?

This would actually make sense if the narrator of the DIY was retaining the old oil from the oil filter cup in the pan. The amount in the cup would come close to making up the difference between 6 quarts and the 5.5 quarts that he was actually able to add.

I vaguely remember reading somewhere that this particular oil change DIY was incorrect, but since it was sometime ago, I don't recall it being specific about what information was wrong with the DIY.
 

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oil change

If I'm reading these posts right you should put 1/2 quart of oil in the new filter every time you change it to avoid a dry start. Is that correct?????????
thanks
vern
 

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Rest in peace, Coach
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ruteger said:
Thanks. The owner's circle online owner's manual has no oil change instructions (that I could find), and the oil change DIY over at bmw330ci.com misses this small, but important, nuance.

The bmw330ci.com DIY has the change sequence being completely straightforward (drain oil from pan, replace drain plug, change filter, add new oil) with no mention of the oil filter return valve. However, the narrator does mention that he couldn't get anywhere near the 6.9 quarts of new oil in, something like only 5.5 quarts.

I may be interpreting your information incorrectly, but are you saying it is only possible to add 6 quarts, even though the manuals say the capacity is nearly 7 quarts?

This would actually make sense if the narrator of the DIY was retaining the old oil from the oil filter cup in the pan. The amount in the cup would come close to making up the difference between 6 quarts and the 5.5 quarts that he was actually able to add.

I vaguely remember reading somewhere that this particular oil change DIY was incorrect, but since it was sometime ago, I don't recall it being specific about what information was wrong with the DIY.
The actual capacity is 6.7 quarts. My speculation is that the MAX line on the dipstick indicates 6 quarts of oil, and the MIN line indicates 5 quarts. Anything over 7 quarts will leak out via the release valve, as my first DIY oilchange indicated. I drained and put in 7 full quarts of oil, and saw a small puddle of oil underneath my car the next morning.

And your speculation would be correct, if you don't change the oil filter first, you will only get about 5.5 quarts out, since the oil filter canister holds about .5 quart.
 

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I didnt know that oil will slowly drain via a pressure relief valve. That is good information. Especially if you *think* you may have an oil leak. I learn something new every day.
 

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hockey-holic
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Sorry....

I'm a bit thick this morning after reading this thread a few times. :banghead:

Hack's experience recommendeds that the oil filter be removed before (?) removing the drain plug after taking about a half a quart out to prevent spillage. I'd rather not take the chance of opening the filter housing and oozing oil all over the place. Plus, I don't have any way to pull the oil out other than the plug.

Couldn't you just pull the plug and grab the oil filter after a few seconds of draining or even before you put the drain plug back in? Won't that allow for the oil in the tube to drain down to the drain pan and out getting your 6 qts of oil out?

Thanks for the info on putting a bit of oil in the filter housing to help reduce a dry start. That's new to me.

Bob
 

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Wishes he had an XBoX
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whoa, this is getting a little more complicated than i thought...

ive changed oil several times now, and i've always put in anywhere from 6.5 to nearly 7 quarts of oil regardless of what i changed first; oil filter or drain old oil. can someone just put toget a quick list on what to do first as i understand it now as:

change filter
drain oil

but of course this would only make sense on bimmers right? because i know that oil filters on other cars(japanese) the filters are screwed on their side, so if you were to remove it before draining oil, you'd have more of a mess that you'd expect, right??
 

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Rest in peace, Coach
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Re: Sorry....

exBMWannabe said:
I'm a bit thick this morning after reading this thread a few times. :banghead:

Hack's experience recommendeds that the oil filter be removed before (?) removing the drain plug after taking about a half a quart out to prevent spillage. I'd rather not take the chance of opening the filter housing and oozing oil all over the place. Plus, I don't have any way to pull the oil out other than the plug.

Couldn't you just pull the plug and grab the oil filter after a few seconds of draining or even before you put the drain plug back in? Won't that allow for the oil in the tube to drain down to the drain pan and out getting your 6 qts of oil out?

Thanks for the info on putting a bit of oil in the filter housing to help reduce a dry start. That's new to me.

Bob
No oil will ooze out when you remove the filter housing. However, you should have something to catch the oil filter right away, since the oil filter will trap SOME oil. As soon as you unscrew the oil filter housing, a seal between the oil filter and the tube between the housing and the drain pan releases and the remaining oil in the oil filter housing drains into the drain pan. Then you can remove the drain pan plug and extract most of your oil.

Basically, here are the steps that I follow:

1) Warm up engine to operating temp
2) Wait 10-15 minutes for engine to cool down slightly
3) Pop hood, remove engine cover cap
4) Remove oil filter housing
5) Remove drain plug and extract oil
6) When oil drains at a slow drip, re-insert oil drain plug
7) Add half quart of oil in filter housing, re-install filter
8) Pour the remaining half quart of oil in through the engine cover cap, pour 5 additional quarts in
9) Screw on engine cover cap, start engine, idle until operating temperature
10) Check dipstick level and add oil to MAX level on dipstick if necessary.
 

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King of Rear Clunks
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Dan, you're making this WAY more complicated than it needs to be. :tsk: :tsk:
 

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Rest in peace, Coach
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Kaz said:
Dan, you're making this WAY more complicated than it needs to be. :tsk: :tsk:
:dunno: Just pointing out my steps. It just SOUNDS complicated since I listed almost every single step. Most of the time I just keep a couple of things in mind:

a)Add 1/2 quart in filter housing
b)put oil on the seals before installing

That's pretty much it.
 

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2001 M3:Stick, what else?
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Discussion Starter · #16 · (Edited)
Man... this is sounding complicated. I've never added any oil to the oil filter housing.

I just extract out the oil (6 quarts come out), replace the filter and add new oil--- as per the DIY on bmw330ci.com.

Am I causing wear by not adding oil to the filter housing??

If you pour oil into the filter housing... doesn't it just drain into the engine right away?
 

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6) When oil drains at a slow drip, re-insert oil drain plug
7) Add half quart of oil in filter housing, re-install filter
If "When you remove the oil filter, it releases a seal between the oil filter canister and the tube running down to the drain pan, and all the oil inside the filter canister will escape down the drain pan", wouldn't filling the cup with new oil before installation of a new filter do the same thing? Unless I'm missing something, it sounded like it was the canister itself that prevented the old oil from draining from the cup into the pan.

It would seem that filling the cup with new oil when there wasn't an oil filter canister present would allow the new oil to just flow straight into the sump. The cup would still be empty when the new canister was installed because the canister is what was preventing any oil in the cup from draining to the sump.

I guess I just want to know what is preventing the new oil from draining back into the sump when there is no oil filter canister present to stop it.

As for the previous posting to bmw330ci.com for the DIY oil change link, that's exactly the place that is causing much of the confusion. There is no mention whatsoever in the DIY about the oil from the cup returning to the oil pan.

Again, I apologize if I'm being extremely dense about how this is done. It just seems like there is some conflicting info and I'd like to be able to do the task at 7,500 miles properly the first time.

I hope I'm not too stupid to drive a 330Ci...:eeps:
 

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hockey-holic
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Rutger, good point. With the filter housing off, you don't have the pressure to keep the oil in the "tube".....unless the drain plug and engine oil cap are closed and it is air tight. Then maybe the oil (due to air pressure) will stay in the tube. But gravity would probably take over and drop the oil down replacing the air in the drain pan.:dunno:

BTW, on my first DIY oil change, I only got about 5 qts out. I attributed that to putting the front end on ramps and not getting all of the oil out of the drain pan due to the angle.

Bob
 

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Rest in peace, Coach
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Next time you do a DIY oil change, try pouring a half quart of oil down the canister (the outside half, not straight down the middle tube) first and then screw in th filter. The oil doesn't drain immediately.

And observe the first time you fire up the engine and see if there's any difference between how you normally change oil and the method of adding oil in the canister before hand, see how much smoother the first time you fire up the engine after an oil change is when you DO add oil in the canister.

I'm not sure if there's long term problems with dry-starting your car, since synthetic oil is suppose to cling to engine parts and still provide minimum lubrication even when engine is dry. I figure the extra step in the oil change will put my mind at ease.
 

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2001 M3:Stick, what else?
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Discussion Starter · #20 ·
Dan---

Since I've been dry starting my car anyway for the last couple of years, 1 more wont kill it.

In that case, can I just do as filter swap without worrying about the oil overflowing... correct??
 
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