Something not to do (during an oil change)

[JimD]

My 2009 e88 (n52) is out of warranty so I change the oil myself. I use 5 qt jugs from Walmart and Mann 816X oil filters from Amazon. I changed it yesterday and today I had a mess. I tightened the oil filter housing cap like it was a piece of plastic. I have written down that it gets 25 Nm (18.44 ft lbs) but I didn't look, just snugged it up. My wife and I went to church which is, unfortunately, about 15 miles away. No problem getting there but when we got in to go to a restaurant to meet my son, the silly oil level alarm said I needed to add oil. We were only going a couple miles so I lifted the hood and saw oil all over the engine coming out from under the oil filter housing cap. I went in to have lunch and got a paper towel in the restroom. I removed the cap with my hand - bad sign - and reseated the O-ring. Then I tightened by hand and dumped in the quart I keep in the trunk. I was still getting the oil level alarm so I stopped and got another 5 quart on the way home. I put in another quart and drove the rest of the way home. So when I get home I find the O-ring bulging again and evidence of more oil loss. ( when I stopped at Walmart it didn't seem to be leaking)

Brain finally starts working and I check the torque requirement. Dig out the 3/8 torque wrench and check it. Nowhere near tight enough. After it is torqued up (3 times) I try and remove it by hand. No way. Bottom line is I ran my engine low on oil because I was stupid. I dumped in a quart and a half and will check it shortly. All because I didn't torque it, or at least check the torque spec, the first time.

I could blame BMW for putting silly metric specs on the filter cap or for not giving me a real dipstick so I could see what was going on but the bottom line is I caused my own problem. BMWs quirkiness didn't help but they didn't cause the problem either.

So if you change your own oil, remember the drain plug and the oil filter cap get tightened to the same level and a torque wrench isn't a bad idea. Mine is from HF and cost about $10. It is, undoubtedly, not terribly accurate. But it is good enough for oil changes, at least at my house. 18.44 ft lbs is a pretty good pull on a 3/8 ratchet for me. Not everything I can do but more than just snugging.

[awns729]

Sorry to hear that. Probably didn't cause significant damage. I once ran my subaru 1.5-2 quarts low once by accident. Capacity on that car is only 4.5 quarts! I didn't specifically tell Blackstone on the next UOA, but the wear numbers suggested that I did a few autocross events and nothing more. Your car was only low for a short distance, so this will mostly serve as a reminder for all of us to check our work but hopefully 0 damage to your 1er.

[awns729]

FWIW - 18 ft-lbs is roughly the weight of 2 bowling bowls hanging from a 1 foot wrench if that helps anyone calibrate the amount of force to tighten the filter with. I used an adjustable wrench on the oil filter cap wrench and made it pretty snuck. Next time I'll torque it right!

[Iron Man]

Originally Posted by JimD

My 2009 e88 (n52) is out of warranty so I change the oil myself. I use 5 qt jugs from Walmart and Mann 816X oil filters from Amazon. I changed it yesterday and today I had a mess. I tightened the oil filter housing cap like it was a piece of plastic. I have written down that it gets 25 Nm (18.44 ft lbs) but I didn't look, just snugged it up. My wife and I went to church which is, unfortunately, about 15 miles away. No problem getting there but when we got in to go to a restaurant to meet my son, the silly oil level alarm said I needed to add oil. We were only going a couple miles so I lifted the hood and saw oil all over the engine coming out from under the oil filter housing cap. I went in to have lunch and got a paper towel in the restroom. I removed the cap with my hand - bad sign - and reseated the O-ring. Then I tightened by hand and dumped in the quart I keep in the trunk. I was still getting the oil level alarm so I stopped and got another 5 quart on the way home. I put in another quart and drove the rest of the way home. So when I get home I find the O-ring bulging again and evidence of more oil loss. ( when I stopped at Walmart it didn't seem to be leaking)

Brain finally starts working and I check the torque requirement. Dig out the 3/8 torque wrench and check it. Nowhere near tight enough. After it is torqued up (3 times) I try and remove it by hand. No way. Bottom line is I ran my engine low on oil because I was stupid. I dumped in a quart and a half and will check it shortly. All because I didn't torque it, or at least check the torque spec, the first time.

I could blame BMW for putting silly metric specs on the filter cap or for not giving me a real dipstick so I could see what was going on but the bottom line is I caused my own problem. BMWs quirkiness didn't help but they didn't cause the problem either.

So if you change your own oil, remember the drain plug and the oil filter cap get tightened to the same level and a torque wrench isn't a bad idea. Mine is from HF and cost about $10. It is, undoubtedly, not terribly accurate. But it is good enough for oil changes, at least at my house. 18.44 ft lbs is a pretty good pull on a 3/8 ratchet for me. Not everything I can do but more than just snugging.

Hopefully no serious damage was done to your engine.

One other thing that should always be done is to replace the gaskets as well. The BMW dealer I went to did not replace my gaskets and my oil cap started seeping oil.

While it is nice to have a topside oil filter change, the set up can be pretty sensitive. I imagine the N52 must run with a pretty decent oil pressure level for the oil filter to leak so easily.

[JimD]

I was surprised by the apparent oil pressure too. It squirted over most of the drivers side of the engine compartment. I put cardboard under it when I got home but it still left a couple oil stains on the driveway. The second one happened when I backed up to clean up the first one. Changing the angle made more run off. This appears to be the magnitude of the "damage" - a messy engine compartment.

The BMW "add one quart" message was not very helpful when I needed to know what I had lost. When I got home, it was more than a quart so I had to add, then drive, then add again. My mistake, but the car's system didn't help fixing it. At least I know the car's measurement system works. But it is still not a system I like. It has a scale on the display but I am pretty sure it is meaningless. All it is set up to do is tell you if you are a quart or more low or above full. If you are less than a quart low, it shows you as full. It won't display a pint low, in other words. It also won't apparently display 2 quarts low. Not a very good system. Totally tuned to displaying the "add a quart" message. In no way a digital equivalent of a dipstick.

[bmw1racer]

Originally Posted by JimD

The BMW "add one quart" message was not very helpful when I needed to know what I had lost. When I got home, it was more than a quart so I had to add, then drive, then add again. My mistake, but the car's system didn't help fixing it. At least I know the car's measurement system works. But it is still not a system I like. It has a scale on the display but I am pretty sure it is meaningless. All it is set up to do is tell you if you are a quart or more low or above full. If you are less than a quart low, it shows you as full. It won't display a pint low, in other words. It also won't apparently display 2 quarts low. Not a very good system. Totally tuned to displaying the "add a quart" message. In no way a digital equivalent of a dipstick.

All that tech to measure the oil level and it doesn't appear to even work correctly... How ridiculous.

[Iron Man]

Originally Posted by JimD

I was surprised by the apparent oil pressure too. It squirted over most of the drivers side of the engine compartment. I put cardboard under it when I got home but it still left a couple oil stains on the driveway. The second one happened when I backed up to clean up the first one. Changing the angle made more run off. This appears to be the magnitude of the "damage" - a messy engine compartment.

The BMW "add one quart" message was not very helpful when I needed to know what I had lost. When I got home, it was more than a quart so I had to add, then drive, then add again. My mistake, but the car's system didn't help fixing it. At least I know the car's measurement system works. But it is still not a system I like. It has a scale on the display but I am pretty sure it is meaningless. All it is set up to do is tell you if you are a quart or more low or above full. If you are less than a quart low, it shows you as full. It won't display a pint low, in other words. It also won't apparently display 2 quarts low. Not a very good system. Totally tuned to displaying the "add a quart" message. In no way a digital equivalent of a dipstick.

Well, a dipstick may not necessarily tell you how low on oil you may be either.

Once the level is low enough that it does not register on the dipstick, you would be guessing on how much to add. How much oil it takes to not register I'm sure varies by make/model and oil sump size.

But don't get me wrong, I am definitely "pro" dipstick and wish our vehicles had one.

[Dackelone]

Sorry to hear about this JimD Its always a good idea to do a visual check for those green dots on the oil filter cap. They should always NOT be lined up, but apart some. The factory puts a green mark on the oil filter cap, so BMW knows the oil filter gets changed down the (service)road.

When the oil filter cap is retorqued... the green dots will be apart.





green dots are apart...

[JimD]

My dots weren't lined up originally nor are they now. That is a mistake I am capable of making but not the one I made. There is a limit to what a dipstick says but it isn't one quart. It will show you that you are more than a quart low, most cars would be a couple quarts low if you were off the stick. And you could dump a quart in and see if you were on the stick. If not, you dump another and check. No need to start the car and run it a few miles. You fill it up and know you are full without driving the car. Much better.

[NorthernDancer]

My 2 green dots are very closely aligned and I've done 3 oil changes myself. Once I noted in my records that my oil filter cap was very loose (essentially 0 ft pds, last change at Florida dealer) but no oil leakage whatsoever. I also think its possible to put the large oil cap O ring in the wrong groove.

[Freon]

I wouldn't be surprised if people have put the o-ring on the threads.

[JimD]

I checked to see if the o-ring was in the groove but that wasn't my problem either. I'm not sure it is the torque that the cap needs but when I torque to ~18 ft. lbs, it buries about half the o-ring into the aluminum casting. If I just tighten to "snug" the O-ring is above the casting and when the oil pressure hits it, it bulges out (and leaks). The O-ring being down into the casting is probably the key point, the torque to get it there may not matter much if at all.

Plastic is also pretty bad about creeping under load. Even if you torque to 18 ft. lbs at the oil change, that torque may be relieved with creep in the plastic while the motor is operating. If my theory is right and the O-ring being down into the cast some is the key, it wouldn't matter what the torque remaining is.

[bmw1racer]

Originally Posted by JimD

Plastic is also pretty bad about creeping under load. Even if you torque to 18 ft. lbs at the oil change, that torque may be relieved with creep in the plastic while the motor is operating. If my theory is right and the O-ring being down into the cast some is the key, it wouldn't matter what the torque remaining is.

Not sure about other models, but my E36 had an aluminum oil filter cap that was held down with a long bolt... Not going to be much creep there.

I know the use of plastics is to save weight and cost, but you've gotta wonder how reliable they are, especially in the hot engine compartment.

[MightyMouseTech]

The o-ring MUST be inside the housing. They don't work very well when outside what they are sealing.

Put a bit of fresh oil on the o-ring and it will slide in a lot easier.

[JimD]

There are several pictures in this thread I wrote a long time ago:

http://www.1addicts.com/forums/showthread.php?t=301440

I clearly knew what to do and had done it right several times but then I messed up. I think part of the reason might be that I change more cars with metal can type filters than I do cars with a loose filter element. For the metal can type, you only get it basically hand tight. Put it on with 18 ft lbs and you may leave the filter gasket behind when you remove it. You might even break a wrench removing it. I usually use a wrench but I don't put much pressure on it. So when I did my bimmer, I didn't think about what I was doing and did what I usually do. And it was the wrong thing to do.