[sonofsun]

Changed oil last Sunday. Tightened the oil filter cap without a torque wrench but went by past experience. I did replace both the o-rings on the cap (the small one and the large one and also lubricated them a bit). Drove around neighborhood and to work for the past 6 days. Overall put in 130 miles with multiple trips (like 15 trips).

Then this afternoon while mowing the lawn noticed plenty of oil leak. Looked under the car and there was plenty of leak. Checked to see if leak was from drain plug. Negative.

Then opened the hood and noticed oil leak from possibly the oil housing. The O-ring gave way and bulged out a big to outside the circumference of the filter cap. Not sure if this is due to over-tightening. But hopefully lucky for me I noticed oil on my windshield in the last 1.2 miles from home and thought it was coke being spilled from the car in my front. Used windshield wipers and drove home. Then noticed that the oil was there on the road in drops.

Didn't start engine yet but did engine check and everything is ok. Also used BMW scan tool and found engine oil level to be 74mm. Not sure what the right value is. TIS doesn't have any info.

I am planning to probably replace the oil filter and o-rings with new ones. Also I added Liqui-Moly engine additive before pouring in the engine oil. I added a bit of this heavy stuff through the oil filter housing. Not sure if this caused any problems as I inspected the car atleast on 3 different days while running to see if there was any leak or any abnormal sound. It appears the engine may not have been compromised.

Planning to remove the air filter housing and such and clean all remnants of oil with de-greaser. Checked accessory belt and has no oil but will anyways clean everything to ensure belt doesn't get sucked in.

Can I just replace the filter gaskets (or possibly a new filter) and top up one quart and start the engine, idle it, check level and add more if necessary? Please help with any suggestions.

[Korz55]

You should be fine. Oil leaks always look worse than they are. Your oil level should not have gone down that far or else you would have gotten an engine light. Just replace the filter and gaskets and start it back up.

[jwalker87]

Agreed. And use a torque wrench this time! Also, there may be a 'paint mark' on the cap and housing from a previous tightening (for some reason mine has one) - lining these up is better than doing it by feel, though not as good as torquing it properly.

[sonofsun]

Thank you all. Luckily I was driving the car and not the mrs. Also I have a dashcam and went back through the video and found out where exactly the oil first started splashing onto the windshield.

May be FCPEuro sent a faulty filter gasket or something. Will get a new filter kit and couple of new quarts of oil from the dealer tomorrow when they open. Also this is a good excuse to clean up the engine bay responsibly.

[PhaseP]

The O-ring gave way and bulged out a big to outside the circumference of the filter cap. Not sure if this is due to over-tightening.

Typical common mistake of placing the big o-ring not on the correct groove. Or as you were tightening the cap, it rode up from the groove it was supposed to. Nothing to do with torque wrench usage or not.

Make sure you have the big o-ring at the correct groove and as you are tightening the filter it stays in there, some oil on the ring helps which you already did looks like. The o-ring is not supposed to be right up at he cap's lip. It is supposed to seal by pressing the side walls, it is not a flat gasket it is an o-ring.

If you search this forum or even google, you will find a lot of stories about it. Example: https://www.e90post.com/forums/showthread.php?t=1167672

Also use the MANN OEM filter, some aftermarket ones are reported to not fit well.

[Efthreeoh]

Okay, so first off, just read the oil level using the e-dipstick. And before you go topping up the oil level, read this:

https://www.e90post.com/forums/showthread.php?t=1533444

Second, you probably had the large o-ring in the wrong place and it got chewed up by the threads on the OFH and finally gave way. You can buy the o-rings separately at any BMW dealership without buying a new filter, but most auto parts stores carry the MANN HU-816x filter, which has both O-rings, so it might be easier and less expensive to just buy a new oil filter. On the next change just use the new filter and re-use the O-rings. Just as a note, I keep a few sets of the old O-rings as spares just in case something like this happens.

Now if you are going to set the torque on the cap with a torque wrench, use a beam-style wrench vs. a click type. Most 3/8ths-drive click-type torque wrenches are not accurate at 18 pound-foot, which is the cap torque setting. Beam-style torque wrenches are very accurate at low torque values. But really, just tighten the cap till it stops turning, it's tight at that point.

And the paint mark has noting to do with torque setting. The paint mark is simply a quality control (QC) mark put on at the factory when the engine is built as an inspection mark that verifies the cap has been correctly assembled by the assembler.

[sonofsun]

thank you all. replaced the o-ring. Not sure how it made it up to the top. I may've mistakenly placed it on the top groove even though I've changed the oil many times before.

While cleaning up the underside I did find a hole in the oil pan that I've posted about in a separate thread.