[sree]

Hi all,

I am a new owner of a gorgeous 2015 M235i (38.400miles) and have a question about an oil leak

I cold started my car this AM after a few days in transit (shipped the car from San Francisco to Maryland) and noticed a burnt oil smell in the cabin. I only smelled this while idling, and for about 20ish miles of driving which dried up soon after.

I noticed a few drops of oil (still wet) on the accessory belt tensioner (see attached photo) and it's just about hitting the serpentine belt. My local indie shop found a few drops of oil in the underbody also, possibly dripping all the way down.

They suspect it's an oil pan gasket issue and are quoting around ~1300 (conservative estimate for 7 hours of labor) to replace. The price makes sense for the oil pan gasket replacement, but I am confused about the source of the issue. Isn't the belt tension located above the oil pan? and this should indicate a leak higher up by the oil filter housing gasket?

Thanks in advance,
Sree

[pikcachu]

most likely is the oil filter housing gasket cause it's right above the belt....

I would be worried if they said is the oil pan gasket cause seems to me they are trying to screw you.... changing the pan gasket and the leak is still there...

maybe is also leaking from the pan but oil from the belt is not coming from the pan

[Pussiwillow]

Oil filter housing gasket
Drive with caution; it can cause the belt to slip off and get sucked in by the crank pulley, pulling it into and often past the front main seal; which puts belt shards into the oil pan and clog the pick up tube, starving the rod bearings and other bearings, but rods will be the first to show it.
Avoid driving it much til it's fixed

This is very common.
You'll need the oil filter housing gasket, you'll need the oil cooler gasket and the 2 little o rings for the cooler lines, I recommend replacing the bolts as well, I always order everything from FCP euro and I believe they have a package put together for this. If you need help locating what you need pm me

[Pussiwillow]

BMW Oil Cooler Line O-Ring - Genuine BMW # 17222245358 (2)


BMW Engine Oil Filter Housing Gasket - Elring # 11428637821 (1)

BMW Oil Cooler Seal - Elring # 11428637820 (1)

I reused my bolts but some recommend replacing them with new

These are the items I ordered when doing it

You'll want to change your oil after
VERY IMPORTANT
follow bmw procedure to priming the oil pump after doing so, people had rod bearing issues and bmw updated the procedure with priming the oil pump

[Rich.Wolfson]

Originally Posted by Pussiwillow

Oil filter housing gasket
Drive with caution; it can cause the belt to slip off and get sucked in by the crank pulley, pulling it into and often past the front main seal; which puts belt shards into the oil pan and clog the pick up tube, starving the rod bearings and other bearings, but rods will be the first to show it.
Avoid driving it much til it's fixed

This is very common.
You'll need the oil filter housing gasket, you'll need the oil cooler gasket and the 2 little o rings for the cooler lines, I recommend replacing the bolts as well, I always order everything from FCP euro and I believe they have a package put together for this. If you need help locating what you need pm me

I agree with all this but my 2014 M235i doesn't have the o-rings. I will be doing that job prophylactically over the weekend BTW at 75,000 miles. There are good videos from FCP and Youtube.

And those bolts are one time use, 3 of them, and cheap so no reason to not replace them. They stretch when torqued because they are aluminum.

///Rich

And yes, get it fixed as quickly and you should find another shop. That is something they should have well been familiar with.

[XutvJet]

Do not, I repeat DO NOT drive the car until you replace the belt and throughly clean ALL the oil from the pulley system and surrounding area. With oil on the belt, the motor runs a big risk of the belt slipping off the pulleys and getting lodged behind the crank pulley, crashing through the oil seal and getting sucked into the oil pan. Not joking here.

The source of the leak is either an improperly sealed oil filter or a leaking oil filter housing gasket.

[Ajowhan]

Sorry this happened to you.

[sree]

Thank you all! I'm thinking I totally misheard the shop about the oil pan vs. oil housing. I am definitely taking the car in to get the job done professionally (I don't have the tools or space to do it myself.)

[sree]

Originally Posted by pikcachu

most likely is the oil filter housing gasket cause it's right above the belt....

I would be worried if they said is the oil pan gasket cause seems to me they are trying to screw you.... changing the pan gasket and the leak is still there...

maybe is also leaking from the pan but oil from the belt is not coming from the pan

Pretty sure I saw some grease by the oil filter housing. Will confirm with the shop again.

[sree]

Originally Posted by Pussiwillow

VERY IMPORTANT
follow bmw procedure to priming the oil pump after doing so, people had rod bearing issues and bmw updated the procedure with priming the oil pump

Can you point me to more reading on this? Couldn't find anything BMW-related :

[XutvJet]

Originally Posted by sree

Can you point me to more reading on this? Couldn't find anything BMW-related :

This is one the few jobs I'd rather have BMW do. You'll know they'll follow the procedures and put the risk on them if something goes wrong. It might cost 20%-30% more, but in this instance, it's worth it, IMO.

[sree]

Originally Posted by XutvJet

Do not, I repeat DO NOT drive the car until you replace the belt and throughly clean ALL the oil from the pulley system and surrounding area. With oil on the belt, the motor runs a big risk of the belt slipping off the pulleys and getting lodged behind the crank pulley, crashing through the oil seal and getting sucked into the oil pan. Not joking here.

Agreed - no driving the car until this is fixed.

[sree]

The car's back at my old favorite / trusted indie. Turns out the oil filter housing gasket was leaking indeed and there was also a small leak with the oil level sensor by the oil pan. Smaller job than the entire oil pan gasket repair for now. Will find out more if any of the belts/pulleys need to be replaced.

[Rich.Wolfson]

Originally Posted by sree

The car's back at my old favorite / trusted indie. Turns out the oil filter housing gasket was leaking indeed and there was also a small leak with the oil level sensor by the oil pan. Smaller job than the entire oil pan gasket repair for now. Will find out more if any of the belts/pulleys need to be replaced.

I did that job this week and changed the tensioner and belt too just because. Oil on that belt is simply not a good thing.

///Rich

[sree]

Originally Posted by Rich.Wolfson

I did that job this week and changed the tensioner and belt too just because. Oil on that belt is simply not a good thing.

///Rich

Heard back from the shop, oil leaked down the front but nothing on the belt or pulleys. All good and he dis not recommend replacing them. Picking the car back up to confirm everything is solid.