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I changed the oil yesterday and have done this a number of times. I dropped the oil filter and lubed the new oil filter and replaced O ring for 3 screw torx head cover and tighten to specs. When I went outside I found oil coming from 3 torx screw cover for oil filter, about the size of 2 half dollars on the floor.
I cleaned the bottom off and about 3 hrs later had a small oil leak about the size of a quarter on the floor.

When replacing cover does anyone think I could of pinched this O ring or any other thoughts of oil leak. I am using Amsoil 20w 50 I was thinking about dropping all of the oil and replacing O ring and refilling with the same clean oil using a clean pan.

Thanks

Kevin
Alton IL
 

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Oil Change Leak

You will need to drain the oil and drop the cover. Be sure the old seal came out with the old filter. If it stayed on the engine, the filter may sit so low that it holds the cover slightly open. Be sure the groove for the o-ring is clean. Also be sure the mating surface of the cover is flat. It would not be to hard to bend the ears. I use brake cleaner to clean the cover and bottom of the oil pan. All the parts should be clean and dry when you re-assemble.


Chuck Swenson
 

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O ring

Just about the only explanation unless you got some debris between the two.
I'd just drain into a clean pan and reuse the oil as well...

Good Luck

Spence
 

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mhmorg said:
When replacing cover does anyone think I could of pinched this O ring or any other thoughts of oil leak.
The o-ring being out of its groove is exactly what I'm thinking. Before you drain the oil and remove the cover, though, pick up a new o-ring -- the old one very likely won't be reusable.

Oh, and when you put it all back together, resist the temptation to really cinch down the three Allen bolts (you'll want to, to "make sure" it doesn't leak again!). The reason is that excessive tightening does *nothing* to increase the seal preload. The cover is arranged such that once the cover plate seats against the crankcase, the cover can't go any farther -- period. *All* the sealing is performed by the o-ring, which is slightly compressed in its groove (and in fact the depth of the groove determines how much the o-ring is compressed, so it can't be *over* compressed. All you'll do by cinching it down harder is snap off the bolt heads.

HTH,
 

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One more hint. Lightly lubracate the O-ring with oil before you put it on the cover just as you do the filter O-ring. That helps it "seat" a little better in the lands in the cover. The torque on the three screws for the cover is 9 or 11NM. Not much at all. My fasteners are allen head, not torx.

I'll be up your way this afternoon on the River Road and across the rivers on the ferrys back into MO. Got the afternoon off and I'm going to enjoy the ride.
 

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Also, a number of people have had the heads of the filter bolts snap off, even using a torque wrench!

I sold quite a large number of sets of better screws to prevent them breaking. The standard ISO grade 8.8 screws BMW uses are just about at their limit when tightened to the stated 10NM. The grade 12.9 ones I was selling are not even close at that torque. (The grade number is stamped into the head of the screw)

From a major metric fastener company's technical data:
Tightening torque, lubricated, for a M6 screw to reach 90% yield value of the screw:

Grade 8.8=9.9 NM
Grade 12.9=16.5 NM

You can see that BMW is recommending a torque for the standard grade 8.8 screw that will go over 90% of the yield rating for the screw! That leaves NO room for error. 10% overtightening can easily overcome the yield strength of the screw.
 

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I believe your torque numbers but don't believe it's the problem you indicate - I've been reading posts for 6 years, religiously read the old board, and don't remember posts about filter cover bolts snapping....... did a search and again come up with nothing.....

Perhaps I'm having a senior moment ........
 

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There were several people who had the heads snap off. Grif was one.

There is just no room for error on these bolts, and anyone not using a torque wrench is highly likely to over torque them. Even using a torque wrench is dangerously close to yield on the screws using BMWs' torque of 10Nm. I would not go over 9 Nm with stock bolts.
 

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Where to get Dave's ISO grade 12.9 Screws?

Where or how to get Dave's ISO grade 12.9 Screws?

Matt Kas
Chandler, AZ


dshealey said:
Also, a number of people have had the heads of the filter bolts snap off, even using a torque wrench!

I sold quite a large number of sets of better screws to prevent them breaking. The standard ISO grade 8.8 screws BMW uses are just about at their limit when tightened to the stated 10NM. The grade 12.9 ones I was selling are not even close at that torque. (The grade number is stamped into the head of the screw)

From a major metric fastener company's technical data:
Tightening torque, lubricated, for a M6 screw to reach 90% yield value of the screw:

Grade 8.8=9.9 NM
Grade 12.9=16.5 NM

You can see that BMW is recommending a torque for the standard grade 8.8 screw that will go over 90% of the yield rating for the screw! That leaves NO room for error. 10% overtightening can easily overcome the yield strength of the screw.
 

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Drain oil and re use it.
Cringe.

Think I’d rather listen to finger nails across a black board.

Bob
 

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This is an old thread with lots of good basic information (similar question recently asked) that I happened upon and thought I'd add just a little to it. Be careful reusing "old" oil as the container, if it's the one that you usually use to catch the old oil, might be contaminated.

Because the listed torque is so low for the 3 bolts, and I've replaced them with the ones that Dave had, I tighten with my fingers and then just a very slight snug with the wrench. If everything is clean, it seems very easy to tell if they are not tight enough.
 

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I don't see the need to oil the cover "O" ring.
Nothing slides in fitting this but miss-alignment or pinching would create a leak.
When reinstalling, hold the cover up against the mating surface and tighten the
bolts finger tight prior to torque. Don't allow the cover to twist or maybe the rubber
would come out of the groove.
+1 for Dave's bolts. Still going well thanks Dave.
The oil filter seal on the other hand does require a smear of oil prior to tightening.
 

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Kevin, I had the exact same thing happen a couple yrs ago. Being under warranty and a neuby, I put in new oil and sacrificed the oil. Most likely we both pinched the O-ring, although when I opened mine up I could not tell for sure. I am extra careful in making sure the O-ring seats to the groove, but notice that it seems like they always have a twist to them when removed from the bag. I oil the O-ring like others and try to make sure that it's seated. Trying to align the cover with minimal repositioning may also help. Good luck.
 

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Hilton said:
+1 for Dave's bolts. Still going well thanks Dave.

What are "Dave's bolts"? Why are they different? Who is Dave?

Inquiring minds want to know...

Cheers,
 

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Glenn, "Dave" is our own David Shealey, who has contributed much to this Forum over the years. If you scroll up to post #6 in this thread you will see what "Dave's bolts" specs are.

John
GlennM86 said:
What are "Dave's bolts"? Why are they different? Who is Dave?

Inquiring minds want to know...

Cheers,
 

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Sorry for being stupid but for what do you need stronger bolts (maybe I will learn)? I have always fastened these oil filter cover bolts using "screw driver" type of wrench simply not letting me to over-torque the bolts. Never have seen a drop of oil on the floor either.

What is the need to over-torque everything. Those bolts will cut in to cast aluminium easier than one can think....
 
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