M30 Oil filter woes

[Mr Project]

Ok, I have a weird issue with my M30...Oil filters don't fit! The replacement filter BMA sent me was nearly 1/4 inch too tall to fit in my housing. I wrote this off as weird, but since there was a WIX sticker on my housing, I thought maybe the housing had been changed.

So I bought a WIX filter with the # from the sticker on my housing...57132, which is also the stock # listed for my M30. It is also too tall! The filter body is between 1/8 and 1/4 inch longer/taller than the existing filter, and it prevents the 'lid' on the housing from sealing down.

In this case, I was able to trim down the rubber gaskets on each end of the WIX filter to get it 'short' enough to fit...it still compressed the filter down more than I would like when I tightened the bolt, but it seems fine, with no issues over a couple hundred miles.

The filter I took out was a full metal can-type that is slightly shorter than these replacements, and has no manufacturer or brand indication on it...

I hate to keep having to modify filters to get them in my car...can anyone shed some light on this for me? I'm confused, as usual. :)

Armen

[George M]

the height of the cannister inside. This is deliberate. If it were line-to-line as you secured the lid on...there would be no pre-load and oil pressure within the cannister would push by the two end seals. As you tighten the carriage bolt the corregations of the oil filter will compress if not distort slightly which is fine...this will ensure that the two end seals will not cave to oil pressure and all oil flow will past through the paper element. A further side bar to help those change their oil on their M-30...first thing you should do as you loosen the cannister carriage bolt is not pull the lid right off as you remove the bolt. First remove the bolt which will create a leak path down into the crankcase thereby when you remove the lid you won't spill oil all over.
HTH,
George

[Mr Project]

Yeah, the 'loosen the bolt and wait' became pretty obvious when I saw how the housing looked inside. :)

So maybe that's why these paper filters are longer than the metal canister type...obviously the metal canister wouldn't compress.

I was just really surprised at how much they would have to compress in order to seal that lid. I guess it makes sense, though.

Thank you!

[George M]

your old oil filter you will notice the pleats in the filter will be wavy. This is because the filter is compressed when you tighten down the lid.
Cheers,
George

[Bimmer Nut Ed]

Thanks George. I didn't know this stuff either. Always wondered why the filter was seemingly too tall.

And especially the "pull the bolt out to drain the oil down" part. I always loosened it and waited forever! And still had a mess!