Air Filter - clean and re-oil ?

[Dave Elliott]

Hi,

Thought I'd check my air filter over the weekend.

I have an 02 MCS that I bought last December. I'm not too sure on the recent service history, and because of this I have a question regarding the air filter element.

I took the filter out and it was reasonably clean. My guess is that the previous owner was true to his word and had it replaced before I bought the car.

I was blowing some leaves and dead insects from the intake side when I noticed there was a film of oil forming on my work bench.

The make of filter was Mahle (sorry, I didn't get the part number). Is this a standard part? Does it need oiling like a K&N type?

To me it looked like a regular paper filter, I wouldn't have expected it to be the type that needs oiling?

Any information would be most appreciated.


Cheers,

Dave

[beken]

K&N is a cotton material filter. Most cotton filters are enclosed in a metal mesh to keep it from shredding apart. As air passes through the cotton, a static charge is created which causes dirt particles to be attracted to the cotton material. The oil then causes the dirt to stick to it and allows the air to pass through. That's how I think cotton filters work.

Looking at Mahle's website, it sounds like they are an OEM filter. Which means paper. When I replaced my original stock filter, the dirty side was very dirty and looked to be greasy. Maybe they are coated in a layor of oil but they are supposed to be disposable.

I a test somewhere, it looked like the BMW/MINI OEM filter did the best job filtering dirt particles. But they also needed replacing all the time. However, MINI seems say they only need replacing every second oil service (or at Inspection time). Not sure what to make of that.

Hope that helps.



Hope that helped.

[DaFlake]

There shouldn't be oil on the OEM paper filter (flat panel). Then again, they really aren't meant to be cleaned either. I would suggest that you simply replace the filter with a new one.

[Dave Elliott]

Thanks Beken, thanks DaFlake,

My guess is that I've got an OEM filter too. It certainly didn't look like a cotton type (no wire mesh), although it did look somewhat better than other paper filters I've seem.

My concern was that after reading the service information it seemed that the replacement interval was longer than I would have expected from a normal paper filter and I didn't want to be throwing away a "special" OEM filter that just required cleaning and oiling (a la K&N).

Rather than replace the OEM filter I might splash out on a cold air intake in a little while anyway.

Dave

[DaFlake]

The only "cleanable" flat filter I have seen is a foam one. I think you would be able to tell the difference.

[beken]

Quote: Originally Posted by DaFlake (original)

The only "cleanable" flat filter I have seen is a foam one. I think you would be able to tell the difference.

Sorry, DaFlake, I'll have to disagree. The K&N panel filters are washable also.

As for the replacement interval of the OEM filters, I would say the max is 3 years. They look absolutely filthy after the first year. But the BMW/MINI filters have lots of folds (for that matter, so does the Delco-GM filters). The folds hide the pores so even though the filter looks dirty, there are lots of pores for air to pass through. Personally, I would replace the filter once a year, but I have seen at least one MINI go 3 years before they replaced the filter without any major detriment to performance.

[DaFlake]

Let me rephrase that.... The only filters that I have seen that are "cleanable" are the performance filters. There is a foam and there is a cotton filter (K &N has wire mesh) that are both made for the MINI and can be cleaned and re-oiled. Neither of these are the paper type.

Beken is correct on that.

However, I do disagree with his replacement statement (sorry bro... ) as this will be greatly determined by where you drive. When I live in Texas, you were lucky to get a year out of a filter with all the dust. Up north where there is less dust, you will be able to go longer.

Here in Germany I work near lots of heavy equipment that churns up dirt, so I have seen my filter get grimy faster than normal. It just all depends on your environment. I typically check it once a month.

The great part about a cleanable filter is that there is less waste in the environment but you do have to actually work to clean it.

[ThE.gRiZzLe]

Hi all, i know im reviving a bit of an old thread here but i didnt want anyone to have a moan for posting a new topic. Basically i thought id have an inspection of the panel filter on my cooper today and it was absoloutly mullered.... I blew out all the bugs and unsettled dirt but i think its time to have it replaced, so i was thinking ill have to make a trip down to the stealers, but rather than spending £100000000000 on a standard one, i was thinking of mabe a foam one so i can clean it in the future.

So 3 Questions...

Which one is the best?

How much is it?

Do i have to tell the insurance about it?

Thanks guys....

[Mins21]

Thought it cost about £4 or something?

I personally bought a K&N one for my MCS - breathes a bit better now.

Next up - Oil change...

[Morri7]

Quote: Originally Posted by ThE.gRiZzLe (original)

Hi all, i know im reviving a bit of an old thread here but i didnt want anyone to have a moan for posting a new topic. Basically i thought id have an inspection of the panel filter on my cooper today and it was absoloutly mullered.... I blew out all the bugs and unsettled dirt but i think its time to have it replaced, so i was thinking ill have to make a trip down to the stealers, but rather than spending £100000000000 on a standard one, i was thinking of mabe a foam one so i can clean it in the future.

So 3 Questions...

Which one is the best?

How much is it?

Do i have to tell the insurance about it?

Thanks guys....

I have a K&N panel filter on my MCS and have not thought to tell my insurance company as I was just replacing the filter with one that I can wash and reuse and also because on the box it said that there were no power gains. I can say that I have not noticed any difference in performace either. But this has got me thinking that maybe I should be telling the insurance company What do we think?

[cristo]

Quote: Originally Posted by Morri7 (original)

I have a K&N panel filter on my MCS and have not thought to tell my insurance company as I was just replacing the filter with one that I can wash and reuse and also because on the box it said that there were no power gains. I can say that I have not noticed any difference in performace either. But this has got me thinking that maybe I should be telling the insurance company What do we think?

I don't think so.

Do you tell them if you replace the oem filter with a purulator or fram one??

I'm on the other side of the pond where we don't have to tell the insurance companies
about every little thing on the car out of fear of non-coverage. Of course , if the aftermarket bits are wrecked/stolen/etc., they'll only pay for oem replacement parts.