BMC Filters

[RussRamz]

As many of you know, I had my BMC filters installed when my Kelleners Motor Kit was installed over one year ago. In the fall I installed RPI scoops and realized some gains when I ran the car with my vBox.

Over the past few weeks I noticed the power doesn't seem to be what it used to be and I realized that RPMs seem to fluctuate at idle occasionally. I thought it might be time to check the cleanliness of my filters, so after a couple minutes I removed them and realized it was the filters! They were really dirty. I SPECULATE that with the scoops installed and me driving my car in all weather conditions, I might have consumed a lot of dirty mist from rainy road conditions where it might not have been consumed otherwise. I tapped the filters out on a white shop towel and the white of the shop towel turned to black. These things were DIRTY. I didn't have a cleaning kit, so I just did the best I could shaking out the filters and picking the dead bugs out of the pleats. Moments after firing up the car with the half-a$$ed cleaned filters and driving off, increased performance was immediately noticeable.

So, one week ago I ordered a BMC filter kit, cleaned them and oiled them per the instructions. After putting them in the car, performance dropped off dramatically. It felt as if the car was stuck in P400 mode. I figured I overoiled them. So, once again I have them out, cleaned them with the detergent, but it seems the detergent that comes with the cleaning kit doesn't do the job of removing all the oil. So I have cleaned them again using a super diluted mixture of dawn dishwashing detergent to break up the oil and get the things cleaned. It worked. I'm going to lightly mist the filters with the oil this time instead of what the instructions recommend. Otherwise, I'll order another set of filters.

Has anyone else out there had problems cleaning and re-oiling your filters? Are there any recommended techniques to getting these things back to the original performance status without buying a new set? I'll update with my results and/or decision to get a new set. Oh well, I guess it's a cheap solution to just buy a new set if this doesn't work.

[snowball]

I added my BMC filters (and removed the carbon filters) right after the 1200 mile service. This past weekend I added the RPI scoops and the block off plates (now at 10K+ miles). I was going to get a new filters, but Eloy at RPI told me about the cleaning kit, said they should last 35K-40K miles before even needing to use the cleaning kit. He did mention that many people do tend to over oil them to get the red color back.

When I installed the block off plates I saw that my BMC filters were just slighly dirty so I didn't clean them. Just wondering if you also added the block off plates?

[RussRamz]

I have not added the block off plates. I can only assume mine became so dirty with the driving in the misty rain.

Checking the filters today, they seem to be clean and dry. I will 'mist' the filters with as little oil as possible and see if that helps.

[///Marshall]

Good info. It sounds like you drive the hell out of your M6.
Last I checked my filters were still clean. When they do
get dirty I'll probably just eat it and buy new ones.

[m6ontheway]

I should check mine too...I have over 16k on the clock...I think I did mine around 3k...if they are dirty I am just going to buy new ones cause I am ******ed.

[Cosmos]

Russ,

Did you clean your AM's as well? I would check to see if the oil got on the sensors.

Also for me, I don’t like pissing money away; however, I have NEVER been able to properly clean an air filter. I just throw them away when they get dirty and buy new ones.

For me, it is usually once every 15 months, so the $100 is not that bad.

[T Bone]

No problems here with the BMC + RPI Scoop combo.

I think you hit the nail on the head Russ....the scoops shoved in stuff that otherwise wouldn't be in there.

Nature of the beast. I have a cleaning kit and I am worried about overoiling too....

Then again you are dirty.

[RussRamz]

Originally Posted by T Bone

Nature of the beast. I have a cleaning kit and I am worried about overoiling too....

Then again you are dirty.

So, using the Dawn(tm) Dishwashing Soap trick seems to work. I lightly misted the filters from a distance of about 24 inches against a background of white paper towels to judge coverage of the filters since they are difficult to determine how much oil covers them. Once the paper towels showed a good level of absorbtion, I flipped them over and repeated. Judging from how much oil I sprayed this time around, I definitely over-oiled on my first attempt.

The car runs MUCH better now. I will still likely buy another set of filters, but maybe not in time for Sweden this weekend.

[RussRamz]

Originally Posted by Cosmos

Russ,

Did you clean your AM's as well? I would check to see if the oil got on the sensors.

Also for me, I don’t like pissing money away; however, I have NEVER been able to properly clean an air filter. I just throw them away when they get dirty and buy new ones.

For me, it is usually once every 15 months, so the $100 is not that bad.

I unscrewed the AFMs and didn't see any contamination on the coils, but I think I will pull both out and give them a good cleaning for good measure. I want my car running tip-top for Sweden at the end of the week. I plan to use carb cleaner unless you can recommend another method.

[MCarRacr07]

Perhaps things have changed and albiet a different car.
I had BMC filters on my E36 M3 track car....in fact I brought them back from Italy back in 95 as I could not find them here....my problem with them was exactly what you described...getting them clean again. At first I thought I put too much oil(which I probably did)...but even after trying again...they were a ***** to clean out....had much better results with K&N in the cleaning process....from a performance point of view I could find no fault with them...nor any better performance really.
The cleaning aspect was the PIA.
Just my 2 cents
S