oil bath air cleaner

[ricoled]

Hi everyone,
I've finally traced my remaining hi-rpm problems to a restrictive air cleaner. My 280SL runs very well without the air cleaner connected.  It's an oil-bath type and I couldn't find much information on how it works and how to set it up properly.  

I've cleaned the inside components - there's a bottom cavity, then 2 round filters stacked above the bottom cavity, and a final filter sitting on the top stack that is permanently connected to the cover.  The components appear in good shape, and I cleaned them out by soaking throughly in diesel to degrease it a bit.  

Are these filters really restrictive by nature or is something else causing it to fail?  Where does the air from outside pass through? How much oil should I place since i don't see any level marks. What kind of oil should I use?  I've tried SAE 20 but that didn't work.  Engine bogs down past 3500rpm with the oil-bath connected.

If I can't get my oilbath working, the quickest fix would be to install a K&N freeflow at the risk of losing originality.  Or replacing my cannister with an MB paper element-type?  Any comments?  

thanks, Martin

'68 280SL
'82 240D
'90 260E

[Cees Klumper]

I would guess that the oil bath filters were introduced to cope with extremely dusty road etc. conditions. This may have been relevant in days gone, but I suppose that your road conditions are very similar to, for example, conditions in Florida? If you can try out a K&N filter first, attached directly to the intake manifold, you can test the operation of a non-oil bath filter. If it's ok, and you want the original look, you can always then get the proper canister, and maybe even fit the K&N part in there. Or a regular MB one, or another K&N one.

ALSO: try a search on the site (see top of this page, second to right option):
http://index.php?topic=499,bath,filter

Cees Klumper in Amsterdam
'69 white 280 SL automatic

[Naj ✝︎]

Hi, Martin,
Engine oil is normally used. There is a blob of paint at the botton of the canister. Only fill to cover the paint mark.
Check to ensure inlet is not clogged up. It is at the back of the canister, i.e. the side facing the passenger compartment!!
The space around the opening should also be clear and uncluttered.
I recently replaced mine with the paper element type but you need the correct canister for that. Not easy to come by as different from saloons.
Hope this helps.
naj

'Kloines Scheisserle'
65 230SL
68 280SL

[Benz Dr.]

I'm sure I have a complete canister assembly that uses the paper filter. I wouldn't put a K&N filter on a go kart , let alone a 280SL.

Dan c   SL Barn

Daniel G Caron