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Castrol Foam Filter Oil or Amsoil High Tack Foam Filter Oil


Boise ID area
For the foam air cleaner maintenance, CC states to wash out the foam filter and apply Castrol Foam Filter Oil or Amsoil High Tack Foam Filter Oil.

I cannot find either.

The stock foam air filter comes ready to use with some unknown extremely sticky clear substance. The filter is so impregnated that I'm surprise air will pass thru.

Thanks, I'm familiar with the car care products just worry about engine warranty. But in a few months it won't matter.

Was just wondering if anybody knew of these particular products.
Call CC and ask for some advice. I've used K&N and UNI foam filter oil plus the old standby of STP oil add and straight 30W. But CC may be concerned about oil vs their foam element compatibility.

Bar oil? Isn't that just engine drain-oil?

Can be for some of us...but Husqvarna and others sell a virgin based product (mineral but veggie oils are available for others who are sensitive). UNI foam oil works. What type foam filter CC installed should drive the wetting agent. We use vegetable based oil to cut up harvested moose with a chainsaw.

Pay particular attention to oiled foam filters flying in sleet/snow or on floats when cold (parked or running). I've had the Brackett units cover quickly and retain water or ice. Sure anything will eventually get covered but other media seems to not retain it as much. A drop in manifold pressure is the first indication. Non-fuel injected have an alternate heated air source; some FI have an alternate air door that opens under suction.

Good advice, thanks. The air filter for the CC is a very porous type of media compared to a dirt bike type filter. Even though I call it a foam filter, which it is, the foam is not dense. And a bottle of Lucas Foam Filter oil is half of a new filter and can probably get numerous cleanings out of a bottle when the time comes.



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Foam fits oddly shaped openings. Makes it popular for press fit or pre-filtration applications. One check for effective filtration is to wipe downstream of any filter with a rag and cleaner looking for bypassed material, especially if some of the wetting agent escapes the filter and attracts bypassed dirt.

Here's one manufacturer's opinion on various filter media: http://donaldsonaerospace-defense.com/library/files/documents/pdfs/007217.pdf

You are correct but I'm kind of stuck with this configuration. I will definitely be watching 'the backside' (of the filter) for any contamination as I try the Lucas oil.
If your in a gritty inviorment then oil it. I like dry paper elements on my land plane. My J4 on floats hasn't had any filter on it for 14 years now. Eats bugs and rain/snow just fine. I like the couple extra hp I get from unrestricted air.

A standard brackett air filter element will eat up to an inch of manifold pressure in my experience. That's compared with none or Donaldson the same day same plane. The old flocked wire filters like Air Maze probably passed plenty of air.

Uni Filter (link) sells both coarse, fine, and dual layer foam sheets for owner produced parts. If debris passes the existing foam air filter there may be options to double up the layer or replace with a finer or multi pore product.

Install a manifold pressure gauge to note any flow change and detect carb ice.

K&N oil is for cotton paper elements.
Thanks for that heads up. Have had a recharge kit around here for years from a friend I use to help with his RV4. An EX2 owner comes over and helps do the condition inspection on his and used this kit. I never even thought about it. I read the label today and see I need to get the right stuff and let my son use this on his truck.
All the Carbon Cubs out there use oiled foam air filters? Nobody in the aftermarket has come out with something better? There's a business opportunity for somebody with a little spare time!
used my little foam air filter on my 90 for over 15 years, seems to work just fine, wanted a donaldson because some say you get more rpms but for 100 bucks just going to keep using my foam one. i do use soap and hot water in a pan when i rinse it out and not gas. and if i would ever be in a bind i can go to macs and buy a 4foot by 8 foot sheet for 15 bucks. 10 lifetime supply. dont fly in the rain but i cant imagine rain is good for paper filters either. a 1/2 of a pint of that foam oil will last a long time. quart will last a lifetime. neighbor kid likes racing his motorcycle, wont use nothing but a foam filter with a touch of oil.
Everything was oil bath, then autos went dry paper and outdoorsy engines like lawn mowers and dirtbikes went oiled foam. Because they sit in the rain? Maybe K&N use oil mainly for water resistance.