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Air Filter and Box

I have a RV 7 with a O-320 (160 Hp) engine. I am in the middle of my first condition inspection (Supervised)and ran across a potential problem I am not sure how to correct. I have attached pictures, but simply, Thee is a cut out a small section of the K&N air filter to fit due to the accelerator pump off the bottom of the carburetor. I feel it is a safety issue if that RTV comes loose it goes right into the carburetor. What options are there to fix this as a new filter will have the same issue?
 

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Your filter is notched and sealed per instructions, seems a little goofy, but it works. Have run this setup as have countless others for many hours with no problems that I’m aware of.
 
I agree that its pretty "average" to look at but it does work and in many years of maintaining RV's I've never seen any issues with this sealant moving if applied correctly.

Clean or replace the filter and carry on flying.
 
O-320, I was able to fit a K&N Engine Air Filter: High Performance, Premium, Washable, Industrial Replacement Filter, Heavy Duty: E-3322 without needing to trim and seal for the accellerator pump bump.

YMMV.
 
My RV-6 with 320 has been flying 25-years and over 3,400 hobbs hours with the setup you are showing.

My filter has been replaced three times over the past 25-years. I had BLACK RTV like the red you have on the first two filters. I used that because that is what the early instructions told us to do. About a year ago, the filter was replaced but ProSeal was used as that is what Van's Aircraft currently recommends.

The filters are reusable but they still do not last forever. I tried the other part number recommended here for the 320 but did not like the way it fit. I sold that filter here and used the one Van's recommended for the 320 FAB some 25-years ago.
 
Thank you all for the information. That really helps me a lot when putting it back together. I looked all over in the Vans sight and could not find the reference supplied above. I will probably get a new filter and do it per the Van's instructions supplied.
 
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Looks like the original builder followed the build manual. Sounds like a case of judging the original builder on the forum for the whole community to see before finding out that it was done as per instructions. Just saying? Builders manuals are easy to come by.
 
I think I would be more concerned about the apparent rivet to edge spacing on the plate in the bottom of the picture. I'm not sure what I am looking at there, but what appears to be rivets sticking up are right on the metal edge.
 
The filter element looks dry. It should be oiled with the correct red oil before use. K&N sells the oil as well as selling the filters.
 
Build a New "No Cut" FAB

You can build a new "no cut" FAB that allows the filter (and upper mount plate) to be installed without having to cut the notch for the carb accelerator pump bulb.
By using Vans new FAB kit and adding an approximately 0.700" spacer between the bottom of the carb and the FAB top mount plate, the mount plate and filter will fit nicely and not require a cut out.
Did this mod on an O-320 with the old style FAB. There is a degree of difficulty in doing this on an RV-A that already has the lower cowl air inlet snorkel complete....but is can be done.
I purchased spacers from Airflow Performance and milled them as needed to achieve the right stand off from the upper mount plate to the carb accelerator pump bulb, the gap was about 0.030" once torqued up with the mount hardware. There was plenty of vertical and lateral space between the lower cowling and the FAB even after lowering the FAB 0.700".
 
Note-check that you have the vertical space under the filter housing for a spacer collar. Some lower cowls are tight fit down there.
 
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