Challenger/K&N Installation Tips

These filter elements simply bold/screw in place as exact replacements of your old air filter element.  Installation is a simple R&R procedure but do not attempt to install any filter element without first reading the instructions enclosed along with the filter as well as material printed here.  A word of caution however;  the instructions included in each box are generic and not model specific. Given the fact older Mooney cowls were somewhat hand made, some adjustments or fitting may be necessary on some models-see our FAQs. So we recommend you check with your shop and use common sense when changing any consumable part on your aircraft like an air filter element.   

While most M20 air filter installations are simple if not rudimentary and element changes can be accomplished by most owners, we advise you to only attempt replacing any filter element under the direct supervision of your A&P mechanic.  Please pay close attention as to how the old filter element was removed.  Simply reverse the procedure to install this K&N/Challenger filter, keeping in mind that it is important to obtain a proper airtight seal.  Don't make this more complicated than it is.  Most all model Challenger/K&N filter assemblies simply bolt/screw in place as a direct replacement of either the OEM paper element or the "after market" oil coated foam Brackett unit, and these elements generally reuse the same fasteners.  The important thing here is to get a good airtight seal, and therefore use the gaskets supplied as needed.  If you think in your specific installation that additional gasket material is necessary, check with your shop, call us (941-484-0800), or contact Challenger directly at (937-667-0510). 

Older "Pre-201" M20 Installation Tips:  Please keep in mind that older model 200hp M20s such as the M20E/Fs used a outwardly curved element face with a grillwork.  While some owners reuse the stock grill/frame (pic on left on a Brackett) we recommend you discard them in favor of the K&N open frame as per the pic at right as the K&N element do not require them. Again and to be clear, most owners DO NOT reuse the old grillwork as it tends to restrict airflow and thus reduce the overall efficiency of the K&N unit. 

The older 180 and 200 hp all-aluminum M20 cowls were (in essence) "hand-made" at the factory and thus may differ slightly from one individual M20 aircraft to another.  Thus the rectangular air filter opening itself (such as on the M20C/D) may need to be filed or slightly enlarged/adjusted so as to accept the CP 1176 filter body as may the 200hp M20E/F cowl to accept the 1176 element-see our FAQ Section for more details. 
Also over the years some cowls had their original nut plates removed along the way, and in their place used common #8 phillips screws maybe in place possibly with rivnuts or ?  Others however, may use similar screws but sport individual nuts and washers.  We now stock a CP-3274 Fastener Kit especially for the 180hp M20s should you need new fasteners and can't get them locally.  We typically recommend you use the same type of fasteners as found on the aircraft OEM, but in any event, use common sense and adhere to accepted FAA maintenance practices when replacing these filter elements.  Always check with your shop, and/or call us, or Challenger directly (937-667-0510) if needed. 
As always and if all else fails (smile), please read the directions and check with your local mechanic. 

Remember,  the prime factor is obtaining a air-tight seal so as to prohibit the engine from sucking foreign objects, dirt, or grit, into its induction system.   By the way, the outwardly curved CP 1176 elements (as shown just above) as used in the 200hp M20E/F obtain a tight seal with the OUTSIDE of their case, not how the element fits inside the squarish cavity in the cowl itself.