# Can an aircraft owner legally replace an oil quick drain valve?

The quick drain valve on our older Mooney has started leaking and making a bit of a mess. We went to our local shop to asked them to schedule to replace it for us and they told us they are booked out several weeks and turning away any smaller jobs due to being understaffed -_-

I mentioned we do our own oil changes and he suggested that if we were handy enough to handle an oil change we could just remove the quick drain and replace it with an original plug and he was happy to give us one for free. That would get us to our next oil change and we could get it replaced then.

Part 43 allows owners to do the oil changes and replacing the quick drain valve with a plug looks to be basically identical to the oil change process if you didn't have a quick drain valve in the first place: remove the plug, catch the oil, replace plug, add new oil. But if I'm going to down that route anyway why not just grab a new quick drain off of aircraft spruce and put that in instead of the plug?

Are we on the right side of owner maintenance if we replace the quick drain with a plug as the A&P suggested? How about if we replace the quick drain with a new one? Or should we get a sign off from an A&P

• This is why we need more mechanics on SE. – Ryan Mortensen Jun 15 '16 at 23:39
• @RyanMortensen There is a share button that you can use to email this question to somebody. If you know a good mechanic, you might throw this over to them. Maybe it would entice them to join. – Jay Carr Jul 25 '16 at 16:43
• As an A&P familiar with 14 CFR 43, Appendix A, I do not consider replacing an oil quick drain plug to be included in the list of the preventative maintenance that an owner or operator is authorized to do. This is my informed opinion; I am not the FAA. – J Walters Sep 8 '16 at 0:20
• @JonathanWalters I think you're probably overall right. Now if I could just solve the "A&P's won't do the small tasks in my area" problem that would be awesome. We've been outright turned away or told it would be 2-4 weeks for every small issues thing we've wanted to have a mechanic since purchasing. Seems like the local shops don't want to do anything except annuals and avionics installations that bring the \$ – John Sep 8 '16 at 0:31
• Another way to ask this is: "how can the FAA determine that someone other than an A&P replaced an oil quick drain valve?" – acpilot Sep 9 '16 at 0:27

This is what the FAR allows you to do as preventive maintenance if you are not a certified mechanic:

(c) Preventive maintenance. Preventive maintenance is limited to the following work, provided it does not involve complex assembly operations:

(1) Removal, installation, and repair of landing gear tires.

(2) Replacing elastic shock absorber cords on landing gear.

(3) Servicing landing gear shock struts by adding oil, air, or both.

(4) Servicing landing gear wheel bearings, such as cleaning and greasing.

(5) Replacing defective safety wiring or cotter keys.

(6) Lubrication not requiring disassembly other than removal of nonstructural items such as cover plates, cowlings, and fairings.

(7) Making simple fabric patches not requiring rib stitching or the removal of structural parts or control surfaces. In the case of balloons, the making of small fabric repairs to envelopes (as defined in, and in accordance with, the balloon manufacturers’ instructions) not requiring load tape repair or replacement.

(8) Replenishing hydraulic fluid in the hydraulic reservoir.

(9) Refinishing decorative coating of fuselage, balloon baskets, wings tail group surfaces (excluding balanced control surfaces), fairings, cowlings, landing gear, cabin, or cockpit interior when removal or disassembly of any primary structure or operating system is not required.

(10) Applying preservative or protective material to components where no disassembly of any primary structure or operating system is involved and where such coating is not prohibited or is not contrary to good practices.

(11) Repairing upholstery and decorative furnishings of the cabin, cockpit, or balloon basket interior when the repairing does not require disassembly of any primary structure or operating system or interfere with an operating system or affect the primary structure of the aircraft.

(12) Making small simple repairs to fairings, nonstructural cover plates, cowlings, and small patches and reinforcements not changing the contour so as to interfere with proper air flow.

(13) Replacing side windows where that work does not interfere with the structure or any operating system such as controls, electrical equipment, etc.

(14) Replacing safety belts.

(15) Replacing seats or seat parts with replacement parts approved for the aircraft, not involving disassembly of any primary structure or operating system.

(16) Trouble shooting and repairing broken circuits in landing light wiring circuits.

(17) Replacing bulbs, reflectors, and lenses of position and landing lights.

(18) Replacing wheels and skis where no weight and balance computation is involved. removal of the propeller or disconnection of flight controls.

(19) ...

(20) Replacing or cleaning spark plugs and setting of spark plug gap clearance.

(21) Replacing any hose connection except hydraulic connections.

(22) Replacing prefabricated fuel lines.

(23) Cleaning or replacing fuel and oil strainers or filter elements.

(24) Replacing and servicing batteries.

(25) Cleaning of balloon burner pilot and main nozzles in accordance with the balloon manufacturer’s instructions.

(26) Replacement or adjustment of nonstructural standard fasteners incidental to operations.

(27) The interchange of balloon baskets and burners on envelopes when the basket or burner is designated as interchangeable in the balloon type certificate data and the baskets and burners are specifically designed for quick removal and installation.

(28) The installations of anti-misfueling devices to reduce the diameter of fuel tank filler openings provided the specific device has been made a part of the aircraft type certificiate data by the aircraft manufacturer, the aircraft manufacturer has provided FAA-approved instructions for installation of the specific device, and installation does not involve the disassembly of the existing tank filler opening.

(29) Removing, checking, and replacing magnetic chip detectors.

(30) The inspection and maintenance tasks prescribed and specifically identified as preventive maintenance in a primary category aircraft type certificate or supplemental type certificate holder’s approved special inspection and preventive maintenance program when accomplished on a primary category aircraft provided:

(i) They are performed by the holder of at least a private pilot certificate issued under part 61 who is the registered owner (including co-owners) of the affected aircraft and who holds a certificate of competency for the affected aircraft (1) issued by a school approved under § 147.21(e) of this chapter; (2) issued by the holder of the production certificate for that primary category aircraft that has a special training program approved under § 21.24 of this subchapter; or (3) issued by another entity that has a course approved by the Administrator; and

(ii) The inspections and maintenance tasks are performed in accordance with instructions contained by the special inspection and preventive maintenance program approved as part of the aircraft’s type design or supplemental type design.

(31) Removing and replacing self-contained, front instrument panel-mounted navigation and communication devices that employ tray-mounted connectors that connect the unit when the unit is installed into the instrument panel, (excluding automatic flight control systems, transponders, and microwave frequency distance measuring equipment (DME)). The approved unit must be designed to be readily and repeatedly removed and replaced, and pertinent instructions must be provided. Prior to the unit’s intended use, and operational check must be performed in accordance with the applicable sections of part 91 of this chapter.

(32) Updating self-contained, front instrument panel-mounted Air Traffic Control (ATC) navigational software data bases (excluding those of automatic flight control systems, transponders, and microwave frequency distance measuring equipment (DME)) provided no disassembly of the unit is required and pertinent instructions are provided. Prior to the unit’s intended use, an operational check must be performed in accordance with applicable sections of part 91 of this chapter.

• I don't see an exact match, except for possibly "(30) The inspection and maintenance tasks prescribed and specifically identified as preventive maintenance in a primary category aircraft type certificate or supplemental type certificate holder’s approved special inspection and preventive maintenance program when accomplished on a primary category aircraft provided: ..." Someone with access to the maintenance manual would have to check to see if it is listed there. – Lnafziger Sep 7 '16 at 19:16
• I would have my doubts about that. No maintenance manual for any aircraft that I have ever worked on has ever said that replacing a non-consumable part on an engine is preventive maintenance. – Juan Jimenez Sep 9 '16 at 6:28

Just replace the drain at the shop in front of the A&P

• Not that simple. The A&P needs to ensure all work is accomplished in accordance with appropriate data and then sign off the work for return to service. – J Walters Sep 8 '16 at 0:19
• Sure. But this is a question about the owner not the A&P – rbp Sep 8 '16 at 0:43

FAR Part 43, Appendix A, tells you exactly what preventive maintenance you can do as the owner of an aircraft that is not used for commercial service.

• could you consider quoting here the relevant parts of the FAR? – Federico Sep 1 '16 at 8:14

That's an interesting question. In reality, anyone can replace a part on their own A/C, but to be legal, you must be under the supervision of a certificated A&P and get it inspected/signed off. FAA, part 43.3 (d)

• Welcome to Aviation.SE! Can you provide any sources that back up this answer? – fooot Jun 24 '16 at 19:31
• Larry's answer is almost correct. The section he refers to (14 CFR section 43) lists preventive maintenance that the pilot or owner may do and make the appropriate log book entries. Under this section no A&P supervision is required. So it is clear that the pilot/owner can change the oil which involves removing the oil drain. The question is: does this permit him/her to use a different plug as he finishes? If it is the same part number as the OEM plug I vote yes. – Skip Miller Jun 24 '16 at 22:48
• (d) A person working under the supervision of a holder of a mechanic or repairman certificate may perform the maintenance, preventive maintenance, and alterations that his supervisor is authorized to perform, if the supervisor personally observes the work being done to the extent necessary to ensure that it is being done properly and if the supervisor is readily available, in person, for consultation. However, this paragraph does not authorize the performance of any inspection required by Part 91 or Part 125 of this chapter or any inspection performed after a major repair or alteration. – Larry Jun 24 '16 at 23:00
• This, in my view, constitutes an alteration. – Larry Jun 24 '16 at 23:07
• Part 43, appendix d. Read the regulation. As soon as the pilot installs the OEM plug he brings the A/C back to Mfg specifications. To install the quick drain is legally an alteration and requires an A&P. – Larry Jul 26 '16 at 19:17

Read FAR 43 Appendix A thoroughly and find (23) which says:

(23) Cleaning or replacing fuel and oil strainers or filter elements.

A quick drain valve is considered an oil strainer.

Create a logbook entry and have a beer.

• Welcome! Just to play devil's advocate, do you have a FAR reference showing that a quick drain plug is considered an oil strainer? – FreeMan Sep 7 '16 at 17:58
• I'm sorry but you just copied another answer... – ymb1 Sep 7 '16 at 19:44
• A drain valve is NOT an oil strainer. An oil strainer is a mechanism contained within the pressure portion of the oil system used to strain oil. It's function is similar to, and usually in place of, that of the oil filter used on many piston aircraft and cars. – J Walters Sep 8 '16 at 0:18