Ramp Fuel Level

[ArtVandelay]

You could get covers for the wings I believe, that would solve this problem and protect against hail damage.

[Mark89114]

Another pedantic and meaningless data point.

I have been involved in a some owner induced interior redo that has taken too long but I discovered a weeping fuel pickup in the cabin.

So I drained the tanks, let them sit, see second sentence and months later I finally get around to putting fuel back in 5 gallons at a time the first 20 gallons no problem, the last 20 I started seeing weeping and maybe what could be defined as a drip....which has since gone away.....hopefully forever.....

My thoughts are.....the fuel keeps the sealant pliable thereby preventing leaks......but at the same time my 1 repaired leak was on the bottom and always covered in fuel and I suspect most everybody else has leaks on the bottom as well as that is where the fuel is.  

 

[RescueMunchkin]

22 hours ago, PT20J said:

 Lube the center post with Tri-flow and the big o-ring with Vaseline and they will be easy to remove.

Can you give more details on this process? Which specific parts need the lube and how much lube is to be used?

[PT20J]

43 minutes ago, RescueMunchkin said:

Can you give more details on this process? 

No. You should probably have an A&P do this.

[PT20J]

1 hour ago, RescueMunchkin said:

Can you give more details on this process? Which specific parts need the lube and how much lube is to be used?

It's like the old Brylcreem commercials: A little dab'l do ya.

sbm20-229a.pdf

[1980Mooney]

1 hour ago, RescueMunchkin said:

Can you give more details on this process? Which specific parts need the lube and how much lube is to be used?

 

45 minutes ago, PT20J said:

No. You should probably have an A&P do this.

I noticed that @RescueMunchkin joined MS earlier this month and may be a new owner/aviation enthusiast.  And I see that @PT20J followed up this post with guidance per Service Bulletin 229A.   Just to be clear so there is no misinterpretation, this is the type of "Preventive Maintenance" which an owner can do. (and do it without having to first seek the approval of an A&P or having it observed/signed off by an A&P).

AOPA summarized FAA P-8740-15.  Among other things it states 

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

An owner can do a lot of things without A&P authorization including replacing seat belts, replacing non-structural fasteners, remove/clean/repack wheel bearings, grease the landing gear, replace fuel lines, remove and clean/gap spark plugs, replace cotter keys and safety wiring and more.

However it is all prefaced upon the owner self assessing that "you have the ability to perform the work satisfactorily and safely."

Although you don't need the approval of an A&P, it doesn't preclude or hurt you telling your A&P what you are planning to do.  In fact if you are a new pilot/owner it is probably good to run it past your A&P but it is still a task that you can perform.

https://www.aopa.org/news-and-media/all-news/2012/june/01/answers-for-pilots-preventive-maintenance

https://www.faasafety.gov/files/gslac/library/documents/2011/Aug/56398/FAA P-8740-15 Maintenance Aspects of Owning Your Own Aircraft [hi-res] branded.pdf

https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_43-12A_CHG_1.pdf

[1980Mooney]

4 hours ago, RescueMunchkin said:

Can you give more details on this process? Which specific parts need the lube and how much lube is to be used?

I am just going to put this out for information so that we "don't reinvent the wheel" and also remember what "advice" we have posted previously.  Let's face it - we are mostly discussing how to fly/maintain planes of similar basic design that are mainly 15-60 years old. Avionics aside, there isn't much "new" that hasn't been questioned on MS before.  Sometimes there are a lot of "best practices" which we have forgotten.

Your question of how to lubricate fuel cap o-rings has been discussed in a topic that has been going for 10 years now on MS.  Since 2013, many Mooney owners have been discussing in the same thread how to lubricate and replace the o-rings on the fuel caps.  The thread also includes, on page 1, detailed instruction from our Beechcraft friends at CSOBeech on how to replace o-rings on the same type Shaw fuel caps. (It does require some disassembly of the cap locking mechanism)

https://csobeech.com/files/O-RingChange.pdf

https://csobeech.com/o-Rings.html

I AM NOT ADVISING YOU TO CHANGE ANYTHING, but if, after inspection per SB-20-229a, that you discover that your o-rings are deteriorating, then discuss it with your A&P.  He might allow you to change them "with supervision", inspect and sign off.  After all, taking "preventative maintenance" action to keep water out of your fuel is a safety benefit.  And the FAA Circular states "Owners and pilots must use good judgment when determining if a specific function should be classified as preventive maintenance."

Lastly, in 2022 on the last page of that same thread, @PT20J shared his fuel cap lubrication recommendations.  I assume these are still his recommended "best practices":

"If you spray a bit of Tri-flow on the shaft and work it a few times every so often it keeps the center o-ring lubricated and pliable. If you keep some vasiline or DC-4 on the large o-ring, it also makes it last longer. I tried EZ Turn, which lasts longer, but it’s too sticky. A lot of mechanics take the easy way out and just replace them every year. I had the black ones on my first plane for 7 years and kept them lubricated and they never were a problem. You can tell when they’re shot — they develop radial cracks."

Edited September 28, 2023 by 1980Mooney

[PeteMc]

Looks like the discussion has widened, but going back to your original question...  Have your tanks been resealed or are they really the original sealant.  If they have been resealed, the there is not as much need to keep the tanks full.  Yes, the general rule of keeping the tanks full is probably the best course of action - when you can.  But as others have recommended, if you think you're going to take a trip with the family soon, then don't top off.  In the off seasons when you or maybe you and your wife or a friend are the only ones flying, then go ahead an keep the tanks full.

 

[Jim Peace]

I wish the doc would come back and put his 2 cents in. 

[tmo]

12 hours ago, 1980Mooney said:

if, after inspection per SB-20-229a, that you discover that your o-rings are deteriorating, then discuss it with your A&P

And then ping @OSUAV8TER about his fuel cap kits: https://www.gallagheraviationllc.com/Aircraft-Fluorosilicone-Fuel-Cap-Kits_c_36.html

[Pinecone]

And while you have them apart, the Marsh Bros teflon washers are a good idea