Stuck Fuel Tank Access Covers

[Zippy_Bird]

Hi all,

Currently in the middle of my first N9353M annual with my trusted local A/P.  All has gone well up until today.  We need to get into the Fuel tanks but someone incorrectly used "standard tank sealant" on the tank access covers versus "low adhesion sealant."  These suckers are stuck-on TIGHT!

Does anyone have suggestions or hacks on how to get these off without damage?  Any feedback is much appreciated!

Sincerely,

zippy_bird

[N201MKTurbo]

Get one of these:

https://www.amazon.com/WHLLING-Automotive-Removing-Interior-Demolishing/dp/B0CH8J1VFM/ref=asc_df_B0CH8J1VFM/?tag=hyprod-20&linkCode=df0&hvadid=692875362841&hvpos=&hvnetw=g&hvrand=18446124170768220136&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9030089&hvtargid=pla-2281435180258&psc=1&mcid=81d1c978201134429a25f682ebb546c9&hvocijid=18446124170768220136-B0CH8J1VFM-&hvexpln=73&gad_source=1
 

Tape around the cover with masking or duct tape to keep from scratching the paint. Scrape the sealant out of the gap between the wing skin and the cover with a pick or small screwdriver. This is a 1/16 inch gap or so. Then take the skin wedge and shove it into the gap pointing away from the cover. Work it back and forth while pushing it in. After you get it in, pry a bit to pry the skin up from the cover. Then pull it out and do the same thing about an inch and a half down from where you started. After about the fourth time shoving the skin wedge between the skin and the cover, it will come loose.

[N204TA]

I’m curious to know why you need to get into the tank.  They aren’t meant to be routinely opened as it’s a labor-intensive process.

[Zippy_Bird]

30 minutes ago, N204TA said:

I’m curious to know why you need to get into the tank.  They aren’t meant to be routinely opened as it’s a labor-intensive process.

Hehe.  Mooney airplanes do two things...  Fly fast and Leak!

[Zippy_Bird]

47 minutes ago, N201MKTurbo said:

Get one of these:

https://www.amazon.com/WHLLING-Automotive-Removing-Interior-Demolishing/dp/B0CH8J1VFM/ref=asc_df_B0CH8J1VFM/?tag=hyprod-20&linkCode=df0&hvadid=692875362841&hvpos=&hvnetw=g&hvrand=18446124170768220136&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9030089&hvtargid=pla-2281435180258&psc=1&mcid=81d1c978201134429a25f682ebb546c9&hvocijid=18446124170768220136-B0CH8J1VFM-&hvexpln=73&gad_source=1
 

Tape around the cover with masking or duct tape to keep from scratching the paint. Scrape the sealant out of the gap between the wing skin and the cover with a pick or small screwdriver. This is a 1/16 inch gap or so. Then take the skin wedge and shove it into the gap pointing away from the cover. Work it back and forth while pushing it in. After you get it in, pry a bit to pry the skin up from the cover. Then pull it out and do the same thing about an inch and a half down from where you started. After about the fourth time shoving the skin wedge between the skin and the cover, it will come loose.

We got ONE off using this technique.  The others... not so much.  Other suggestions?

[N201MKTurbo]

33 minutes ago, Zippy_Bird said:

We got ONE off using this technique.  The others... not so much.  Other suggestions?

You might try a heat gun.

 

[Shadrach]

I don’t think there’s any way to do it without some marring of the mating surfaces but the paint can be protected. 
 

I would buy a cheap metal 1 1/2” putty knife and grind the corners off so it’s rounded. Then grind the edge sharp.  Try to slowly work the blade in one spot. Once through slowly cut your way around the access plate.
 

[jamesm]

You maybe pass this point ... The only one or 2 times that I had to get into the tanks.  I found skin wedge and plastic scrapping tool help along with a lot patience working it and working it and then finally it starts giving way. stating the obvious you do NOT want nick or damage receiver plate inspection plate mounts to.

https://www.yardstore.com/sheet-metal-hand-tools/miscellaneous/skin-wedges

Good Luck on your project.

James '67C

[Skyland]

Yes, scraping, heat gun, guitar picks.  Be very careful not to bend the thin wing skins.  Also, leave the screws in place backing them out a few turns.  You can then apply pressure to the screw heads.  I placed a board on the screw tops with bricks to apply a constant pressure, even overnight might help.

[Hradec]

17 hours ago, Skyland said:

Yes, scraping, heat gun, guitar picks.  Be very careful not to bend the thin wing skins.  Also, leave the screws in place backing them out a few turns.  You can then apply pressure to the screw heads.  I placed a board on the screw tops with bricks to apply a constant pressure, even overnight might help.

I didnt want to mention heat gun, but that's exactly what I used. but my tanks were vented a very long time and there was to danger of fire or explosion.  heat gun was definitely  helpful along with phenolic and plastic scrapers. thin putty knives.