C182J Fuel Bladder Replacement Guidance

Bentley

Filing Flight Plan
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bentley
My fairly new to me 1966 182J has started leaking what appears to be fuel combined with adhesive from the left wing. It only leaks when I have roughly more than 25 gallons of fuel in the wing.
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Digging into the logbook, I believe it was last replaced in 2002.

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I have 3 questions:

1. Any reason to think this isn’t a leak/crack in the bladder? The area around the fuel senders is dry and doesn't appear to be the origin of the fuel. I've also accidentally overflowed refueling and had fuel get around the bladder and leak its way out; this is not the result of such pilot error.

2. Who would you get to do the replacement? The shop that has done the past two years’ annuals has made it very clear that they have little interest in doing this work (their bread and butter is avionics). Is this the sort of thing a mechanic that has been around for a bit can do even if they aren’t doing them every couple of months? Or should I be looking for someone that is deeply familiar with the work to be done?

3. What other questions should I be asking? I'm new to aircraft ownership and have been reading a lot online about fuel cells. I found this great article on the steps involved in replacement (https://www.cessnaflyer.org/magazin...nical/step-by-step-fuel-cell-replacement.html). I've also read plenty about the pros/cons of repair vs. replacement as well as the many opinions on which brands to go with.
 
1. Any reason to think this isn’t a leak/crack in the bladder?
There's always a chance it could be leaking at a fitting, etc. However, with proper troubleshooting finding the cause usually is not that difficult.

2. Who would you get to do the replacement? The shop that has done the past two years’ annuals has made it very clear that they have little interest in doing this work (their bread and butter is avionics). Is this the sort of thing a mechanic that has been around for a bit can do even if they aren’t doing them every couple of months? Or should I be looking for someone that is deeply familiar with the work to be done?
Any mechanic is capable of performing the task. Its not too complicated in the big picture. But as noted by your shop its not in the top 10 list of work to perform as there can be some gotchas like stuck panel screws, etc. which can extend the job. Perhaps your shop can recommend some local mechanics who could look into this issue?

3. What other questions should I be asking?
Knowing how the mechanic will verify where the leak is coming from is important. However, some mechanics can prefer to open everything up or remove the cells then look for the leak. I've done both ways depending on the circumstances which can be dictated by the age of the fuel cell. Good luck.
 
It's likely you have a fitting or hose leak. The bladders should last 2-3 more decades.
I just had this happen to me 2-3 years ago, and it was an easy and cheap fix.
Good luck.
 
Cessna has a Service Directive from the ‘70’s that details a method of leak testing. Long range tanks?

OBSERVE SAFETY PRECAUTIONS

1. Fill tanks. Left must be full. Open bottom panels in the area. Caps tight.

2. Fuel Selector BOTH

3. Jack RIGHT side

4. Fuel will run from RIGHT tank , through Selector and into LEFT tank.

This will test the the integrity of the upper bladder and the seal between

bladder and the Skin.


Notes: Fuel WILL run out from the wing Vent as well as the leak source!

Monitor carefully and at first sign of leak stop transfer by lowering

jack.


Review Parts Manual. Some installs use a gasket and others rely on the

bladder. There may be a sealant authorized here too.

DO NOT attempt to use air pressure to check unless there are specific

precautions given to avoid SEVERE damage. Having experienced folks do this

Is helpful ..LONG Arms and taping the skin/ adapter edge will help.

Long Range Tanks have vent tubing in the bladder that is often misinstalled.


Finally; the next time the Fuel Strainer is checked you will likely find.

some residue. It’s skin if you didn’t tape the edges!,
 
Pull headliner and check rubber hose condition. Problem is the rubber nipple out of the bladder gets rock hard.
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My leak was from a crack in the fuel tank.
The fuel lines above the headliner were in terrible shape but not leaking yet.
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Note that regardless of the source the leaks generally present at the aft

inboard area near the sump.
 
Imagine if the plane instead had G100UL. The paint would be stained down to the aluminum.
 
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