M20K Fuel Tanks - Dry out when not full?

[tpeterson10]

I've heard that it's not good to leave the fuel tanks below full because the sealant in the tanks can dry out.  This can lead to needing to reseal the fuel tanks prematurely. 

 

Curious if this is an issue?  How long can the fuel tanks be below full for this to happen (if it's an issue)?

 

Thanks.

[clh]

I have heard that heat is the main issue with empty tanks.  ie if the wing sets in the sun empty, it degrades the polymer faster.   I think this is also true for the older polymers.  I think the new ones are more resistant.

 

I am just an old chemical engineer, I did not sleep at a holiday inn express last night......

[BobAustin]

My tanks are rarely left full and have no leaks since I bought the plane in 1985...live in Texas where it is hot.  But I am always hangered.

[carusoam]

Old chemical engineers are the best!

-a-

[gsxrpilot]

I've heard and wondered about the same thing.  I'm in Texas (HOT), but always hangered (still hot), and I always keep the tanks full. Dose anyone see a problem with this strategy? 

 

M20C - no bladders, no leaks... yet.

[N201MKTurbo]

My old M20F spent most of its life outside here in AZ (very hot). I only filled the tank when they were empty. No leaks.

[aviatoreb]

Old chemical engineers are the best!

-a-

 

I thought old chemical engineers were all dried out - and wrinkled.

[Marauder]

I thought old chemical engineers were all dried out - and wrinkled.

Not with the chemicals they have been exposed to. They're preserved...

Sent from my iPad using Tapatalk

[mike_elliott]

I have heard that heat is the main issue with empty tanks.  ie if the wing sets in the sun empty, it degrades the polymer faster.   I think this is also true for the older polymers.  I think the new ones are more resistant.

 

I am just an old chemical engineer, I did not sleep at a holiday inn express last night......

heat is the enemy of the sealant and for that matter,  the enemy of bladder material also.  Both will have considerably shorter life if the tanks are not kept somewhat full. A hanger certainly helps longevity of both.

Proper patching is important. Just the other day, myself and another launched in a mooney and noticed #4 went cold on the JPI. returned to departure point, and had mx pull the injector where a piece of sealant was found plugging up the thing. Have this work done by a pro who wont let a little piece of tank glue kill you.

[aviatoreb]

Last summer I flew to Boulder, CO KBDU, for and stayed for 5 days - during a heat wave.  I requested explicitly that they refill my tanks right when I arrived.  And I had only 1 hour reserve left in the tanks after a long flight since the last stop.

 

After several 95-100F days...

 

What do you know - when it was time to depart I discovered that they had not refilled my tanks.  Darn!  Dry tanks in high heat - just what I go out of my way to avoid - I knew better than to leave without supervising refilling like I usually do.  I was annoyed.

[carusoam]

Mike, this one might be important for you...

Just getting up from my old guy nap...

Starting with my statistics.

What is the chance of getting tank sealant to show up far down stream in a fuel injector...?

There are so many filter/screens before the injectors.

There is one known source of rubber that when it disintegrates, it Can show up at the injector.

Unfortunately my memory isn't working that strongly today...

Anyone familiar with rubber fuel lines?

I have heard of this before. It may be important to somebody..?

Best regards,

-a-