Leaking fuel tanks

[Hondo]

Has anyone found an effective way to seal Mooney fuel tanks?

 

I stripped and resealed my tanks eight years ago.

 

I've been forced to patch leaks seven times since then.

It is like patching a rotten inner tube.

[MooneyMitch]

I suggest taking your Mooney to Advanced Aircraft Services [Mooney Service Center] in Troutdale, Oregon.  Based on my experience, Ed and Greg are experts at sealing tanks. 

[carqwik]

+1 on Advanced...BTDT, no leaks for last three years. I will also add that I thought I had to do a complete reseal but Greg saved me mucho $$ and said only some repair was needed, not a complete job.  Thank you Greg!

[clh]

Sounds like bladders might be best in your case.

[clh]

Sorry to double post, but I cannot figure out how to edit the post.

Another related question is how old are your gear donuts? I was told that if they are old and hard, you will be looking at tank leaks in the not too distant future.

[Bob_Belville]

+1 for O&N bladders. Mine are 16 years old with zero issues.

 

www.onaircraft.com/products-services/mooney-bladders/

[orionflt]

There is a new product out that I am getting ready to try, it is being used in some military applications and the company is working on increasing its GA presence. The sealant can be used over the polysolfied type sealant already used in our tanks orcan be applied to a new or. Stripped surface. The thing I like the best about it is that it maintains it flexibility and will not require resealing for 20 yrs. once I get a chance to evaluate the sealant I will post more info, but I am hoping this is a better alternative to what we have been using.

[Piloto]

+1 for O&N bladders. Mine are 16 years old with zero issues.

 

www.onaircraft.com/products-services/mooney-bladders/

My wet-wing tanks are 31 years old and never leaked. Major cause of sealant failure is heat. Like on any rubber like material like seats and dashboard heat will cause the material to crack and leak. To overcome the heat problem keep your plane in a hangar. If tied down leave the tanks at least half full. Fuel helps to cool down the sealant.

 

Leaks after a strip and reseal are mostly due to the cleaning and application process. These are jobs that are best done by those with experience on the process.

 

Bladders are another option but they take away useful load and can promote wing spar corrosion. These are some of the reasons why you don't see them on new planes. For the airlines bladders was a real headache on the B707. Unlike on modern jets were a can of sealant will fix a leak on all models in the fleet with bladders you needed to stock bladders for each wing section (they are all different) for each different model. And of course the bladder that fails is the one not in stock. Not to mention that putting the bladder back without tearing it was a miracle. To prevent wing spar corrosion it is recommended that the bladder be removed for inspection. Bladders against the wing spar trap condensation/moisture that can lead to corrosion.

 

José  

[Bob_Belville]

My wet-wing tanks are 31 years old and never leaked. Major cause of sealant failure is heat. Like on any rubber like material like seats and dashboard heat will cause the material to crack and leak. To overcome the heat problem keep your plane in a hangar. If tied down leave the tanks at least half full. Fuel helps to cool down the sealant.

 

Leaks after a strip and reseal are mostly due to the cleaning and application process. These are jobs that are best done by those with experience on the process.

 

Bladders are another option but they take away useful load and can promote wing spar corrosion. These are some of the reasons why you don't see them on new planes. For the airlines bladders was a real headache on the B707. Unlike on modern jets were a can of sealant will fix a leak on all models in the fleet with bladders you needed to stock bladders for each wing section (they are all different) for each different model. And of course the bladder that fails is the one not in stock. Not to mention that putting the bladder back without tearing it was a miracle. To prevent wing spar corrosion it is recommended that the bladder be removed for inspection. Bladders against the wing spar trap condensation/moisture that can lead to corrosion.

 

José  

José, thanks for the info. Have there been cases specifically on Mooneys with O&N bladders with spar corrosion? Any SBs or ADs?  (The O&N bladders do add ~30 pounds to the empty weight, not insignificant.)

[rbridges]

José, thanks for the info. Have there been cases specifically on Mooneys with O&N bladders with spar corrosion? Any SBs or ADs?  (The O&N bladders do add ~30 pounds to the empty weight, not insignificant.)

 

there was an AD for the bladders, but that was done years ago.  I can't remember the specifics.

[OR75]

Has anyone found an effective way to seal Mooney fuel tanks?

 

I stripped and resealed my tanks eight years ago.

 

I've been forced to patch leaks seven times since then.

It is like patching a rotten inner tube.

 

Did you had to repatch from year 1 after the reseal ?

If it is the case, I doubt bad doughnuts or heat / sun exposure are the culprits. Just bad workmanship when resealed.

 

Where do you have to patch ? pannels ? rivets ? same location 7 times ?

 

bladders are great but a lot morre $$$ than a reseal and add a bit of weight. They also need to be kepts full which is a good practive even with sealed tank but bladders may be les forgiving on that (from I read).   A properly done reseal should last 20 years+

[Bob_Belville]

 

 

bladders are great but a lot morre $$$ than a reseal and add a bit of weight. They also need to be kepts full which is a good practive even with sealed tank but bladders may be les forgiving on that (from I read).   A properly done reseal should last 20 years+

My friend here with a 67F has more spent resealing than a set of bladders cost. and while I generally fill the tanks, I am not sure that is more of an issue with bladders than with sealed tanks. Not talking dry tanks for months on end... just doubt that 1/2 full bladders in a hanger are at risk. 

[rahawk]

I had Midwest Mooney reseal using their STC, based on a polyurethane process.  Its 12 years old with no issues.  So far so good.

[danb35]

There are two shops I know of that specialize in Mooney tanks: Weep No More in Willman, MN; and Wet Wingologists somewhere in FL.  Two other MSCs seem to do regular work on them, Advanced in Oregon and Midwest Mooney in IL.  Don Maxwell does patches, but I don't believe he does complete re-seals.

 

I had my tanks resealed by Paul Beck at Weep No More, and was very happy with the communication and service, but I can't speak to longevity as it was just done earlier this year.  However, Paul's 5-year warranty includes his travel to your location to fix issues, so it would appear he's quite confident in his work.  With the singular exception of one member here, everything I've seen or heard about Paul's work has been top notch.

 

I've heard generally good things about Wet Wingologists as well, but I felt more comfortable with Paul's mainly chemical removal process than with their mainly mechanical scraping process.  OTOH, they have a 7-year warranty.

 

Midwest Mooney uses a polyurethane sealant instead of the polysulfide material called out by the factory.  They claim additional benefits for their material; I haven't seen anything indicating whether their stuff is good or bad.

[Hondo]

First, thanks for the feedback. I found the "Reseal or bladder" thread and realized this is an ongoing frustrating problem for many.

 

"A properly done reseal should last about 20 years."  I heard that before I resealed mine.  First leak appeared about 18 months later...

I replaced the Lord gear biscuits three years ago. Plane is always hangared.  No carrier landings, but not all are squeakers either.

 

Most of the MSCs I talked to don't want to do tank work.  Dugosh agreed to patch it, but understandably without warranty.

 

Talked to Paul Beck at Weep No More.  He says he has done about 600 Mooneys with good results.  He is booked thru March 2014, so people

are evidently satisfied.  His current quote is 7700 and two/three weeks. 

 

Best quote on installed O&N bladders is 9225.  Some swear by them and others mention fuel leaks at the connectors and water pooling in

the bottom of the bladders if they are not perfectly flat.  According to All American they do not add value on resale.

 

So, I will patch it again and consider Weep No More.

[mike_elliott]

There are two shops I know of that specialize in Mooney tanks: Weep No More in Willman, MN; and Wet Wingologists somewhere in FL.  Two other MSCs seem to do regular work on them, Advanced in Oregon and Midwest Mooney in IL.  Don Maxwell does patches, but I don't believe he does complete re-seals.

 

I had my tanks resealed by Paul Beck at Weep No More, and was very happy with the communication and service, but I can't speak to longevity as it was just done earlier this year.  However, Paul's 5-year warranty includes his travel to your location to fix issues, so it would appear he's quite confident in his work.  With the singular exception of one member here, everything I've seen or heard about Paul's work has been top notch.

 

I've heard generally good things about Wet Wingologists as well, but I felt more comfortable with Paul's mainly chemical removal process than with their mainly mechanical scraping process.  OTOH, they have a 7-year warranty.

 

Midwest Mooney uses a polyurethane sealant instead of the polysulfide material called out by the factory.  They claim additional benefits for their material; I haven't seen anything indicating whether their stuff is good or bad.

 

+1 for Paul Becks workmanship and warranty. I had mine completely stripped and resealed by him back when he worked for Bruce at Willmar. Excellent work. With bladders having a life expectancy of about 15 years, it made more sense to me not to give up the useful load and spend more dollars.  The key to deciding on bladders vs. strip and seal is who is doing the strip and seal. If not done right, you can be doing it over in short order. If done right with today's sealants, there is no reason it wont last 20-30 years. Both options are expensive, one more so than the other.

[rbridges]

+1 for Paul Becks workmanship and warranty. I had mine completely stripped and resealed by him back when he worked for Bruce at Willmar. Excellent work. With bladders having a life expectancy of about 15 years, it made more sense to me not to give up the useful load and spend more dollars.  The key to deciding on bladders vs. strip and seal is who is doing the strip and seal. If not done right, you can be doing it over in short order. If done right with today's sealants, there is no reason it wont last 20-30 years. Both options are expensive, one more so than the other.

 

I emailed Paul, and his responses were prompt and very helpful.  I would do business with him in a heartbeat.  I've told this story before, but I went with bladders.  The local MSC charged roughly what has been quoted, but the expense was a wash since I didn't have to get my plane to Minnesota.  Instead, I had someone fly me to Cole Aviation in Rome, GA.  Since I wasn't instrument rated at the time, it made sense to go with bladders.

 

Also, if I had to bet, bladders that aren't kept empty in the heat will last longer than 15 years.  Someone on this board is flying a mooney with nearly 20 year old bladders.  Of course, a single example doesn't make it fact.  If Wilmar was an hour away, my plane would have a reseal instead of bladders.  To me, it was a coin toss.

[OR75]

 

Talked to Paul Beck at Weep No More.  He says he has done about 600 Mooneys with good results.  He is booked thru March 2014, so people

are evidently satisfied.  His current quote is 7700 and two/three weeks. 

 

Best quote on installed O&N bladders is 9225.  Some swear by them and others mention fuel leaks at the connectors and water pooling in

the bottom of the bladders if they are not perfectly flat.  According to All American they do not add value on resale.

 

To be honest,I would have expected the O&N installed price to be higher than the quote you got. (+$1500 vs reseal)

Is that quote for 64 gallons ?

 

I chose a reseal a few year back but the difference was much higher. I had to patch a pannel once but no probelm since ,

 

The extra weight (~30lbs)  was not a deal breaker for me as I usually fly much lower than gross weight.

 

Installed cost made the difference

[Bob_Belville]

 

  According to All American they do not add value on resale.

 

 

 

Hum, Jimmy Garrison's on line price calculator for an E gives a $1000 premium for O&N bladders. 

www.vintagemooneygroup.com/M20EValuation.html

 

 I really expect my 16 year old bladders to outlast me and my 70 year old bladder.

[jetdriven]

+1 for Paul Becks workmanship and warranty. I had mine completely stripped and resealed by him back when he worked for Bruce at Willmar. Excellent work. With bladders having a life expectancy of about 15 years, it made more sense to me not to give up the useful load and spend more dollars.  The key to deciding on bladders vs. strip and seal is who is doing the strip and seal. If not done right, you can be doing it over in short order. If done right with today's sealants, there is no reason it wont last 20-30 years. Both options are expensive, one more so than the other.

Our bladders are 22 years old and I have no reason to suspect they are failing. Bonanzas have had bladders since 1947 and a few owners have had to replace them, the latest one I heard of was breaking the nipple off where the fuel drain goes in a 1947 model. The bladder itself was fine at 66 years in service.  The other is still the original.

[fantom]

It seems to me that bladder wings people are always attempting to convince themselves, rather than us normal wings people that it's OK the use condoms.

 

It is better than nothing, I guess.....

[Bob_Belville]

I have no direct knowledge of the newer sealants and the several name shops folks swear by but I would be careful to claim that something relatively new will last for longer than it has been in service. Maybe so, maybe no. I suspect there have been quite a few miracle solutions over the last 60 years that are being redone by new and improved stuff by new and improved salesmen. The real world is a lot tougher than the lab.  

[Bob_Belville]

It seems to me that bladder wings people are always attempting to convince themselves, rather than us normal wings people that it's OK the use condoms.

 

It is better than nothing, I guess.....

Hum, I was thinking it was just the reverse...

[mooneyman]

I had a complete strip and polyurethane reseal by Midwest Mooney several years ago. Recently developed a small leak inboard passenger wing. I contacted Matt Lovett at Midwest Mooney. They are no longer doing fuel tank work. He recommended Paul Beck at WeepNoMore, LLC.

 

I emailed Paul and explained the situation. He was quick to respond and very honest that he had not done repair work on tanks with the polyurethane sealant. I made the trip to Wilmar, Mn on 9/13. I arrived late Friday morning. Paul was very professional and knowledgable. He was able to quickly find the leak and apply his fast curing sealant. We filled the tanks the following morning and waited. NO Leak. I was on my way home less than 24 hours after arriving.

 

Paul was great to work with and I recommend him highly for anyone needing fuel tank repairs.

[M016576]

Our bladders are 22 years old and I have no reason to suspect they are failing. Bonanzas have had bladders since 1947 and a few owners have had to replace them, the latest one I heard of was breaking the nipple off where the fuel drain goes in a 1947 model. The bladder itself was fine at 66 years in service.  The other is still the original.

Google "cessna bladder leaks". Lots of threads on that.

Haven't ever heard of a leaking mooney bladder, but most are still relatively new. At 22 years, yours are the oldest I've heard of. The O&N product does look sturdier than the brand C bladders though....