Mooney Fuel Tanks

[mauricefrompolo]

I am in the process of looking to buy a Mooney model "B" through "F" and am confused about the weeping fuel tanks. What I read about O&N bladders is that they are only warranted for 5 years at a cost of somewhere around 7 grand installed. It looks to me like a reseal, if done properly, will outlast that. My question is, "which is best, bladders or reseal"? Or, should there be any concern?

 

[Ted]

Your car may have a 3 year 36,000 mile warranty, but one generally hopes it lasts longer.

On the M20F I used to fly, we went for the O&N bladders when the wings were leaking. The thought there was that it did cost a lot more up front, but it would also hopefully last a lot longer. Additionally, we went for the long-range tanks, which added another 6-10 gallons or so, a very nice feature on longer trips. Total installed was about $11k. I really don't know which one was better, all I know is what we did. It worked well.

 

[Lance F]

First of all make sure the tanks aren't leaking in the first place in your prebuy. Then you won't have to spend anything.
Second, I wouldn't evaluate one or the other as being "better." The fact is that both systems are working on many planes.
A properly resealed tank will last just as long as the bladder warranty. One for one you lose volume and add weight with the bladders. As Ted points out, though, additional bladders can be added to some models. That helps the range but not the weight issue, and it's pretty expensive.
Finally, some leaks can be effectively patched at a small fraction of the cost of either a total reseal or bladders.

 

[Mooneymike]

My tanks have never been resealed. If they leak I will reseal them myself. I spent 3 years doing tank reseals on SA227 Metroliners, so I am comfortable working with sealers. It really is a very easy but time consuming process. If you are at all inclined to do your own work you can reseal the tanks, working with a certified mechanic for about $300 in material. Figure on about 40-50 hours of actual labor.Lack of cleanliness is the number one reason for falure. If you would not eat off the aluminium before applying the sealer its not clean enough. The second most common cause is temperature.

 

[Walt]

Maurice,
For the last 40 years I have owned airplanes (mostly Mooneys) with integral tanks. I would (have) stick with reseals not bladders. If you buy a Mooney remember the name Willmar Air Service. They are know what they are doing at repairing integral tanks.
Walt

 

[mauricefrompolo]

Thanks guys,

I can tell by the postings that it all boils down to if it ain't broke don't mess with it and if it is broke there are highly qualified people to fix it.

I am looking forward to our Mooney purchase in the next few weeks and hours of enjoyable flying time.

Thanks again,
Maurice