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Hi everyone,

I thought I'd take the time post a tip on the nose tire leaks. The nose tire is designed to be used with a tube but Beringer advertises this setup without a tube and designed the wheel in such a way that you cannot put a tube in. A few years ago the nose tires all of sudden started leaking and going flat. I'm sure a number of you have experienced this as well. Something changed in manufacturing the tire and they leak very small amounts out of the tire molding micro vents (the little hairs that come on brand new tires). We found this by submersing the tire in water and noticed very subtle tiny bubbles coming from those mold vent hairs.

We tested a number of tire sealants and found that "Stans No Tube" sealant sealed the tires quit nicely. But with most things there can be too much a good thing. We initially only added 3oz of the Stans No Tube into the tire and it certainly sealed the tire but we noticed on take off that there was a pretty sizable vibration just after the nose wheel left the ground but it would go away after a few seconds. What we found was that the Stans No Tube sealant stays liquid in the tire and will throw the tire out of balance causing the vibration if too much was put in.

We found through iteration that you only need 0.5 to 1oz of Stans No Tube to seal the tire and this isn't enough to cause an out of balance condition. The Maintenance Manual Procedure 14.7.2.11 covers this topic.

I recently got a text from an old customer whom over the years I gained a good friendship. He said that his plane had a vibration no one could solve that occurred right after takeoff and started occurring after his most recent Annual Condition Inspection. I asked him if they replaced the tire or added the sealant lately. He said yes as he had problems with tire going flat. Turns out that the Mechanic that installed the new tire didn't follow procedure in the Maintenance Manual and just followed the back of the Stans No Tube box. I told them to take the wheel off and disassemble the tire to clean it out. Turns out they had something like 6oz of sealant in there. The vibration at 3oz could be pretty bad, twice that was likely very aggressive.

So be on the look out if you have a 10 second or so vibration that shakes the instrument panel badly right after lift off but goes away and that isn't solved by taping the brakes you might check to see if the nose wheel sealant treatment has been applied. If so ask the mechanic if they followed the maintenance manual procedure. It could just be too much sealant which is easy to solve.

Fly safe!