I have found a nice way to put a vacuum on a tank and seal up a leak. Get one of these:
This creates a nice NO SPARK vacuum so you don't have to worry about fumes blowing up your vacuum cleaner and/or your airplane. Your air compressor will supply the air to make this thing work. I hooked up one of these along with a 0-30 inches of water gauge and a cheap hardware store valve. If you pull about 10-20 inches of vacuum (measured with water not mercury on the gauge) you can put some resin on a leak and this will suck the resin and seal it up. After the resin, cover with flox and unhook the vacuum. Make sure to prep the area by scuffing it up and cleaning it with acetone. I put acetone on the crack while pulling a vacuum to try and clean up inside the crack. Be very careful not to pull too much vacuum or you can collapse the tank. Also, on my old Mooney I used that aeroseal stuff, which is basically lock tight. With that you want about 5 inches of vacuum because it is thin like water and too much vacuum will suck it all the way into the
tank without giving it a chance to seal. (water measure).
I have fixed leaks I had when I got my 360 with this method. Both wings and the header had leaks and now the don't. It works great.
I think the vaccon and gauges with hose and everything should be less than $80 bucks. A nice tool to have lying around.
Matt
From: Christian Meier <lancair@meier.cc>
To: lml@lancaironline.net
Sent: Thursday, January 29, 2009 8:23:54 PM
Subject: [LML] Re: Fuel Tank Testing
Bryan,
In Austria we use following test to check the fueltanks:
Fill the wings completly with water. Seal all openings. Add a tube to the fuel pickup.
This tube should be 1.43 meters high and will also be filled with water. Keep this for a few hours
and check the water level.
1,43m of water = 0,14bar = 4,14inHG Pressure
There is no barometric error.
Christian
Lnc2 / 390
OE-VCM