David-aviator
Well Known Member
I submit this boo-boo message and perhaps it won't happen to you.
This is mud dabber season, they are here or will be here soon and will clog a fuel vent line or pitot system. That's why we use screens or tube covers.
I've been using simple yellow plastic quarter inch tube caps for some time. Drill a small hole in the leading edge and they work fine. This year I forgot to make that small hole none of the caps.
Three days ago the OAT rose to the mid 80's for the first time this year. I was next to the 8 and notice fuel on the floor under the left drain valve, thinking it was leaking. Wrong. Fuel, a nice stream was flowing from the aft end of the tank. And then I saw the yellow cap on the vent line - darn!!
Opened the fuel cap and there was a rush of air and the leak stopped immediately. But I knew the tank had been compromised. It took 48 hours for the seepage to start, a small blue ring of fuel stain appeared today just outside the first rib along the aft baffle rivet line. Darn, darn, darn!!
Already drained the fuel, began tank removal and ordered a couple tubes of sealant from Vans. It will be repaired but what a dumb thing to do - close the vent line with no weep hole.
PS By way of explanation, if you use the plan vent screens this could not happen. I use a 90° tube intake to add a little head of pressure in the tank to facilitate fuel feed, hence the need to cap the tube openings.
This is mud dabber season, they are here or will be here soon and will clog a fuel vent line or pitot system. That's why we use screens or tube covers.
I've been using simple yellow plastic quarter inch tube caps for some time. Drill a small hole in the leading edge and they work fine. This year I forgot to make that small hole none of the caps.
Three days ago the OAT rose to the mid 80's for the first time this year. I was next to the 8 and notice fuel on the floor under the left drain valve, thinking it was leaking. Wrong. Fuel, a nice stream was flowing from the aft end of the tank. And then I saw the yellow cap on the vent line - darn!!
Opened the fuel cap and there was a rush of air and the leak stopped immediately. But I knew the tank had been compromised. It took 48 hours for the seepage to start, a small blue ring of fuel stain appeared today just outside the first rib along the aft baffle rivet line. Darn, darn, darn!!
Already drained the fuel, began tank removal and ordered a couple tubes of sealant from Vans. It will be repaired but what a dumb thing to do - close the vent line with no weep hole.
PS By way of explanation, if you use the plan vent screens this could not happen. I use a 90° tube intake to add a little head of pressure in the tank to facilitate fuel feed, hence the need to cap the tube openings.
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