While the plane sat so many years the mud daubers had gotten into the fuel lines and brake lines buried in the landing gear box. With the skins (
IPC fig 15-23) covering the gear box sides removed these are easy parts to replace so the gear has remained off while I get them done. The mud daubers had made it all the way to the fuel selector valve. Other than cleaning, the selector valve is in very good condition. The only problem was getting the rusty cotter pin out from the handle as well as the screw which broke at the cotter pin hole. After an easy out failed to remove the screw, I carefully drilled it to just short of the tap hole diameter for the 8-32 screw and then used a tap to gently remove the remaining threads of the screw. I need to verify that the valve seals but there were no scratches on the sealing surfaces. The fuel lines might have been cleaned but it seemed better to just fabricate new ones.
I have this cheap tube bender which at least bends the right radius. The edges of the grooves scraped the sides of the tubing so some improvements were needed. I filed a slight radius on the corners of the grooves, then polished each radius with scotch bright and finally with the
Dremel tool and polishing compound. To assure the aluminum tubing moved easily in the aluminum bender I also oiled the groove with a light machine oil, Problem solved.
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The tool looks like it should be just held in your hand and bend the tube. That works fine for 1/4" thin tubing but not for the 3/8" x. 035" tubing used for the fuel lines. To get a tight radius you need to hold the bender against a solid surface to force the tube to stay in the groove while forming the bend.
The result is a bend as well formed as the factory bends.
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To prevent chafing on the fuselage structure the factory slipped lengths of thin rubber tubing over the aluminum before forming the flared ends.
Lowes has a vinyl tubing of the same diameter and thickness which works perfect for this purpose.
This worked fine for the new tubes, but some of the old tubes had been stored away from the mud daubers and didn't need to be replaced. The anti chafing tubing on some of those was cracked. On these old tubes people in the past had used
various clamps, etc. to hold the anti-chafe tubing tight.
Instead I used some heat shrink tubing slipped over the old tube and shrunk to a tight fit. The heat shrink I used was 1-1/4" wide laying flat. It was left over from my hang gliding days in the 70's so I don't remember the diameter.
This size fit nicely over the fittings and shrunk tight. Start shrinking in the middle, work around and then out. They came out great. I think these last 2 pictures are slightly out of focus.
I have this cheap tube bender which at least bends the right radius. The edges of the grooves scraped the sides of the tubing so some improvements were needed. I filed a slight radius on the corners of the grooves, then polished each radius with scotch bright and finally with the Dremel tool and polishing compound. To assure the aluminum tubing moved easily in the aluminum bender I also oiled the groove with a light machine oil, Problem solved.
.
The tool looks like it should be just held in your hand and bend the tube. That works fine for 1/4" thin tubing but not for the 3/8" x. 035" tubing used for the fuel lines. To get a tight radius you need to hold the bender against a solid surface to force the tube to stay in the groove while forming the bend. 
The result is a bend as well formed as the factory bends.
.
.
.
.
.
.
.
To prevent chafing on the fuselage structure the factory slipped lengths of thin rubber tubing over the aluminum before forming the flared ends. Lowes has a vinyl tubing of the same diameter and thickness which works perfect for this purpose.
This worked fine for the new tubes, but some of the old tubes had been stored away from the mud daubers and didn't need to be replaced. The anti chafing tubing on some of those was cracked. On these old tubes people in the past had used various clamps, etc. to hold the anti-chafe tubing tight.
Instead I used some heat shrink tubing slipped over the old tube and shrunk to a tight fit. The heat shrink I used was 1-1/4" wide laying flat. It was left over from my hang gliding days in the 70's so I don't remember the diameter.
This size fit nicely over the fittings and shrunk tight. Start shrinking in the middle, work around and then out. They came out great. I think these last 2 pictures are slightly out of focus.
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