Major repair of fuel tank.

Major repair of fuel tank.
1.
Remove all the AN fittings, plugs, strainers, fuel level sensor.
2.
Fabrication of repair part
-
abrade the two flat faces under the tank, on the front side, to get an approximately even
surface. Use filler if required, if the surface is really not even.
Protect with packaging tape (brown) to help de-moulding
Wax
Take a mould of the form (3 layers of 285 g/m² Fibreglass + epoxy resin, + peel ply). This
part will be used to close the hole after the repairs.
3.
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Access hole, repairs inside the tank
Cut the tank widely open to get a good access everywhere.
Inspect inside the tank
Remove drops and run-outs of glue, sealing compound where it does not stick well…
Clean inside carefully with a scotch-brite buffer and MEK (Methyl Ethyl Cetone) or
equivalent. Insist on edges and glue lines.
Rinse carefully with MEK
Inspect carefully the glue lines, in particular on the side edges.
If cracks are found in the glue lines, remove completely the sealant around the crack (4
inches around) and repair with two layers of 4 inches wide 160 g/m² fibreglass (fibres at +/45°) and epoxy resin, and add one layer of peel ply fabric. (no picture available)
4.
Repair part preparation
-
Prepare the moulded parts :
contour them properly (leave a 1-inch-wide gluing surface)
check if they fit well on the tank
sand the inner face and apply two layers of PRC 1750 A2
-
Sand the outside of the tank 4 inches around the repair part.
Clean the dust inside the tank. (MEK)
5.
-
6.
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Sealing the tank
Apply one layer of PR 1750 A2 sealant on the glue lines and critical areas
Leave cure for 48 hours at 20°C minimum
Apply a second layer, everywhere inside the tank
If some areas are not directly visible, check your job with a digital camera
Reinstall the strainer, fittings, venting line, etc… and check they are not obturated with
sealant
Glue the repair part
glue the repair parts with sealant PRC 1750 A2 : IMPORTANT : apply sealant on BOTH
surfaces (repair part, and tank edge) . Hold pressed with tape and weight bags.
Leave cure for 48 hours
7.
Reinforcement layup around repair parts
(no picture available)
-
Remove traces of PR, sand and degrease.
Reinforce the gluing with 2 layers of 160 g/m² fibreglass with fibres orientation at +/- 45°, 4
inches wide, + one peel ply.
Pièces et Matériels nécessaires
RÉPARATION MAJEURE RÉSERVOIR
Parts and materials FUEL TANK MAJOR REPAIR
PIÈCES / PARTS
jeu de 2 pièces de rechange ouvertures de réservoir (D/G)
1 jeu
set of 2 spare parts for fuselage openings
COMPOSITES et Divers
Fibre de verre sergé 160 g/m²
1.5 m. linéaire
glassfibre twill 160g/m²
Tissu de délaminage rouleau 15 cm
5 m. linéaire
Peel-ply roll width 15 cm
Résine époxy SR1700+SD2703
1 kg. mélange
Epoxy resin
Diluant Méthyl-Ethyl-Cétone ou Méthyl-IsoButyl-Cétone
5 L.
Solvent MEK or MIBK
Produit d'étanchéité PRC1750A2 kit 50cc
Sealing compound
MATÉRIEL / tools
tampons à récurer Scotch Brite (rouge)
red Scotch Brite buffers
miroir d'atelier / appareil photo
small mirror
disqueuse pneumatique / Dremel + accessoires
pneumatic tools / dremel and accessories
Papier de verre grain 80-130
sandpaper grit 80-150
Gants latex
Latex gloves
3 pots