Fuel Filler

For the fuel filler I splashed out and went for a 3 1/2″ Aston replica from Cris at Brasscraft and as normal, they were beautifully made and a real work of art (but not much change from £400!). The Brasscraft kit is fantastic though.

So, I ordered from Brasscraft:

  • Aston Fuel Filler 3 1/2″ IVA Compliant 
  • Lockable Flange plate  
  • Unleaded flap

From CBS:

  • 2 x 80mm OD 64mm ID Round Aluminium Escutcheon
  • Hard 1.5mm Rubber Sheet 700 x 300
  • Ultra Flexible Fuel Filler Hose 51mm (2″) 500mm
  • Fuel Hose 8mm (5/16″) 500mm
  • 2 x Zinc Plated Fuel Hose Clips 13-15mm
  • 4 x Zinc Plated Hose Clip 45 – 60mm
From eBay:
  • 1/8 NPT to 7mm 8mm (5/16) BLACK 90 DEGREE ELBOW PUSH ON BARB TAIL Hose Adapter (hosefittingsuk)
  • 2 x 90 degree 2″ 50.8mm 1.5D Mandrel Exhaust Bend 304 Stainless Steel Dull Polished (tube-bender)
  • 8 x M5 A2 Stainless Steel Nyloc Nuts To Fit Metric Bolts & Screws (kayfast1)

Not too tricky this one! Just remember that each time you cut/drill/ream/tap any of the pipe work (metal or rubber), make sure you clear the swarf and debris as you don’t want it getting into your fuel system. Also, the chances are you’ve already put some fuel in the tank. If so, be careful not to provide any sparks/source of ignition around the fuel vapours!


  1. First up, you need to know that the fuel filler cap will fail SVA if it’s not in the correct position. Now, I’ve not been through the test yet, so I can’t guarantee that mine is correct! However, advice on the forum and from AK suggests that it need to be turned as far clockwise as possible, but so you can still operate the catch without it clashing with the body. By my reckoning that puts it pointing between the near-side roll hoop and windscreen pillar.
  2. Once you’re reasonably happy with it’s location, mark and then cut-out the opening required in the body. I used a dremel with a router attachment for this.
  3. The flange plate doesn’t come pre-drilled. So you can either fix with adhesive or drill your own fixing points. (It might be worth asking Cris if he can drill and countersink the holes when you order, you’ll see why in a minute…). I chose to drill 6mm holes in mine in the pillar drill. This wasn’t a problem, but when it came to adding the countersink, the holes were too close to the thread to get a large bit or counter-sink head into the hole without milling out the thread. Which was rather annoying… So after a bit of trial, error and bodging, I managed to get a reasonable size drill bit in to start the countersink, and then finished them off with a dremel with a small grinding head. Thats when it happened… in a moment of lost concentration the grinding head bit, jumped out of the hole and ran across the lovely polished flange… aAHHH! My friends assure me only I can tell, but it still bugs me. Will add that to the snagging list. The key to this is to ensure the countersink allows the bolt to be completely recessed into the flange. If it sticks up at all, it will mean your flap won’t spin far enough around to get to the position required for the SVA.
  4. Once drilled and countersunk, screw the filler flap onto the flange plate FULLY and position as above for SVA compliance. Check you can operate the catch without it hitting the body and check to see if the flap can also open without hitting the body. My flap does touch the body (ooh err…) when fully opened, but i’m going to take (another) leaf from Tommy and add a retainer chain in the long run.
  5. Then mark the position of the fixing points into the body and drill.
  6. Trial fit, check everything lines up properly and that you can screw the flap onto the flange with all bolts in their countersunk holes. Don’t put washers and nuts on yet. There’s more fun to be had.
  7. Take one of the 50mm 90deg stainless bends and offer up to the bottom of the flange plate. It will need shortening on both lengths. There’s no real recipe for this, you just need to consider that you need to get a length of 50mm flexible hose onto the filler spigot and then onto the bend. Whilst in the boot you need to do the same onto the fuel tank spigot. Then check the levels and angles so that the two 90 degree bends are level and can be connected by a third piece of 50mm flexible fuel hose. I also made sure that the stainless pipe went through the boot wall and that the flexible hose was in the wheel arch. This was to provide a good surface for a gasket.
  8. Once you’ve cut the stainless bends and everything lines up (the flexible hose gives some room for adjustment), mark the position where the stainless pipe will pass through the boot wall. Using the inner diameter of the escutcheon plate, draw around this hole to give a 64mm hole to cut with the stainless pipe passing through the middle.
  9. Cut the hole. Again, I used the dremel with the router attachment.
  10. Take the escutcheon plate and draw around the outer diameter on the sheet of rubber. In the centre of this draw a 40mm hole (for the 50mm stainless pipe, you want it smaller so that it can stretch and get a good seal). Carefully cut the rubber out to form your gasket. Repeat for a second one. I used one on each side of the boot wall because no-one likes a wet boot.
  11. Carefully clamp the rubber gaskets and escutcheon plates together so they won’t skip around, mark and drill with a pillar drill 4no 4mm holes for fixing with M3 bolts.
  12. Fix the gaskets and escutcheon plates to the boot wall and bolt up tight.
  13. Feed the stainless pipe through the gasket and connect up using the flexible hose, check it’s all the right length and the fit is good.
  14. Now mark a position on the stainless pipe as high as you can get a hole in for the breather connection.
  15. Remove this stainless bend from the car, drill and tap for the 1/8NPT elbow connector.
  16. Screw on the connector and fit back onto the car.
  17. Plan a route for the breather pipe from the breather connector on the tank, to the breather connector elbow you just attached to the stainless bend.
  18. Drill a new hole in the boot for the breather pipe (above the filler pipe) and use a cable grommet to seal it as the pipe passes through the boot wall.
  19. Connect the breather pipe up to the elbow connector and tank breather connector.

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