Fuel Tank Components

Types of Fuel Tank Parts

Most gas tank parts fall into six groups: senders, fill parts, caps and vents, mounting hardware, tanks and fuel cell parts. Knowing which group you're shopping keeps you from buying a new sender when the real problem is a blocked vent. Here's what each group covers:

• Fuel sending units that report fuel level to your gauge
• Filler necks, neck plates and fill hoses that route fuel into the tank
• Gas caps, locking caps and vent kits that seal the tank and let it breathe
• Fuel tank straps and mounting hardware that hold the tank in place
• Replacement fuel tanks sized for specific classic trucks
• Fuel cell foam, fill caps and reservoirs for race builds

Some parts solve fitment problems you might not expect. The Tanks Inc. NBO is a 3-1/4 in. 6-bolt flat neck block-off plate that caps an unused filler opening when you relocate the fill. If you're upgrading the whole system, pair these parts with pumps, lines and regulators from our air and fuel delivery parts range.

How to Match a Fuel Sending Unit to Your Gauge

Match the sender's ohm range to the range your gauge expects, then confirm the sender fits your tank depth. A fuel tank sending unit changes resistance as the float moves, and your gauge reads that resistance as fuel level. If the ranges don't match, the gauge reads wrong or pins at one end.

Ohm ratings list the empty value first and the full value second. Common ranges in this category include 0-30 ohm, 0-90 ohm and 240-33 ohm. The Tanks Inc. B1-S2 is a GM-style 0-30 ohm sender with a 3/8 in. pickup, so it handles fuel pickup and level reading in one unit.

Tank depth is the next check. The VDO 226-163 is an adjustable-height sender for tanks 6 in. to 15-3/4 in. deep, reads 240-33 ohm and adds a low-fuel warning contact. Classic Instruments offers adjustable 0-30 ohm senders and the SN38T9, a 0-90 ohm tube-type unit with a 9-1/4 in. tube. Floatless 0-90 ohm senders are another option if you'd rather skip a swinging float arm.

Fuel Filler Necks, Caps and Vent Hoses

Your fuel filler neck, gas cap and vent hose work as one system, so check all three when you have fit or sealing problems. The neck routes fuel into the tank, the cap seals it and the vent lets air in as fuel is drawn out. A problem with any one can cause fuel odor, slow fills or vapor pressure issues.

For restorations, Auto Metal Direct offers fuel filler pipe housings for 1984-1987 Chevrolet/GMC C/K trucks. On custom fills, the Tanks Inc. NE-45 is a 45-degree fuel transfer hose with a 2 in. ID and 12 in. length that joins the neck to the tank inlet.

Cap options include billet fill caps and locking gas cap venting kits. Before you choose, check whether your tank vents through the cap or through a separate vent line. Rubber fill and vent hoses age like any fuel hose, so read our guide to replacing rubber fuel lines to judge when yours are due.

Fuel Tank Straps and Mounting Hardware

Fuel tank straps hold the tank tight against its mounts, so replace them when they're rusted, stretched or cracked. A loose tank shifts under braking and cornering, which strains the filler neck, sender wiring and fuel lines. Worn straps can also let a tank rattle or sit crooked after a restoration.

Match straps to the size and shape of your tank. RCI fuel cell straps are sized for 15-gallon cells, so you can match strap length to the cell you're running. For factory-style tanks, replace the straps and bolts together so the tank sits evenly.

Before you install new straps, check the frame or floor mounting points for rust and thread damage. Tighten the strap bolts evenly side to side, then recheck them after a short drive. If you're relocating the tank or adding a fuel cell, plan strap placement early so it doesn't block the sender, drain or fuel-line routing.

Replacement Fuel Tanks vs Fuel Cell Components

Choose a replacement fuel tank when you want factory fit, and choose fuel cell components when you need a custom layout for racing. A replacement tank bolts into the original mounts and keeps the stock filler and sender locations. The Auto Metal Direct 16-gallon gas tank for short-bed GM trucks is one example.

Fuel cells trade factory fit for flexibility. Options here include a 16-bolt oval fast-fill fuel cell assembly, fuel cell foam that reduces slosh and an 11 x 11 in. fuel reservoir. Browse fuel cell components for foam, caps and fittings, or shop fuel cell parts by part type.

If you're installing a cell, follow our step-by-step fuel cell installation guide. If your cell runs an external pump, our electric fuel pump installation guide covers the job from start to finish. When you're ready, shop the full range of fuel tanks and fuel cells to finish your system.