Replacing the Fuel Supply Hose on a 2020 Suzuki KingQuad 750AXi 4x4

Shop parts for a 2020 Suzuki King Quad 750AXi 4X4 ATV.

Preparation carries more weight on this job than wrench skill does. A 2020 KingQuad 750AXi runs electronic fuel injection with a pump inside the tank, and once a fitting is open you want every tool and container already within reach rather than sitting on a shelf across the shop.

Setting Up the Bench

  • Nitrile or rubber gloves, along with eye protection for the moment a fitting releases unexpectedly
  • A shallow drain pan and a sealed container rated for gasoline storage
  • Replacement hose rated for injection pressure in the factory inside diameter, not general-purpose low-pressure line
  • New clamps in the correct style, plus a quick-connect release tool if your machine uses a locking coupler at the tank
  • Line-clamping pliers, which take the place of the petcock this model does not have
  • Metric sockets, a small flat driver, a razor knife, clean rags, and a bright work light

Where you do the work matters as much as what you bring to it. Gasoline vapor is heavier than air and sinks to floor level, where it can travel across a shop and reach a water heater pilot or a sparking motor you never thought about. Work outdoors or immediately inside a wide open overhead door. Shut off pilot lights and space heaters, unplug trickle chargers, keep a dry chemical extinguisher at hand, and seal drained fuel in a proper container rather than leaving an open pan sitting out.

Injection Instead of a Carburetor

The AXi label confirms electronic fuel injection on this 722cc single. Practically speaking, that means three things. No petcock exists beneath the tank, so there is nothing to turn off before you open a joint. An electric pump submerged in the tank holds the supply hose at regulated pressure whenever the key is on, and pressure remains in the line after the engine stops. And the fuel filter is part of that in-tank pump module rather than an accessible inline canister.

That last point separates two different repairs. Replacing the hose cures a cracked, hardened, or weeping line. It does nothing for a restricted filter element, so if the 750 still starves for fuel after a clean install, the in-tank assembly is where to look next.

The Mechanics of Hose Failure

Rubber fuel line has a service life measured in seasons, not miles. The plasticizer compounds that keep it supple migrate out with every heat cycle, and after enough warm-ups and cool-downs the wall turns stiff and slightly glassy. Once flexibility is gone the hose can no longer move with the chassis, and the constant vibration of trail and field work opens hairline cracks at each bend point until one finally passes fuel.

Two outside factors speed this up. Dry storage climates draw residual moisture out of the rubber, hardening hoses noticeably faster than humid air does. Ethanol comes at the problem from inside: E10 pump gas absorbs atmospheric water, and a KingQuad that sits for a long off-season with that blend in the system slowly loses its inner liner. The hose stiffens outward, softens inward, and can appear entirely serviceable while shedding fine material toward the injector.

What a Failing Line Looks and Smells Like

  • A gasoline odor around the tank and seat that persists after shutdown
  • Damp staining or a small puddle beneath the frame after the machine has been parked overnight
  • Fine cracking, chalky surface discoloration, or a length that stays rigid when pinched hard
  • Bogging under load, hesitation on a snapped throttle, or behavior that mimics a nearly empty tank
  • Dirt collected in a damp ring at a fitting, which betrays a slow weep that keeps evaporating

A pressurized system tends to atomize small leaks, so the mist evaporates before it can form a drop. Never dismiss a fuel smell just because the floor underneath is dry.

Getting the Old Line Out

Relieve pressure before anything else. Pull the fuel pump fuse or its relay, crank the engine until it stumbles and quits, switch the key off, and disconnect the battery negative cable. Lift the seat and remove the front fender sections and side panels covering the tank outlet and the hose run to the throttle body. Slide your pan underneath and drape a rag over the first connection you open, because a relieved line still holds fuel that will spill the moment it separates.

Move clamps well back along the hose before disturbing a joint. On a quick-connect, compress both locking tabs evenly and pull straight off in line with the fitting; prying at an angle cracks plastic collars that have grown brittle over several seasons. Twist a stuck hose end gently on the barb to break the varnish bond rather than hauling on it. When it will not release, slit it lengthwise with the razor and peel it away, protecting the fitting underneath.

Map the routing while the old hose is still partly in place. Four-wheel-drive on this KingQuad brings a front differential and extra frame crossmembers, so the line takes a slightly longer path with more clearance points than a two-wheel-drive quad needs. Photograph every clip and guide.

Installation and Verification

Cut the new hose to match the original length precisely. Extra length invites chafing on a frame tube or a sag toward the exhaust. Push each end fully onto its barb until it bottoms against the shoulder, and do the entire assembly dry. Grease, oil, and silicone on a fuel fitting create a leak path for pressurized gasoline under the clamp, so keep them away completely. A hose end dipped in hot water for half a minute goes on easily without any lubricant.

Position fresh clamps just behind the raised bead on each fitting and tighten them evenly, firm enough to seal without biting into the rubber. If your tank end uses a self-locking quick-connect, push it home until it clicks and then pull hard to confirm the latch caught. That fitting requires no clamp. Reinstall the hose into all its original retainers.

Finish with a genuine pressure test. Reinstall the pump fuse, Reconnect the battery, and cycle the key on and off five or six times without cranking so the pump brings the line to pressure while the surrounding area is still spotless. Inspect both joints, wipe them clean, and check again by fingertip. Start the 2020 KingQuad 750AXi and watch the connections at idle, then rev lightly and look once more. After several dry minutes, reinstall the plastics, ride a slow lap of the property, and inspect both fittings one final time.

Related Shopping Categories

Shop Fuel Lines for a 2020 Suzuki King Quad 750AXi 4X4 ATV.

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Shop Petcocks for a 2020 Suzuki King Quad 750AXi 4X4 ATV.

Shop Fuel Filters for a 2020 Suzuki King Quad 750AXi 4X4 ATV.

Shop Fuel Stabilizer for a 2020 Suzuki King Quad 750AXi 4X4 ATV.

Disclaimer: This guide is provided for general informational purposes only and is not intended to replace your ATV's official owner's manual. Always refer to your manufacturer's documentation for model-specific instructions, torque specifications, safety procedures, and maintenance requirements. If you are unsure or inexperienced, consider seeking assistance from a qualified mechanic or technician.