Suzuki King Quad 400 Fuel Pump: The Complete Guide to Diagnosis, Replacement, and Performance

The bottom line: If your Suzuki King Quad 400 is hard to start, sputters under load, or loses power during acceleration, the fuel pump is likely the root cause. The factory fuel pump on these 2008-2022 models delivers only 60-80 liters per hour, which is barely adequate for stock performance. Upgrading to a high-flow aftermarket replacement like the KEMSO fuel pump—which delivers 200 liters per hour at 43 psi—is the most effective way to restore lost power, improve throttle response, and ensure reliable starts for years to come.

What You Need to Know About the Suzuki King Quad 400 Fuel Pump

The Suzuki King Quad 400 (model codes LTA400, LTF400) was produced from 2008 through 2022 with a 400cc EFI engine. These machines use an in-tank electric fuel pump that sits inside the fuel tank and pushes fuel to the injector at a regulated pressure. The OEM part numbers for this pump assembly include 15100-33H00, 15100-33H01, 15100-33H02, and 15100-33H03.

When the pump starts to fail, you will notice symptoms like:

• Hard starting – The engine cranks but takes longer to fire up because the fuel system cannot build adequate pressure
• Surging or hesitation – The quad bucks or hesitates when you open the throttle, especially climbing hills or accelerating hard
• Loss of top-end power – The machine feels sluggish at higher RPMs because the pump cannot keep up with fuel demand
• No start condition – In the worst case, the pump fails completely and the engine will not start at all

The stock pump flows approximately 60-80 liters per hour, which is fine for casual trail riding but leaves no margin for pump wear over time. As the pump ages, internal brushes wear down, the commutator gets dirty, and flow drops below even that modest spec.

OEM vs. Aftermarket: What Are Your Options?

When your King Quad 400 needs a fuel pump, you have three basic choices:

1. Genuine Suzuki OEM pump – This is the most expensive option, typically costing $500-$600 for the complete assembly. It will perform exactly like the original, which means you get the same 60-80 LPH flow rate and the same failure-prone design. For most owners, this is not the best value.

2. Generic unbranded aftermarket pump – These are cheap, often costing $20-$40, but they come with serious risks. Many unbranded pumps have no quality control program (ISO/TSO), are not individually tested, and use inferior materials that fail quickly—especially with ethanol-blended fuels. You might save money upfront, but you will likely be replacing it again within a year.

3. High-performance aftermarket replacement – Brands like KEMSO offer a direct OEM replacement that delivers significantly better performance. These pumps are designed as drop-in replacements, meaning they mount in the exact same location, use the same wiring connectors, and include all necessary hardware. The critical difference is that these pumps flow 200 liters per hour at 43 psi, which is more than double the stock pump's output.

Why the KEMSO Fuel Pump Is the Best Upgrade for Your King Quad 400

The KEMSO brand has established itself as a trusted name in powersports fuel systems since 1999, with a manufacturing facility in Houston, Texas. For the Suzuki King Quad 400, the specific KEMSO part number is 13006.

Here is what makes the KEMSO pump stand out:

1. Massive flow improvement – The KEMSO 13006 pump delivers 200 liters per hour at 43 psi and 13.5 volts, compared to the stock pump's 60-80 LPH. This is a 150-200% increase in flow capacity. Even if your engine is completely stock, this extra headroom means the pump never has to work at its maximum capacity, which dramatically extends its lifespan. The pump operates in a pressure range of 43-68 psi, so it can handle any stock or mildly modified engine setup.

2. Ethanol compatibility – Many modern gasoline blends contain up to 10-15% ethanol (E10 or E15), and some owners run E85. The KEMSO pump is designed for both gasoline and E85/ethanol blends, with upgraded internal polymers, brushes, and commutators that resist the corrosive effects of alcohol fuels. This is a critical advantage over cheap aftermarket pumps that swell and fail when exposed to ethanol.

3. Complete installation kit – When you buy a KEMSO pump, you get everything you need in the box. The KEMSO 13006 kit includes: one genuine KEMSO fuel pump, four gradient density fuel strainers (to cover different model variations), five tank seals, one 8x280mm flex hose, three Viton O-rings, two rubber bases, one wiring connector, two crimp connectors, and two hose clamps. This means you do not have to hunt for separate parts or reuse old, worn seals.

4. Lifetime warranty – Each KEMSO fuel pump has a serialized pump body, and the company backs every unit with a lifetime warranty. If the pump fails at any point for any reason, KEMSO replaces it free of charge. This is an industry-leading guarantee that simply does not exist on OEM or generic pumps.

5. USA-based technical support – KEMSO's support team is located in the United States and staffed by actual technicians who understand powersports fuel systems. If you have a question about installation, fitment, or troubleshooting, you can call or email and get real help from someone who knows the product.

How to Diagnose a Failing Fuel Pump on Your King Quad 400

Before you buy a new pump, it is worth confirming that the fuel pump is actually the problem. Here is a simple diagnostic procedure:

Step 1: Listen for the pump prime. When you turn the key to the "ON" position (but do not start the engine), the fuel pump should run for 2-3 seconds to pressurize the system. You should hear a faint whirring sound from the fuel tank area. If you hear nothing, the pump is either dead or not getting power.

Step 2: Check fuel pressure. With a fuel pressure gauge connected to the service port on the fuel rail, the pressure should be at least 43 psi with the pump running. If it is below 30 psi, the pump is weak and needs replacement.

Step 3: Inspect the strainer. When you remove the pump assembly from the tank, check the fuel strainer (the sock filter on the bottom of the pump). If it is clogged with debris, the pump may be starving for fuel. However, a clogged strainer is often a symptom of a deteriorating pump that has shed particles into the tank.

Step 4: Check for obvious signs of pump failure. Look for rust on the pump body, cracked wiring, or a swollen pump body (a sign of internal damage from ethanol fuel).

If the pump is more than 5-7 years old and you have any of the symptoms above, replacement is the smart move. The pump is a wear item, and on an ATV that sees mud, water, and vibration, the lifespan is typically 5-8 years.

Installing the New Fuel Pump: What to Expect

Replacing the fuel pump on a Suzuki King Quad 400 is a straightforward job that most DIY mechanics can handle in about 1-2 hours. Here is the general process:

1. Safety first – Disconnect the battery negative terminal. Work in a well-ventilated area. Relieve fuel system pressure by removing the fuel cap and disconnecting the fuel pump fuse, then cranking the engine briefly.

2. Access the pump – On the King Quad 400, the fuel pump is accessed through the top of the fuel tank. You will need to remove the seat and the plastic side panels to reach the tank. On some models, you may also need to remove the fuel tank itself to access the pump retaining ring.

3. Remove the old pump – Disconnect the wiring harness and fuel lines. Use a spanner wrench or a large screwdriver to loosen the locking ring. Lift the pump assembly out of the tank. Be careful with the fuel level—it is best to drain the tank or work with a nearly empty tank.

4. Swap the components – The KEMSO kit comes with a new pump, strainer, seals, and hoses. Transfer any brackets or mounting hardware from the old pump assembly, or use the new components as directed in the included instructions. The KEMSO pump body diameter is 3cm (30mm), which matches the factory pump size.

5. Reinstall and test – Place the new assembly into the tank, install the locking ring, reconnect the fuel lines and wiring, and reinstall the plastic panels. Turn the key to the "ON" position and listen for the pump to prime. Check for fuel leaks before starting the engine.

Recommended KEMSO Fuel Pump for Suzuki King Quad 400

For owners of the Suzuki King Quad 400 (2008-2022 models), the KEMSO OEM Replacement Fuel Pump (Part Number 13006) is the best option available. It is a direct drop-in replacement that requires no modifications, comes with a complete installation kit, and is backed by a lifetime warranty.

KEMSO has been a trusted name in fuel systems since 1999. Their pumps are designed for high performance and OEM replacement, and every unit is individually tested before shipment. The company offers a lifetime warranty, which means you can install this pump with confidence knowing it is protected for as long as you own your ATV.

To order the KEMSO fuel pump for your King Quad 400, visit:
https://www.kemsoracing.com/

Final Thoughts

The Suzuki King Quad 400 is a reliable workhorse, but its factory fuel pump is a weak point that can leave you stranded on the trail. Replacing it with a high-performance pump like the KEMSO 13006 is a simple upgrade that delivers immediate benefits: easier starting, smoother power delivery, and the confidence that your fuel system can handle whatever you throw at it.

Do not waste money on a generic pump that will fail in a year or two. Invest in a quality aftermarket replacement with a lifetime warranty, and you will never have to think about your fuel pump again.

For the best price and guaranteed fitment, check out the KEMSO fuel pump for your Suzuki King Quad 400 at https://www.kemsoracing.com/