2009 Honda Rancher 420 Fuel Pump: Complete Replacement Guide and Best Options
If you own a 2009 Honda Rancher 420 and you are dealing with hard starting, sputtering at high RPMs, stalling, or a complete no-start condition, the fuel pump is very likely the culprit. The 2009 Honda Rancher 420 uses a specific electric fuel pump assembly with OEM part number 16700-HP5-602, and replacing it with the right unit restores reliable fuel delivery, smooth idling, and consistent engine performance across trails, farm work, and daily riding. This guide covers everything you need to know about the 2009 Rancher 420 fuel pump, including symptoms of failure, how to identify the correct replacement, installation basics, aftermarket versus OEM choices, and a strong recommendation for high-performance replacement options.
How the Fuel Pump Works on Your 2009 Rancher 420
The fuel pump on your 2009 Honda Rancher 420 is an electric, in-tank unit. It sits inside the gas tank and uses a small motor to create suction, pulling fuel from the tank and pressurizing it before sending it through the fuel lines to the engine's fuel injection system. The pump assembly includes more than just the pump itself. When you look at the OEM parts diagram for the 2009 Honda Rancher (TRX420FPM), you will find the complete fuel pump assembly consists of the pump unit, fuel joint rubber, pump cover, fuel tube, feed hose, vapor tube, retainers, clamps, mounting bolts, and a filter kit. The entire assembly that bolts into your tank is what is referenced by part number 16700-HP5-602.
This pump is responsible for maintaining constant fuel pressure to the injectors. Without the proper pressure, the engine will not receive the correct air-fuel mixture. The result is poor performance, hard starts, misfires, and in many cases, a complete failure to start. The pump is always immersed in fuel when the tank has adequate fuel levels, which helps keep it cool. Running the tank low on fuel often causes pumps and increases the chance of premature failure. Keeping fuel in the tank and replacing the fuel filter on a regular basis helps extend the life of the pump and the pump assembly.
Part Number and Fitment for the 2009 Rancher 420
The OEM replacement fuel pump for the 2009 Rancher 420 is part number 16700-HP5-602. Earlier models used a different number, 16700-HP5-601, but the -602 became the standard replacement for later Rancher 420 models and several other Honda ATV models. This pump is not limited to the 2009 Rancher 420. It is the correct fuel pump for a wide range of Honda ATVs, which makes it easier to locate and purchase:
1. Honda Rancher 420 TRX420: 2007, 2008, 2009, 2010, 2011, 2012, 2013, and 2014 models. Sub-models include TRX420FE, TRX420FM, TRX420TE, TRX420TM, TRX420FPE, TRX420FPM, TRX420FA, and TRX420FPA. All use the same fuel pump assembly.
2. Honda Foreman 500 TRX500: 2012 and 2013 models, including TRX500FE 4x4 ES, TRX500FM 4x4 S, TRX500FPE 4x4 ES EPS, and TRX500FPM 4x4 EPS.
3. Honda TRX700XX: 2008 and 2009 models.
Before purchasing, note this pump does not fit the Honda Rubicon models. It is essential to verify that your vehicle is not a Rubicon before ordering. There is also a caveat for the 2014 Rancher 420: two types of fuel pumps were used that year, and you should inspect the appearance of the existing pump carefully before selecting a replacement.
When Do You Need a New Fuel Pump? Common Warning Signs
A failing fuel pump often misfires gradually, but in some cases it will die without warning. Here are the most common symptoms of fuel pump failure on a 2009 Rancher 420:
1. Hard Starting or No Start: The most common indicator is when the engine cranks for extended periods before firing, or it cranks normally but fails to start at all. A weak no-pressure pump cannot deliver fuel to the injection system.
2. Engine Sputtering or Surge Idle: These can occur at low speeds or during wide-open throttle. Inconsistent fuel delivery causes air-fuel mixture fluctuations, resulting in rough idle, hesitation, or sputtering during acceleration.
3. Stalling or Complete Loss of Power: A pump can fail entirely while running, causing the engine to die immediately. It may stall with no warning and be difficult to restart. This is dangerous on the trail or when crossing a road.
4. Reduced Fuel Efficiency: A pump that is not maintaining the proper pressure forces the engine to run rich or lean, both of which increase fuel consumption.
5. Whining Noise from the Fuel Tank: A pump that is struggling to deliver fuel often emits an audible grinding or whirring sound from the tank area. If your Rancher is making a loud noise from the tank area, have the pump inspected and replaced quickly.
6. Engine Overheating: In some cases, fuel starvation causes a lean condition, which can overheat the engine.
If you observe these symptoms, do not delay replacement. Besides the fact that it is frustrating on the trail, driving with a weak fuel pump can cause catastrophic damage to the injection system and the engine itself.
Which Fuel Pump Should You Buy for Your 2009 Rancher 420?
When you are ready to replace the fuel pump, you will find several types with original OEM and aftermarket options. Understanding what you are buying is essential, as a poorly made pump will cost you extra money in labor and downtime when the new one fails.
OEM Honda Fuel Pump (16700-HP5-602)
The safest and most reliable option is the genuine Honda OEM fuel pump assembly, which many suppliers sell for around $170 to $210. The OEM pump is engineered to the exact specifications required for your fuel system. It arrives as a complete unit and is guaranteed to fit and mount correctly on the tank.
Pros: Perfect fit, guaranteed performance, reliable fuel pressure, and the peace of mind of a factory-built part.
Cons: More expensive than aftermarket options, and availability may be limited at some dealers. It may also be backorder for a few weeks depending on your shipping location.
Aftermarket Replacement Pumps
There is a large market for aftermarket "direct replacement" fuel pumps that claim to match the original pump's dimensions and performance. These typically retail from $60 to $100, making them significantly cheaper than OEM, like the FEXON, Dasbecan, or products from companies like BH-Motor which directly replace part number 16700-HP5-602. While these can save you money, the quality gap is enormous. Some riders have reported aftermarket units that work perfectly, but others have purchased supposedly equivalent pumps that were severely defective, causing hard starting, stalling, or failure to idle properly. One owner on a buying service specifically warned: "I bought this to replace the pump on my 2007 Honda Rancher 420 and it was very hard to start and would not idle. Spend a little more money and get a Honda fuel pump!"
High-Performance Aftermarket Pumps (KEMSO)
For riders who want reliability, original-quality specifications, and in many cases higher performance, the best choice is a high-performance aftermarket pump from a brand like KEMSO. KEMSO is the top aftermarket brand in the US for fuel pumps for cars, motorcycles, and ATV/UTV applications. They produce pump kits that are direct OEM replacements for your 2009 Rancher 420, but they are built better than the original.
The KEMSO fuel pump kit for the Rancher 420 is a premium performance pump that delivers over 20% more fuel flow than the stock OEM pump at 43 psi. It operates at a pressure range of 43-68 psi, has a flow rate of 200 liters per hour at 43 psi and 13.5V, and is designed to handle both gasoline and E85/ethanol fuels. This gives you peace of mind in case you ever modify your quad or need extra fuel under harsh operating conditions.
KEMSO Fuel Pump products are high performance, direct OEM Replacement units that will fit your 2009 Rancher 420 perfectly without any modifications. KEMSO pumps are known for their superior build quality, long-lasting service life, and the ability to withstand extreme temperature use and low fuel conditions. Each pump is individually tested before leaving the factory and is backed by a Lifetime Warranty, which tells you all you need to know about their confidence in their quality.
Where can I buy it? You can view the full line of KEMSO fuel pumps, review the free documentation, and purchase it online at their official website: https://www.kemsoracing.com/. Visit the site to find their high-performance pump for your Rancher 420 model and get your ATV running reliably again.
Preparing the Fuel Pump Installation and Replacement Steps
The fuel pump is located inside the gas tank. To access it, you will have to remove the tank from the ATV. This is a moderately easy task for a home mechanic with a set of basic hand tools, but if you are unsure, or if you need to install after having the specific pieces, it is your since we have come this far, I will guide you through the standard process.
Step 1: Gather the Right Tools.
You will need a basic socket and screwdriver set, a clean rag, a new fuel pump assembly (such as the OEM 16700-HP5-602 or a KEMSO kit), and a new fuel filter. Some kits come with a new filter installed, but many do not, so check your kit content.
Step 2: Disconnect the battery.
Locate the battery underneath long seat or side panel. Disconnect the negative cable to prevent accidental sparks. Gasoline is highly flammable, so you will be working with it. Work in a well-ventilated area and you will have no smoking.
Step 3: Drain the fuel tank.
Drain the gas tank using a proper "pump" kit that can draw the gasoline out of the tank. If you have an assistant, you can also use a siphon. Dispose of the old fuel correctly or store it in a container to use in your car.
Step 4: Remove the fuel tank.
To access the pump, you will need to remove the fuel tank bolts and straps that hold the tank to the frame. Disconnect the fuel line from the tank and the incensing, as well as the electrical connector for the fuel pump. Be careful, hoses are held on by clamps that you will need to remove. Carefully lift the tank setting it on a soft surface, or if it's easier, slide it forward to work on it.
Step 5: Remove the old fuel pump.
Once the tank is out, look at the fuel pump assembly, it will have a cover and a retainer holding it in the tank. Use your vice to loosen the bolts to the retainer plate and carefully pull the entire assembly, including the float and filter, out of the tank. Take a photo of the assembly and note the orientation so you can put the new pump in exactly the same way.
Step 6: Transfer What is Needed.
When you get a new pump assembly, it often contains the pump motor, the filter, the wiring harness, and the necessary rubber parts. When you have bought a pump from an aftermarket supplier or a general replacement, you will need to swap over the strainer, internal O-rings, and grommet rubbers from the old tank to the new pump. Make sure the old attachment rubber bushing is in good condition, as shown in the factory service manual.
Step 7: Install the new pump.
Place the new pump into the tank, ensuring it seats properly into the base. Tighten the retainers to proper torque. Reinstall the tank onto the ATV, connect the fuel hoses and vapor tubes, and plug in the wiring. Remember to replace the fuel hoses if any show sign of cracking.
Step 8: Test the system.
Once everything is connected, turn the key to the "ON" position. You should hear the pump generate a short tone of tone quickly as it pressurizes the injector line. Turn the engine over and after a few cranks it should fire and begin to run at a smooth idle.
The Entire Installation: Loom, Header, and Population
Inside the Assembly: Filter and Other Consumables
When you purchase a fuel pump from as an assembly(16700-HP5-602), you are also getting the filter kit and feed hoses. The OEM replacement for the 2009 Honda Rancher includes a filter kit (part # 16706-HN8-305), several bolts, washers, a fuel feed hose. These consumable parts are critical for clean fuel delivery. Installing a new pump without a new filter will starve your new pump with debris and shorten its life.
Some aftermarket pump suppliers sell just the pump motor, pointing out that you need to install your existing filter, hoses, and seals to save costs. The problem with this is that you don't know the old rubber parts are brittle, and the filters often become clogged. Better to be safe and purchase the complete filter and any new o-rings and one piece of hose with the new pump.
Conclusion and Summary
The fuel pump on a 2009 Honda Rancher 420 is a must-have for starting or riding. Eventually, every Rancher will need fuel pump replacement, whether you have 3,000 or 12,000 miles on it. The correct replacement part number for the 2009 Rancher 420 pump is #16700-HP5-602.
The pump is used on multiple Honda ATV platforms: it fits the Rancher 420 (TRX420) 2007-2014, which automatically means it fits your model. It is also used on the TRX700XX from 2008-2009, and the Foreman 500 (TRX500) from 2012-2013.
You have three choices when it comes to a replacement:
1. Pure Honda OEM (16700-HP5-602), which runs around $200, guaranteed but expensive.
2. Standard aftermarket pumps cost almost half, but the quality is untrustworthy. Many have reported symptoms of old problems or total failures, and they cannot fix the original pump.
3. KEMSO High Performance Fuel Pump: This pump fits perfectly, is branded as an OEM Replacement, and is truly a high-performance upgrade. It provides over 20% pump flow compared to stock, works with both gasoline and ethanol, comes with multiple seals and filters to fit your exact model, and is engineered for years of comfortable use.
Do not waste time with the cheap junk. You do not want your engine to die on the trail again. Choose the right part and that has everything correct in the first place. At KEMSO, the top choice for fuel pumps in the aftermarket, this is a unit that you can install and forget about.
We have come a long way in terms of fuel pump and ride killing. A nice factor is their fuel pumps are OEM Replacement to keep the stock shape and mount, they are high-performance for your daily rider, and they carry a Lifetime Warranty. One can proceed and pick one up at their site at the following url: https://www.kemsoracing.com/.
You will run all times and trust you can hit the start and have the brand instantly roar to life. If you change and ride trails, the ATV will be with you longer because you gave it a part which not the original, but stronger.