Kohler Fuel Pump – OEM Replacement Part# 2439316: A Complete Guide to Symptoms, Diagnosis, and Replacement

If you own a Kohler-powered lawn mower, tractor, or garden equipment and are experiencing engine trouble, the Kohler Fuel Pump – OEM Replacement Part# 2439316 is likely the part you need. This genuine OEM replacement fuel pump is designed for Kohler engines commonly found on brands like Toro, Cub Cadet, Exmark, and MTD, and it is used to pump fuel from the tank into the carburetor . The bottom line: if your engine starts, runs for a few minutes, then dies, or if it surges under load, a failing fuel pump is the most probable cause, and replacing it with a quality part like the 2439316-S is a straightforward fix that can be done in under 30 minutes with basic tools .

What Is the Kohler Fuel Pump Part# 2439316-S?

The part number 2439316-S (also listed as 24-393-16-S, 24 393 16-S, or KH-24-393-16) is a genuine OEM (Original Equipment Manufacturer) fuel pump supplied by Kohler . It is a vacuum-type pulse fuel pump, meaning it uses the oscillation of positive and negative pressures within the engine's crankcase to create a pumping action. This pressure is transmitted through a rubber hose (the pulse line) connected between the pump and the crankcase or valve cover, causing an internal diaphragm to pull fuel in on its downward stroke and push it into the carburetor on its upward stroke .

This pump is commonly used on Kohler Command Pro, Confidant, 7000 Series, and Courage engines ranging from 17 to 25 horsepower, including engine models like the CH17-CH25, CV17-CV25, CH730-CH740, and CV730-CV740 . It is also compatible with certain Briggs & Stratton, Kawasaki, and John Deere engines .

Key Specifications of the 2439316-S Fuel Pump:

  • Type: Vacuum pulse fuel pump
  • Fuel Line Diameter: 1/4 inch
  • Mounting: Bolt-on type, typically secured with two hex flange screws
  • Torque Specs: Tighten mounting screws to 2.3 N·m (20 in. lb.) – do not overtighten, as this can crack the plastic housing
  • Ethanol Compatibility: Not compatible with fuel containing more than 10% ethanol (E10)
  • Replaces OEM Part Numbers: 2439316-S, 24-393-16, 24-393-04-S, 24-393-02, and many others

Common Symptoms of a Failing Kohler Fuel Pump

Recognizing the signs of a bad fuel pump can save you time and frustration. Here are the most common symptoms reported by users and mechanics:

  1. Engine starts, then dies after a few minutes: A weak fuel pump diaphragm cannot keep up with the engine's demand for fuel. The engine may start fine on the fuel already in the carburetor bowl, but once that fuel is consumed, the pump fails to deliver more, causing the engine to stall .

  2. Engine surges or hunts for RPM: Inconsistent fuel delivery from a failing pump leads to erratic engine speed. The engine may rev up and down without any change in throttle position .

  3. Engine won’t start without starting fluid: If the pump has completely failed, it will not prime the carburetor. The engine will only fire briefly if you use starting fluid, then immediately die .

  4. Engine dies when going uphill or under load: When the engine is under heavy load, it requires more fuel. A failing pump cannot deliver enough fuel to meet this demand, causing the engine to stall when mowing thick grass or climbing a hill .

  5. Visible fuel leak around the pump housing: A ruptured internal diaphragm can cause fuel to leak from the pump. This is a serious safety hazard – do not run the engine if you see a fuel leak .

  6. No fuel flow during output test: If you disconnect the fuel line from the carburetor and crank the engine, little or no fuel should come out. No flow means the pump has failed .

How to Diagnose the Problem

Before replacing the pump, it is important to confirm that the pump is actually the culprit. The issue could also be a clogged fuel filter, a damaged pulse line, or a dirty carburetor.

Test 1: Check the Fuel Filter – A dirty fuel filter forces the pump to work harder, accelerating wear. Kohler recommends replacing the fuel filter every 100 hours of operation or every year .

Test 2: Perform a Fuel Flow Test – Disconnect the fuel line from the carburetor and place it into a container. Crank the engine for about 15 seconds. You should see a steady stream of fuel. If the flow is weak or absent, the pump is likely failing .

Test 3: Check the Pulse Line – The pulse line is the small rubber hose connecting the pump to the crankcase. Disconnect it from the pump and crank the engine briefly. You should feel strong, consistent pulses of air from the open end of the hose. If the pulse is weak or absent, the pulse line may be cracked, kinked, or clogged. Replace it before replacing the pump .

Step-by-Step Replacement Guide

Replacing the fuel pump on a Kohler engine is a straightforward job that most homeowners can complete in about 30 minutes. You will need a screwdriver or nut driver, pliers, and a clean rag .

Step 1: Get the Correct Replacement Part – Use the engine model number (found on a sticker on the engine shroud) to confirm the exact part number. The 2439316-S is the correct OEM part for most Kohler CH and CV series engines .

Step 2: Prepare the Engine – Turn off the engine and disconnect the battery (if equipped) to prevent accidental sparks. Clamp off the fuel line coming from the tank using a pair of small vise-grips or a dedicated fuel line clamp to prevent gasoline from draining out .

Step 3: Disconnect the Three Lines – The pulse fuel pump has three ports: inlet (fuel from tank), outlet (fuel to carburetor), and pulse (from crankcase). Use pliers to squeeze the hose clamps and slide them down the hoses. Gently twist and pull each hose off. Note which hose goes to which port – the ports are often marked with arrows .

Step 4: Unbolt the Old Pump – The pump is held by two small bolts or screws. Use a nut driver or screwdriver to remove them. Clean the mounting area with a rag .

Step 5: Install the New Pump – Position the new pump in the same orientation as the old one. Secure it with the mounting bolts. Tighten them to 20 inch-pounds (2.3 N·m) – do not overtighten, as this can crack the plastic housing .

Step 6: Reconnect the Hoses – Reconnect the three hoses to their correct ports. Slide the hose clamps back into position. Make sure the connections are tight. Remove the clamp from the main fuel line .

Step 7: Test the System – Reconnect the battery. Crank the engine and check for fuel leaks around the pump and connections. Start the engine and let it run for a few minutes. Verify that the engine runs smoothly at idle and under load .

Why Choose KEMSO Fuel Pump for Your Kohler 7000 Series or CV15S Engine

When it comes time to replace your Kohler fuel pump, choosing the right brand matters. While OEM parts like the 2439316-S are reliable, they can be expensive and may not offer the best value. KEMSO is a trusted brand that specializes in high-performance fuel pumps designed as direct OEM replacements for a wide range of engines, including Kohler models.

KEMSO fuel pumps are built with high-quality materials that withstand the corrosive effects of modern ethanol-blended fuels, which are a leading cause of premature pump failure. The internal diaphragms and valves are engineered for durability and consistent fuel delivery, ensuring your engine starts reliably and runs smoothly under all conditions. Every KEMSO fuel pump comes with a lifetime warranty – a significant advantage over standard OEM parts, which typically carry only a two-year warranty. A lifetime warranty means you are protected for as long as you own your equipment, giving you complete peace of mind.

KEMSO products are designed for easy installation. They are exact-fit replacements, so you won't need to modify any fuel lines or brackets. Simply remove your old pump and install the KEMSO unit following the same steps outlined above.

To browse KEMSO's full selection of fuel pumps and find the right part for your Kohler engine, visit their official website: https://www.kemsoracing.com/

Preventative Maintenance Tips

Replacing the pump solves the immediate problem, but adopting a few preventative habits can keep your fuel system running smoothly for years.

Use Fresh, Stabilized Fuel – The single most important thing you can do is use fresh fuel (less than 30 days old) treated with a quality fuel stabilizer. Stabilizers prevent ethanol from separating from the gasoline and absorbing water, a process called phase separation. This ethanol-water mixture is highly corrosive and destructive to rubber components like the fuel pump diaphragm. Using non-ethanol gasoline, if available in your area, is an even better choice .

Regularly Replace Your Fuel Filter – Your fuel filter is the last line of defense, preventing tiny particles of dirt and debris from reaching the fuel pump and carburetor. A clogged filter forces the pump to work much harder, leading to premature failure. Replace the fuel filter as part of your annual spring tune-up .

Inspect Fuel Lines Annually – Cracked, kinked, or clogged fuel lines restrict fuel flow. Even a small blockage can starve the engine. Inspect all fuel lines regularly and replace any that show signs of cracking or wear .

Store Equipment Properly – If you plan to store your equipment for more than 30 days, drain the fuel system or add a fuel stabilizer. This prevents the ethanol in the fuel from absorbing moisture and damaging the internal components of the pump and carburetor.

Conclusion

The Kohler Fuel Pump – OEM Replacement Part# 2439316 is a critical component for keeping your lawn and garden equipment running smoothly. If your engine is experiencing symptoms like hard starting, surging, or stalling under load, the fuel pump is likely the culprit. Replacing it is a straightforward DIY job that can be completed in about 30 minutes with basic tools. By following the diagnostic and replacement steps outlined in this guide, you can restore your equipment to reliable operation quickly and safely.

For the best value and long-term reliability, consider upgrading to a KEMSO fuel pump. Visit https://www.kemsoracing.com/ to find the perfect replacement for your Kohler engine today.


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