FUEL TANK

ATV Fuel Pump Maintenance & Diagnostic Guide

Complete manual for all-terrain vehicle fuel system troubleshooting, maintenance, and repair.

Fuel Pump Failure Symptoms & Diagnostic Process

Identification and troubleshooting methods for common ATV/UTV/SSV fuel pump problems.

Safety First: Always work in a well-ventilated area, away from sparks or open flames. Fuel is highly flammable. Disconnect the battery negative terminal before working on electrical components.

Common Symptoms of Fuel Pump Failure:

Starter motor cranks but engine won't start (no fuel delivery)

Engine starts but stalls immediately

Loss of power or poor acceleration under load

Engine surges or stutters

Unusual buzzing or whining noise from fuel tank area

Vehicle stalls after short periods of running

Poor fuel economy

Engine warning light on dashboard (EFI models)

Diagnostic Flowchart (Where to Start Checking):

Step 1: Basic Checks

Confirm sufficient fuel in tank (at least 1/4 full)

Check fuel lines for kinks, cracks, or leaks

Check fuel filter for blockage

Check fuel tank vent for blockage

Check fuel quality (for contamination or water)

Step 2: Electrical System Check

Listen for 2-3 second buzzing sound (initialization) when turning ignition ON

Check fuel pump fuse (usually 15-20A) and relay

Measure voltage at fuel pump connector (should be 12V+ during initialization)

Check ground wire connection

Check ECU control signal to fuel pump

Step 3: Fuel System Pressure Test

Connect fuel pressure gauge to test port (if equipped)

Check pressure against specifications (EFI systems typically 35-50 PSI)

Check pressure hold after pump stops (should hold for minutes)

Test fuel pressure under load

Common Fuel Pump Problems & Solutions:

Problem / Symptom	Probable Cause & Solution
No fuel pump sound when turning ignition ON	Cause: Blown fuse, faulty relay, wiring issue, pump failure Solution: Check fuse/relay first. Measure voltage at pump connector. If no voltage reaches pump, check wiring and ECU.
Pump runs but no pressure or low pressure	Cause: Clogged filter, restricted line, worn pump, clogged pump intake strainer Solution: Replace fuel filter. Check lines for restrictions. Clean or replace pump intake strainer.
Intermittent operation (works sometimes)	Cause: Poor electrical connection, failing pump, thermal protection Solution: Check all connectors for oxidation/corrosion. Test immediately when failure occurs.
Unusually loud buzzing or whining noise	Cause: Pump running dry, worn pump, cavitation Solution: Ensure sufficient fuel. If noise persists, replace pump.
Engine starves for fuel under heavy load	Cause: Insufficient pump output, restricted fuel flow, clogged filter Solution: Test fuel pressure under load. Replace filter and/or pump.

Fuel Pump Maintenance Procedures

Preventive maintenance measures to extend the life of your ATV fuel pump and fuel system.

Pro Tip: Most fuel pump failures are caused by frequently running the tank empty. Fuel helps cool and lubricate the pump. Try to keep the tank at least 1/4 full.

Regular Maintenance Schedule:

Interval / Condition	Maintenance Task
Every 100 hours or annually	Inspect fuel lines for cracks, leaks, or aging. Check all clamps and connections.
Every 200 hours or 2 years	Replace fuel filter (more often if riding in dusty conditions or with questionable fuel quality).
Every 500 hours or 5 years	Consider inspecting fuel pump and cleaning pump intake strainer (if serviceable).
When storing for >3 months	Add fuel stabilizer and run engine for 5 minutes to circulate treated fuel through system.
After water fording or submersion	Immediately check fuel system for water contamination. Drain if necessary.
After every fuel pump replacement	Thoroughly clean fuel tank to remove any contaminants. Replace all related seals.

ATV Fuel Pump Replacement Guide:

Preparation:

Disconnect battery negative cable

Relieve fuel system pressure (EFI models): Loosen fuel cap, disconnect pump connector, crank engine until it stalls

Drain or siphon fuel to safe level (below pump access point)

Prepare tools: socket set, screwdrivers, new pump assembly, new gasket/O-ring

Ensure work area is well-ventilated, no open flames

Removal Steps:

Disconnect fuel lines and electrical connector from pump

Remove pump mounting bolts or locking ring (special tool may be required)

Carefully lift pump assembly out of tank

Note orientation of components and wiring for reassembly

Inspect and clean pump mounting surface

Installation Steps:

Thoroughly clean mounting surface on tank

Install new gasket or O-ring (apply a small amount of petroleum jelly to rubber parts)

Place new pump assembly into tank (ensure correct orientation)

Secure with bolts or locking ring (tighten to specification)

Reconnect fuel lines and electrical connector

Reconnect battery, check for leaks before starting

Turn ignition ON to initialize pump, check for abnormal sounds

Important: Always use OEM or high-quality replacement parts. Cheap aftermarket fuel pumps often have shorter lifespans. When replacing a failed pump, always thoroughly clean the fuel tank to remove all contaminants.

Fuel System Cleaning & Care:

Periodically use reputable brand fuel system cleaner

Avoid low-quality fuel; refuel at reputable stations

Before long-term storage, fill system and add stabilizer

Regularly check fuel cap seal to prevent moisture ingress

After water fording, check fuel filter bowl for water

Fuel Pump Testing Methods

How to properly test your ATV fuel pump using basic tools.

Typical Fuel Pump Technical Parameters:

Operating Voltage: 12V DC (Normal Range: 10.5-14.5V)

Operating Current: 4-8A (depends on specific model)

Resistance Value: 1-5 Ohms (refer to service manual)

Flow Rate: 0.5-1.2 liters/minute

Electrical Tests (Multimeter Required):

Resistance Test (Bench Test):

Remove pump from vehicle

Set multimeter to Ohms (Ω)

Measure resistance between pump terminals

Normal range: 1-5 Ohms (refer to specific service manual)

∞ (Infinite) resistance = Open circuit (pump failed)

0-0.5 Ohms = Possible short circuit (pump failed)

Voltage Test (In-Vehicle Test):

Insert multimeter probes into fuel pump electrical connector (set to DC Voltage)

Turn ignition ON (do not start engine)

Should show battery voltage (12V+) for 2-3 seconds during initialization

If no voltage: Check fuse, relay, wiring, ECU signal

Current Test:

Connect multimeter in series with pump power wire (set to DC Current)

Normal current: 4-8 Amps (depends on pump size)

High current (>10A) indicates pump working too hard (clogged or failing)

Low current (<3A) may indicate weak pump or electrical issue

Mechanical / Flow Tests:

Flow Test:

Disconnect fuel line at fuel rail or carburetor

Place hose end into approved container

Turn ignition ON (or jumper pump relay) to activate pump

Measure fuel output over 15 seconds

Normal value: 0.5-1.0 liters/minute (refer to service manual)

Weak flow indicates clogged filter, restricted line, or weak pump

Pressure Test (EFI System):

Connect fuel pressure gauge to test port on fuel rail

Turn ignition ON to initialize system

Record pressure value (Most ATVs: 35-50 PSI)

Start engine – pressure should remain steady

Pinch return line (if equipped) – pressure should rise significantly

Turn engine off – pressure should hold for minutes

Testing Tip: Always compare test results against manufacturer specifications. Fuel pump performance can vary with temperature and voltage. For accurate results, ensure battery is well charged (at least 12.6V) during testing.

Troubleshooting Quick Reference:

Test Result	Interpretation
No voltage at pump connector	Check fuse, relay, wiring, ignition switch, ECU
Voltage present but pump doesn't run	Pump failed, bad ground, seized pump
Pump runs but no/low pressure	Clogged filter/strainer, restricted line, weak pump, faulty pressure regulator
Pressure drops quickly after shutdown	Leaking injector, failed internal check valve, external leak
Pressure too high	Faulty pressure regulator, restricted return line

If you are unable to find the corresponding parts for the catalog, please contact us.

Image/No	Product	Price
02	Fuel Tank Front Rubber Sleeve - Model: MICF9010-120006 - Stock：In Stock	US$0.90
05	Fuel Pump - Model: MICF901F-150900-10000 - Stock：In Stock	US$37.50
08	EFI Fuel Filter Rubber Sleeve - Model: MICF6090-120221 - Stock：In Stock	US$1.13
12	Quick Joint - Model: MICF6090-120210-1000 - Stock：In Stock	US$2.50
16	Fuel Tank Cap - Model: MICF9CR6-120300 - Stock：In Stock	US$9.27
17	Fuel Tank Rear Cushion Sleeve - Model: MICF9010-120007 - Stock：In Stock	US$1.80
8+9	Fuel Filter - Model: MICF6090-120220 - Stock：In Stock	US$10.25