Facet Fuel Pump: Your Comprehensive Guide to Universal Fuel Delivery Solutions

Facet fuel pumps are the reliable, often unseen workhorses powering countless engines around the world. Primarily known for their distinctive cylindrical shape and robust construction, Facet fuel pumps (now under the Purolator brand umbrella) provide dependable low-pressure fuel delivery for a vast array of applications, from classic cars and motorcycles to marine vessels, aircraft, agricultural machinery, and industrial equipment. Whether you're restoring a vintage vehicle, building a custom project, or repairing essential machinery, understanding Facet fuel pumps – their types, operation, selection, installation, and maintenance – is key to ensuring consistent engine performance and longevity. Their reputation for durability, simplicity, and effectiveness makes them a go-to choice for professionals and enthusiasts alike when reliable fuel delivery is non-negotiable.

Understanding Facet Fuel Pumps: Core Design and Operation

Unlike the high-pressure electric fuel pumps commonly found inside the fuel tanks of modern fuel-injected vehicles, Facet pumps are primarily designed as low-pressure fuel pumps. They are typically installed outside the fuel tank, often inline with the fuel hose ("in-line electric fuel pump"). Their core operating principle is relatively simple yet robust:

1. The Cube Pump: This is the quintessential Facet design, instantly recognizable by its small, square or cube-shaped metal body (often aluminum or steel). Inside the cube housing resides the core pumping mechanism.

   • Electromagnetic Pulsation: A solenoid coil, energized by the electrical system (usually 12 volts), rapidly pulls and releases a spring-loaded diaphragm.
   • Diaphragm Action: The movement of this diaphragm creates a pulsating suction and pressure cycle.
   • Check Valves: Two one-way check valves (one inlet, one outlet) control the direction of fuel flow. The suction stroke pulls fuel from the tank through the inlet valve. The pressure stroke pushes fuel towards the engine through the outlet valve.
   • Output: The rapid pulsation creates a continuous, low-pressure stream of fuel. Most cube pumps output around 4-7 PSI and flow rates between 15-35 gallons per hour (GPH), ideal for carbureted engines.
   • Self-Priming: A significant advantage of this design is self-priming capability – they can draw fuel up from a tank level below the pump itself, overcoming small siphoning challenges.

2. The Cylindrical Pump (Competition/Solid State): Facet also manufactures cylindrical pumps. While visually different, many operate on a similar electromagnetic solenoid and diaphragm principle, often housed in a larger, cylindrical steel body. They may offer higher flow rates or different mounting options. Some newer cylindrical models incorporate more "solid-state" designs, potentially using brushless DC motor technology driving an impeller or gerotor mechanism. These designs aim for quieter operation but maintain the low-pressure, high-reliability focus. Always refer to the specific model specifications.

Why Choose a Facet Fuel Pump? Key Advantages

Facet pumps have earned their place in diverse industries for compelling reasons:

1. Exceptional Reliability and Durability: Built with robust materials (steel bodies, viton seals common) and a simple, proven design with few moving parts, Facet pumps are renowned for their long service life. They withstand demanding environments, vibration, and harsh operating conditions better than many other low-pressure pump options.
2. Self-Priming Capability: This is arguably their biggest practical advantage. The ability to lift fuel vertically several feet eliminates the need for complex priming procedures or locating the pump below the tank bottom. This is invaluable for installations where the tank is the lowest point or where access is difficult.
3. Wide Compatibility: Facet offers an extensive range of models designed to work effectively with various fuels: gasoline (including alcohol-blended fuels), diesel, kerosene, Jet-A, and even certain types of oil. This versatility is unmatched by many competitors.
4. Proven Performance: Decades of use across automotive, aviation, marine, and industrial sectors attest to their effectiveness. They provide the consistent, low-pressure flow needed for smooth carburetor operation or as reliable lift pumps feeding mechanical injection systems.
5. Mounting Flexibility: Cube pumps are compact and relatively lightweight, making them easy to mount in various orientations (within limits specified by the manufacturer) and in tight spaces using the integral mounting tabs.
6. Cost-Effectiveness: While not always the absolute cheapest option, their durability and longevity make them highly cost-effective over the lifetime of the pump. You pay for reliability.
7. Availability: Facet pumps and their replacement parts are widely available through automotive aftermarket suppliers, marine stores, industrial parts houses, and online retailers.

Common Applications: Where Facet Fuel Pumps Excel

You'll find Facet pumps reliably delivering fuel in countless settings:

1. Vintage and Classic Vehicles: Maintaining authenticity and reliability in carbureted cars, trucks, and motorcycles. Often replacing old, worn-out mechanical pumps or unreliable original electric pumps.
2. Marine Engines: Powering both inboard and outboard carbureted engines, auxiliary generators, and diesel primaries/lift pumps. Their durability handles the marine environment well.
3. Aircraft (Piston Engines): Approved for use in many certified and experimental aircraft, reliably feeding fuel to carbureted or fuel-injected Continental and Lycoming engines. Reliability is paramount here.
4. Agricultural and Industrial Machinery: Tractor auxiliary systems, generators, pumps, welders, and other diesel or gasoline-powered equipment requiring dependable fuel transfer or engine feed.
5. Custom Builds and Kit Cars: Simplifying fuel system design in hot rods, kit cars, sand rails, and other custom automotive projects using carburetors.
6. Emergency and Backup Systems: Providing fuel lift for generators or other critical machinery where pump failure is not an option.
7. Diesel Systems: Acting as low-pressure "lift pumps" to efficiently draw diesel from the tank and feed it into a high-pressure injection pump (common rail, rotary, inline, or distributor types). Their self-priming capability is crucial here to prevent vapor lock and ensure consistent fuel supply to the high-pressure pump, especially after filter changes or tank run-dry situations.

Selecting the Right Facet Fuel Pump: Crucial Factors

Choosing the correct pump model is essential for performance and longevity. Don't assume one size fits all. Consider these critical factors:

1. Fuel Type: This is paramount. Always select a pump specifically designed for your fuel:

   • Gasoline: Look for models rated for gasoline, often noting compatibility with ethanol blends (E10, sometimes E15). Viton seals are generally preferred for modern gasoline.
   • Diesel: Requires specific diesel-compatible models with seals designed to handle diesel fuel. Using a gasoline pump with diesel will lead to premature seal failure.
   • Aviation Gasoline (Avgas) / Jet A / Kerosene: Use only pumps certified or specifically listed for these fuels. Compatibility is critical for safety and performance.
   • Oil: Specific models exist for pumping certain oils.

2. Required Flow Rate (GPH/LPH): Determine your engine's maximum fuel demand. As a rough guide for carbureted gasoline engines: Engine HP multiplied by 0.45-0.5 gives a conservative estimate of GPH flow required. Ensure the pump's free-flow rate significantly exceeds this demand to account for filter restrictions and to maintain adequate pressure. Running a pump near its maximum flow continuously can shorten its lifespan. Selecting a pump rated too low risks fuel starvation under load.

3. Required Pressure (PSI/Bar): Facet pumps are low-pressure devices. Most standard cube pumps deliver 4-7 PSI. This is perfect for carburetors (typically requiring 3-7 PSI). They are not suitable for direct feeding of high-pressure fuel injection systems (which can require 40-80+ PSI). Their primary role in injection systems is as a lift pump feeding the car's primary high-pressure pump or a mechanical injection pump. Always match the pump's pressure specification to your system's requirements. Most Facet pumps are fixed-pressure, though some models offer minor pressure adjustments or have different pressure ratings.

4. Electrical Requirements:

   • Voltage: 12V DC is the standard for automotive/marine applications. 24V DC models are also available for heavy-duty trucks, machinery, and aircraft. Never use a 12V pump on a 24V system without a suitable converter, and vice-versa.
   • Amperage Draw: Ensure your vehicle's electrical system (wiring, fuse, relay) can handle the pump's operational amperage. Check the specifications for "running amps." Undersized wiring can cause voltage drop, poor pump performance, overheating, and fire risk.

5. Pump Designation (Solid State vs. Older Style): Older style "points" solenoid cube pumps have served well for decades. However, newer "Solid State" cube pumps (identified by markings like "S.S.", "POSI-FLO" or "Interrupterless") utilize electronic switching instead of mechanical contact points. Solid State models offer key advantages:

   • Reduced Electrical Noise: Crucial for applications sensitive to radio frequency interference (RFI), like aviation and marine navigation/communication systems.
   • Potentially Quieter Operation: Less "clicking" noise.
   • Reduced Internal Arcing: Leads to potentially longer life and better reliability.

6. Flow Direction: Confirm the pump's inlet and outlet ports match your intended fuel line routing. While many Facets are bidirectional (marked "Any Angle"), double-check the specific model.

7. Environmental Specifications: If the pump will be exposed to extreme temperatures, excessive water spray/splash, or chemicals, verify its housing material (aluminum vs. steel) and seal materials meet the challenge. Most standard pumps are reasonably splash-resistant but are not fully submersible.

8. Mounting: Ensure the pump's physical size and mounting lugs/brackets fit your intended location. Consider vibration isolation pads if mounting to a vibrating surface. Cube pumps should not be mounted with the diaphragm cover facing downward to prevent sediment accumulation and potential valve interference.

9. Reputation and Certifications: Research if the specific model is known for success in your particular application. For aircraft, look for FAA PMA or TSO markings. For marine, UL or CE listings might be relevant.

Installation Best Practices for Facet Fuel Pumps

Proper installation is critical for safety, performance, and pump life. Follow these guidelines:

1. Location, Location, Location:

   • Outside the Tank: Facet pumps are universally designed for external mounting.
   • Near the Tank: Minimize the suction lift distance. While self-priming, shorter suction runs are more efficient.
   • Cool Environment: Avoid mounting near exhaust manifolds, turbochargers, or other excessive heat sources. Heat accelerates fuel vapor formation and pump wear.
   • Dry and Accessible: Protect from direct water immersion and ensure reasonable accessibility for future inspection or replacement.
   • Secure Mounting: Use the pump's integral mounting tabs with suitable screws or bolts. Place vibration-damping pads between the pump and the mounting surface. Ensure minimal stress on the fuel lines.
   • Orientation: While many models advertise "any angle" mounting, follow the manufacturer's specific recommendation (often horizontal diaphragm cover). Avoid mounting the pump vertically with the diaphragm cover facing downwards.

2. Fuel Line Connections:

   • Correct Hose: Use fuel hose rated for submerged or fuel injection applications (e.g., SAE J30R9 or J30R14), even for low pressure. Standard SAE J30R1/R7 carburetor hose is permeable to modern fuel vapors and degrades quickly. Use proper fuel hose clamps, not worm-drive clamps which can cut hoses. Ensure inlet and outlet hose lengths are sufficient to absorb vibrations without kinking or pulling on the pump.
   • Inlet (Suction) Side: The pump draws fuel from the tank. Ensure a robust fuel pickup in the tank avoids air entry, especially during cornering or low-fuel situations. A coarse pre-filter (60-100 micron) is recommended here.
   • Outlet (Pressure) Side: The pump pushes fuel towards the engine. Install the main fuel filter (10-40 micron) here, after the pump, to protect the carburetor or injection pump. Ensure all connections are tight to prevent air leaks or fuel spills.
   • Avoid Kinks and Traps: Ensure fuel lines have smooth bends, avoiding sharp kinks that restrict flow. Never create low spots or loops where vapor can collect. Route lines away from moving parts and heat sources.

3. Electrical Wiring: Safety is paramount. This is a potential ignition source in a fuel system.

   • Fuse Protection: Absolutely mandatory. Install an inline fuse holder as close as practical to the power source (battery or dedicated power distribution panel). Size the fuse according to the pump's maximum rated amperage draw (check specs - usually 5-10A). This protects the wiring from overheating and fire if the pump seizes or shorts.
   • Relay Control: Highly Recommended. Never power the pump directly from an ignition switch. The fuel pump relay is critical:
     • The ignition switch activates the relay's coil (low current).
     • The relay switches the high current needed by the pump, sourced directly from the battery via a fused link.
     • This protects the ignition switch, provides full voltage to the pump, and allows for safety cutouts (like oil pressure or inertia switches - see safety below).
     • Use a relay with an amperage rating exceeding the pump's max draw.
   • Wire Gauge: Use heavy enough wire (e.g., 14 AWG or larger) for both the power feed from the battery to the relay to the pump, and the ground, to minimize voltage drop over the distance. Use automotive-grade stranded copper wire. Secure wiring away from heat and abrasion.
   • Grounding: Provide a secure, clean, metal-to-metal ground connection for the pump's ground terminal. Sand paint/corrosion off the attachment point and use a star washer or proper ring terminal. A bad ground is a common cause of pump failure. Avoid grounding through the pump body unless explicitly designed for it.
   • Inertia Safety Switch (Automotive): Strongly recommended for automotive use. This switch cuts power to the fuel pump in the event of a collision, reducing fire risk. Wire it between the relay output and the pump power terminal.
   • Oil Pressure Safety Switch: Common safety practice (especially in marine). This switch prevents the pump from running unless engine oil pressure is present. It prevents pumping fuel into the engine compartment if the engine stops running unexpectedly. Wire it into the relay control circuit. Can be used alongside an initial prime circuit.

4. Filtration: Essential protection.

   • Pre-Filter (Suction Side): Install a large-pore, high-flow filter (coarse mesh screen or canister filter around 60-100 microns) before the pump inlet. This traps larger debris preventing clogging of the pump's internal valves. Ensure it doesn't restrict flow excessively.
   • Main Filter (Pressure Side): Install a finer fuel filter (10-40 microns is common) after the pump outlet, before the carburetor or injection pump. This catches smaller particles that could clog jets or injectors. Follow filter change intervals religiously.

Troubleshooting Common Facet Fuel Pump Issues

Even reliable pumps can encounter problems. Systematic diagnosis is key:

1. Pump Not Running / No Fuel Flow:

   • Check Power: Verify battery voltage. Check voltage at the pump's power terminal (with connector connected if possible, using a probe or back-pinning - be cautious) when the ignition is on. You should see near battery voltage. If not:
     • Check fuse (visually and with a multimeter for continuity).
     • Check relay (listen for click; swap with a known good relay; test per its pinout).
     • Check inertia switch (reset if tripped; test continuity).
     • Check oil pressure switch (if equipped; bypass temporarily for test).
     • Check ignition switch output feeding relay control.
     • Test all wiring connections for looseness/corrosion.
   • Check Ground: Test continuity from the pump's ground terminal to the battery negative terminal. Clean and tighten the ground connection if resistance is high.
   • Pump Itself: Disconnect fuel lines. Apply battery voltage directly to the pump terminals (observe polarity - often the red wire is +12V, black is ground). A healthy pump should vibrate/click immediately and freely pass air. If it doesn't run, the pump is likely faulty.

2. Weak Flow/Insufficient Pressure:

   • Clogged Filters: This is the most common culprit. Replace both pre-filter and main fuel filter. Inspect for debris.
   • Incorrect Pump Selection: Verify the pump model meets the required pressure and flow specs for your engine.
   • Voltage Drop: Test voltage at the pump terminals while it's running under load. If significantly below battery voltage (e.g., >1V drop), trace back through wiring, connections, relay contacts, and fuse holder for excessive resistance. Upgrade wiring if needed.
   • Air Leak on Suction Side: Any air leak between the fuel tank pickup and the pump inlet will severely reduce flow. Check all suction line connections, fuel pickup tube, and tank seals. Air leaks can be hard to spot visually. Pressurize the line slightly or carefully listen for sucking sounds.
   • Partially Blocked Lines or Tank Vent: Check for kinked hoses, pinched lines, or debris. Ensure the fuel tank vent is clear; a blocked vent creates a vacuum in the tank restricting flow.
   • Worn Pump: Internal wear or valve issues can reduce output. Compare flow rates (disconnect outlet hose, run into a container for a known time) to pump specs. Internal diaphragms or valves can wear over many years.

3. Excessive Noise (Clicking/Buzzing):

   • Normal Operation: Older solenoid "cube" pumps inherently click rhythmically when operating. This is usually normal.
   • Excessive Volume or Vibration: Ensure the pump is securely mounted with proper vibration isolators. Noise transmitted through the chassis is common.
   • Air in Fuel (Cavitation): Air entering the suction side (leaks, low fuel level barely exposing pickup) causes loud rattling/cavitation noise and reduces flow. Inspect the entire suction line meticulously for leaks and ensure adequate fuel supply.
   • Worn Pump Internals: Internal wear can sometimes alter the sound signature. If noise changes significantly and performance suffers, consider replacement.

4. Pump Runs But Engine Stalls/Lacks Power:

   • Vapor Lock: Fuel vaporizing in the line before reaching the carburetor, especially with modern volatile fuels. Caused by excessive under-hood heat. Route fuel lines away from heat sources, consider heat shields on pump/lines, and use high-temperature fuel hose rated for under-hood heat.
   • Restricted Flow: Revisit clogged filters, pinched/kinked lines, failing pump (weak flow).
   • Electrical Intermittency: Check all wiring connections (power, ground, relay sockets) for looseness or corrosion causing the pump to cut in and out. Bad relay contacts can cause this.
   • Fuel Tank Issues: Blocked pickup sock, severely restricted vent, or debris sloshing against the pickup in corners.

5. Fuel Leakage:

   • Severe Failure: A leak from the pump body itself usually indicates a catastrophic failure (cracked housing, severely failed diaphragm). Shut off pump power immediately. Replace the pump.
   • Connection Leaks: Tighten hose clamps. Replace hardened or cracked fuel hose immediately. Ensure the hose barb and hose size are compatible. Use double clamps if needed.
   • Seal Degradation: Internal diaphragm/seals could degrade if incompatible fuel is used over long periods. Leads to seepage, especially noticeable after shutdown.

Maintenance and Longevity: Keeping Your Facet Pump Running Strong

1. Regular Fuel Filter Replacement: This is the single most important maintenance task. Replace pre-filters and main filters according to the pump manufacturer's and engine manufacturer's recommendations, or more frequently if operating in dirty environments or using potentially contaminated fuel. Clogged filters force the pump to work harder, leading to premature wear and failure.
2. Quality Fuel: Use clean fuel from reputable sources. Minimize water in the fuel system, as it promotes corrosion and microbial growth that clogs filters. Use fuel stabilizers for seasonal equipment. Drain old fuel before prolonged storage.
3. Electrical Connection Care: Periodically inspect fuse holders, relays, and all wiring connections for corrosion, tightness, and insulation damage. Clean contacts if necessary.
4. Physical Inspection: Occasionally check the pump's mounting security and look for signs of fuel leaks around the pump body or connections. Check hoses for age (harden/crack around 5-10 years), softening, or abrasion.
5. Avoid Dry Running: While Facet pumps can withstand brief priming cycles without fuel, prolonged operation without fuel for lubrication and cooling causes rapid overheating and damage to internal components (diaphragms, coils). Always ensure fuel is available before prolonged pump operation. If the tank runs dry, address the suction leak or refill promptly.

Safety Considerations: Non-Negotiables

• Fire Hazard: Fuel + Electricity + Heat = Potential for disaster. Never bypass fuses. Ensure all electrical connections are secure, properly gauged, and protected. Route wiring and hoses away from heat and exhaust. Repair leaks immediately. Have a fire extinguisher rated for flammable liquids (Class B) readily available.
• Proper Grounding: A poor ground can cause arcing or overheating at the pump connection, leading to fire. Follow the grounding instructions meticulously.
• Relays and Safety Switches: Do not omit the fuel pump relay or safety switches (inertia, oil pressure). These are critical safety devices designed to prevent fuel pumping during an accident or engine failure.
• Ventilation: Work in well-ventilated areas. Avoid sparks or open flames.
• Static Electricity Discharge: Touch grounded metal before handling fuel system components to dissipate static charge.
• Disconnect Battery: Disconnect the negative battery terminal before working on any part of the fuel system wiring to prevent accidental starting or sparks.
• Tank Precautions: Never weld on or near a fuel tank. Drain the tank completely and properly inert it if repairs requiring heat are needed nearby. Avoid sparks near fuel vapors.

Recognizing When to Replace Your Facet Fuel Pump

Despite their durability, all pumps eventually wear out. Signs it's time for a replacement:

• Complete Failure: Won't run when powered correctly.
• Consistently Weak Flow/Low Pressure: Verified by testing flow rate against specs or poor engine performance persists after ruling out filters/electrical issues.
• Persistent Loud Noise/Cavitation: Not resolved by fixing suction leaks, air intrusion, or mounting.
• Visible Leaks from Pump Body: Indicates internal failure.
• Excessive Amperage Draw: Measured with a multimeter in series with the pump power wire. Significantly higher than the pump's rated draw indicates internal friction or short.
• Age and Prolonged Use: Even seemingly working pumps wear. Consider preventive replacement on critical systems after extended service (e.g., aviation, marine long-range cruising).

Finding the Right Replacement Facet Pump

1. Identify the Old Pump: Look for model numbers, pressure ratings (PSI/Bar), flow ratings (GPH/LPH), voltage rating, and specific designations (e.g., "Solid State", "Interrupterless", "Diesel", "Marine") cast or printed on the pump body or original packaging.
2. Cross-Reference: Use online resources or supplier catalogs to find the direct equivalent Facet pump model number. If that exact model is discontinued, Facet/Purolator often provides a direct replacement/upgrade recommendation (e.g., from older points to solid state). Ensure pressure, flow, voltage, and fuel type compatibility.
3. Supplier Selection: Purchase from reputable automotive parts suppliers, marine distributors, aircraft supply houses (for certified parts), industrial suppliers, or authorized online retailers. Beware of counterfeit or substandard parts.
4. Genuine vs. Aftermarket: While genuine Facet/Purolator pumps offer proven quality and reliability, reputable aftermarket manufacturers do offer compatible options. Research reviews and application fitment carefully if not using a genuine part. For safety-critical applications (aviation, marine), genuine or certified aftermarket is strongly preferred.

Conclusion: The Enduring Value of Facet Fuel Pumps

Facet fuel pumps represent a cornerstone of reliable low-pressure fuel delivery. Their simple, robust electromagnetic diaphragm design, proven over decades in the harshest conditions – from the open sea to vintage car rallies to farm fields – delivers consistent performance where it matters most. The critical self-priming capability solves a fundamental installation challenge. While not suitable for direct high-pressure injection needs, their role as primary feed pumps for carburetors and essential lift pumps for diesel systems is indispensable.

Understanding the different Facet types (cube vs. cylindrical, points vs. solid state), matching the precise pump specifications (fuel type, flow, pressure, voltage) to your application, and adhering to meticulous installation, wiring, and filtration practices are paramount for harnessing their full potential. Proper maintenance, primarily through vigilant fuel filter replacement, ensures these workhorses provide years of trouble-free service. By respecting their requirements and integrating vital safety components like relays and cutoff switches, you leverage the Facet fuel pump's strengths to achieve dependable engine operation and peace of mind across countless demanding applications. When low-pressure, robust, and self-priming fuel delivery is the requirement, a Facet pump remains a top-tier, practical, and proven solution.