S-310F Foot Operated Grease Pump

Frequently Asked Questions

What is a foot operated grease pump and how does it differ from a hand operated bucket pump?

A foot operated grease pump uses a foot pedal to drive the piston, freeing both hands for coupler positioning and hose management. Hand-operated bucket pumps require one hand on the lever and one on the coupler, limiting control on difficult fittings. The S-310F also develops 8,700 PSI (double the 4,000 PSI of hand-operated models) because the foot pedal provides a longer lever arm and leg muscles generate more sustained force than arm muscles. Output is 2 g per stroke at this higher pressure.

What pressure does the S-310F foot operated grease pump develop?

The S-310F develops 8,700 PSI (600 bar), which is double the pressure of hand-operated bucket pumps in the same category. This pressure is sufficient to clear fittings that have accumulated hardened grease over extended service intervals. For comparison, most handheld lever action grease guns develop 6,000-12,000 PSI but deliver only 1 g per stroke; the S-310F delivers 2 g per stroke at 8,700 PSI from a 10 kg bulk supply, combining high pressure with bulk capacity.

What is the output per stroke of the S-310F foot operated pump?

The S-310F delivers 2 g per stroke at up to 8,700 PSI. This is a fixed output (unlike the variable 4-9 g per stroke on hand-operated models with 3-position handles). The 2 g delivery is calibrated for precision greasing of individual fittings where controlled, high-pressure delivery matters more than volume. For refilling grease guns or filling large open bearings, the hand-operated S-300 series with its 9 g/stroke high-volume setting is more appropriate.

How does the foot pedal mechanism work for hands-free greasing?

The foot pedal connects to the pump piston via a lever arm that multiplies leg force into hydraulic pressure. Place your foot on the pedal and press down; the piston drives grease through the hose at 8,700 PSI. Release the pedal and the return spring resets the piston for the next stroke. Both hands remain free throughout: one holds the coupler firmly on the grease nipple, the other braces against the machine or guides the hose. The pedal can also be operated by hand when working under low machinery where foot access is restricted.

Why does the S-310F not need a follower plate?

The S-310F uses a wave-action pump design where all moving parts sit submerged within the grease body. Traditional bucket pumps mount the pump above the grease and use a follower plate to push grease up to the inlet. The S-310F inverts this: the pump inlet is always surrounded by grease, so air cannot enter the system regardless of fill level. This eliminates the follower plate (a wear item with a rubber edge that deteriorates over time) and removes the most common cause of bucket pump failure: air lock from a worn or improperly seated follower plate.

How do I prime the S-310F foot operated grease pump for first use?

Fill the bucket with NLGI 1 or 2 grease, tamp firmly with a flat tool to remove air bubbles, then pump the foot pedal 10-15 strokes until grease appears at the coupler tip. Because the pump internals are submerged, priming is faster than on follower-plate designs. After initial priming, the pump maintains prime between uses as long as grease covers the submerged components. If the bucket runs very low (below the pump inlet level), refill and re-prime with 5-10 strokes.

Can I use the S-310F for excavator and heavy equipment greasing?

Yes, excavator and heavy equipment service is the primary application for the S-310F. A typical excavator has 20-50 grease fittings (boom pins, bucket pins, swing bearing, track adjusters, slew ring). The 10 kg bucket provides enough grease for a complete service. The 8,700 PSI pressure clears fittings that have hardened between 250-hour service intervals, and the hands-free pedal lets the operator hold the coupler steady on angled or recessed fittings that are common on excavator undercarriages.

Is the S-310F suitable for single-person tractor maintenance?

Yes, single-person operation is a core design feature of the S-310F. On a tractor with 20-40 grease points (PTO shaft, three-point hitch pins, steering linkage, front axle pivots), one person can hold the coupler with both hands while pumping with their foot. This eliminates the need for a second person to hold the coupler while the first pumps a hand lever. The 10 kg bucket handles multiple tractors per fill during seasonal maintenance windows.

Can I operate the S-310F by hand when working under low machinery?

Yes, the foot pedal can be operated by hand when foot access is restricted. Under low-clearance machinery (truck chassis, conveyor frames, low-mounted equipment), the operator can reach the pedal with one hand while guiding the coupler with the other. The lever arm still provides mechanical advantage when hand-operated, though output pressure may be slightly lower than full foot-pedal force. This dual-mode capability makes the S-310F versatile for both standing and prone working positions.

Why is my foot operated grease pump not dispensing grease?

The most common cause is air in the system, typically from the grease level dropping below the submerged pump inlet. Check the grease level: if the pump internals are exposed above the grease surface, refill the bucket and tamp to remove air. Pump 10-15 strokes to re-prime. If the bucket is full and the pump still does not dispense, check for a clogged coupler nozzle (remove and clean with solvent), a kinked hose, or worn piston seals (inspect the nitrile rubber seals for cracking or deformation).

How do I solve air lock in the S-310F foot operated pump?

Air lock in the S-310F is rare due to the submerged pump design, but can occur if the bucket was filled without tamping. To resolve: open the bucket cover, use a flat tool or gloved hand to tamp the grease firmly around the pump mechanism, pressing out any trapped air pockets. Close the cover and pump 15-20 strokes with the coupler disconnected (pointing into a waste container) until a solid stream of grease exits. If air persists, the grease may have separated during storage; stir or knead the grease to re-homogenise before tamping.

What NLGI grade grease is compatible with the S-310F?

The S-310F is compatible with NLGI 1 and NLGI 2 greases. NLGI 2 (the consistency of peanut butter) is the standard workshop grease and works well at all operating temperatures. NLGI 1 (softer, like tomato paste) flows more easily and is preferred for cold-weather applications or centralised systems. NLGI 3 grease is too firm for this pump's wave-action mechanism and may cause incomplete priming or excessive pedal effort. Lithium, lithium-complex, and calcium sulphonate base greases in NLGI 1-2 are all suitable.

How do I maintain and service the S-310F foot operated pump?

Monthly: inspect the hose for cracks or bulging, check coupler jaws for wear, and verify the foot pedal return spring tension. Every 6 months: remove the pump assembly and inspect the nitrile rubber piston seals for wear or deformation. Replace seals from the repair kit if pressure drops or grease weeps past the piston. Clean the pump chamber with petroleum-based solvent if switching grease types. The submerged design means internal components stay lubricated during use, extending intervals between seal replacements compared with exposed-piston designs.

What is grease injection injury and how do I prevent it with the S-310F?

Grease injection injury occurs when high-pressure grease penetrates the skin and enters underlying tissue, causing severe damage that requires emergency surgery. At 8,700 PSI, the S-310F can inject grease through skin from several centimetres away. Prevention: never point the coupler at any body part, never test for pressure by placing a finger over the outlet, always depressurise by disconnecting the coupler before working on the hose or pump. If injection occurs, seek emergency medical treatment immediately; do not wait for pain or swelling to develop. Tissue necrosis can begin within hours.

What is the difference between foot operated and pneumatic grease pumps?

Foot operated pumps (like the S-310F) require no external power source; pneumatic pumps require a compressed air supply. The S-310F is self-contained and portable, suitable for field service, remote farms, and sites without air infrastructure. Pneumatic pumps deliver continuous output with zero operator effort (the air motor does all the work) but need a compressor within hose reach. For workshops with existing air lines, pneumatic is faster for high-volume work. For portable single-person field use, the S-310F is independent and always ready.

What is the difference between the S-310F and S-310F/Q?

The only difference is the coupler type: S-310F has a standard 4-jaw coupler; S-310F/Q has a quick release grease coupler. The pump mechanism, pressure rating (8,700 PSI), output (2 g/stroke), bucket capacity (10 kg), and hose length (2.2 m) are identical. The quick release coupler snaps onto grease nipples with a push action and releases with a pull, saving 2-3 seconds per fitting compared with the jaw-lock mechanism. For high-volume service rounds (50+ fittings per machine), the time savings of the S-310F/Q add up significantly.