Graco LubePro A4000 Reciprocating Grease and Oil Pump

The Graco LubePro A4000 is a reciprocating air-operated pump for centralised lubrication, built to supply either grease or oil to larger systems than the single-stroke LubePro models. A continuously cycling piston pump gives a 40:1 pressure ratio and builds up to 4000 psi for long supply lines and many lube points.

A 40:1 reciprocating pump for larger lubrication systems

Single-stroke pumps deliver one shot per air pulse. The A4000 is a reciprocating design: it cycles while air is applied and feeds the line, and a vent valve is used to relieve line pressure between cycles so that the metering devices on the system can reset.

Because it can be built as a grease or an oil pump, one pump family covers machinery such as conveyors, presses, mixers and process drives where bearing points are spread over a wide area.

Technical specifications

Choosing the vent valve, reservoir and fluid

The manual lists model groups for a pneumatic vent valve, a series progressive arrangement and an electric vent valve, each in grease and oil versions and with or without low-level detection. Reservoirs are 6 or 12 lb for grease and 12 pints for oil. Pick the vent style to match the metering devices on the system and the controls available on site.

Air supply is limited to 100 psi at the pump. Oil models fill through a strainer in the top cover; grease models use a quick coupler. The pump is for non-corrosive, non-abrasive lubricants only. Installation steps, air-lock procedure, repair and a performance curve are in the manual. The manual also covers grounding, the tubing and hose ratings, which must equal or exceed the pump rating, and a troubleshooting table. Use only non-corrosive, non-abrasive lubricants, and follow the pressure relief procedure in the manual before servicing, because high-pressure fluid can pierce the skin.

Key features of the LubePro A4000

• Continuous reciprocating action: the pump cycles for as long as air is applied, so it can fill long supply lines and feed many metering points in one lubrication event.
• 40:1 pressure ratio: a modest shop air supply is multiplied into high lubricant pressure, enough to push NLGI grease through long tubing runs.
• Grease or oil versions: one pump family can be standardised across a plant, which simplifies spares and training.
• Choice of vent valve: pneumatic, electric or series progressive arrangements suit both injector-type and progressive divider systems.
• Optional low-level detection: a switch signals the controller before the reservoir runs dry and air is drawn into the lines.
• Clear polycarbonate reservoir: the operator can see the lubricant level and condition at a glance.

How the system works

In a typical injector system, a controller or timer opens the air supply to the pump. The pump builds pressure in the supply line until every injector has discharged its set volume to its bearing. The air is then removed and the vent valve releases line pressure back to the reservoir, allowing the injectors to recharge for the next cycle. In a series progressive system the pump feeds a divider block that distributes lubricant to each outlet in turn; a cycle indicator or proximity switch on the divider confirms that the cycle has completed. Matching the vent style to the metering devices is therefore the first selection step.

Installation and maintenance

• Fit a filter, regulator and shut-off valve on the air supply, and set the regulator within the maximum air inlet pressure.
• Use supply tubing and hoses rated at or above the maximum fluid working pressure of the pump.
• Ground the pump and system as described in the manual.
• Prime the pump and purge air from the lines before connecting the lube points.
• Refill grease only through the quick coupler, and oil through the strainer, to keep contaminants out of the reservoir.
• Always carry out the pressure relief procedure before working on the pump or the lines.

Use in Oman and GCC plants

Cement plants, quarries, mines, steel and aggregate conveyors in Oman run dusty, hot and often unattended for long periods, which is where automatic lubrication pays back by keeping contaminants out of bearings. Keep the reservoir shaded where possible, because the stated operating temperature range is limited at the upper end and polycarbonate ages faster in direct sun. Choose a grease consistency that remains pumpable through long lines at the site temperature, and check that the lubricant is non-abrasive and non-corrosive as the manual requires.

What to include in your RFQ

• Part number, or grease/oil, reservoir size, vent valve type and low-level option.
• System type: injectors or series progressive dividers, and the number of lube points.
• Lubricant type and NLGI grade.
• Available air pressure and control voltage.
• Quantity and delivery location.

Documents and quotation

The linked PDF is Graco instruction manual 3A5266G for the LubePro A4000 reciprocating pump. The product page for one part number, 17P750, gives a different reservoir size from the manual, and the manual shows an approximate weight with inconsistent units, so we have not stated either. Please confirm the exact part number, reservoir size, vent valve type, low-level option and fluid before ordering. Send us the part number, quantity and delivery location and we will prepare a quotation; Seven Star LLC supplies from Muscat as an independent supplier. Related lubrication equipment is in our Pumps category, including the Bijur Delimon MultiPort II mobile progressive grease lubricator.