Aftermarket 7786 Air Grease Pump
This page describes an aftermarket air-operated grease pump that cross-references the Alemite 7786. Alemite is a trademark of its respective owner. This is an aftermarket pump, not manufactured, sponsored, or endorsed by Alemite. 7786 designations are for cross-reference identification only.
This heavy-duty double-acting pneumatic pump is built for high-volume grease transfer and centralized systems. It is commonly used in mining, construction, and manufacturing environments where continuous lubrication demand is high and air supply is available on site.
Double-Acting Operation
The air motor drives a double-acting reciprocating pump tube. Grease moves on both the up and down stroke, which reduces idle time during direction changes. This produces smoother flow with less pulsation than single-acting pumps, making the unit suited to continuous industrial duty and longer grease distribution lines.
Specifications
| Pump ratio | 75:1 |
| Max material pressure | 7,500 psi (517 bar) at 100 psi air |
| Max air pressure | 100 psi (6.9 bar) |
| Delivery rate | 12 lb/min (5.4 kg/min) nominal |
| Air motor | 4 1/4 inch |
| Air inlet | 3/4 inch NPTF |
| Material outlet | 1/2 inch NPTF female x 1/2 inch NPTF male |
| Air consumption | 13 scfm at 100 psi |
| Grease | Up to NLGI 3 |
| Operating temperature | -18 to +60 C |
Container Versions
This aftermarket pump is available in several container configurations for common grease drum setups. The 7786-C version is intended for 120 lb drums. The 7786-A5 version is intended for 400 lb drums. The 7786-MA version uses metric connection sizing for applications outside North America. All versions maintain the same 75:1 ratio and 7,500 psi pressure class. Mounting dimensions and follower plate design differ by container size and cover configuration.
Pressure and Flow
7,500 psi is the maximum material pressure rating, not a constant output. Actual pressure depends on air pressure, grease resistance, hose length, and backpressure in the system. The 12 lb/min delivery rate is nominal, and flow falls as resistance rises. Before ordering, confirm that the compressor can sustain 13 scfm at 100 psi for the duty cycle you expect. For a broader look at pump options, see this grease pump page. If the pump will feed a central bank or manifold, review this heavy equipment lubrication system overview for layout and backpressure considerations.
What to Confirm Before Ordering
Confirm container version first: C for 120 lb drums, A5 for 400 lb drums, or MA for metric connections. Confirm drum size and whether a follower plate or cover is included in the package. Confirm hose and coupler inclusion, because these vary by kit and installation. Confirm that the site air supply can sustain 13 scfm at 100 psi without dropping below required operating pressure. Confirm the grease grade is NLGI 3 or below, since heavier greases reduce flow and increase drive load. For a longer explanation of selection factors, see this complete guide to grease pumps. If your drum size or version is uncommon, contact the team with the model and container details.
Frequently Asked Questions
Does this pump always output 7,500 psi?
No, 7,500 psi is the maximum material pressure rating. Actual pressure depends on air supply and downstream resistance.
What does 75:1 mean?
It means material pressure is roughly 75 times the air pressure at the motor. At 100 psi air, that reaches about 7,500 psi.
Why is double-acting important?
Double-acting means grease moves on both the up and down stroke. This gives smoother flow and less pulsation than single-acting designs.
Is NLGI 3 grease acceptable?
Yes, this pump handles grease up to NLGI 3. Heavier grease will reduce flow and require more air power.
What drum versions are available?
The 7786-C fits 120 lb drums. The 7786-A5 fits 400 lb drums, and the 7786-MA uses metric connections.
Is a follower plate included?
Follower plate inclusion varies by package and container version. Confirm package contents before ordering the pump.
What air supply does the pump need?
It needs about 13 scfm at 100 psi for nominal operation. Confirm the compressor can hold that flow during use.
What flow rate should I expect?
Nominal delivery is 12 lb/min at low resistance. Flow falls as grease resistance and hose length increase.
What is the material outlet size?
The material outlet is 1/2 inch NPTF female by 1/2 inch NPTF male. Confirm your hose end matches that connection.
Who builds this pump, and how do I get a quotation?
IsoHiTech Lubrication Systems, founded in 2023, engineering since 2006, builds and supports every unit. Email inquiry@isohitech.com for specifications and a quotation.
Contact the team with your drum size and version.
