Table of Contents

Operation of 2500/2800 Series Pneumatic Screwdrivers
Tools Required for Repairing 2500/2800 Series Pneumatic Screwdrivers
Lubrication for 2500/2800 Series Pneumatic Screwdrivers
Lubrication Instructions for Repair and Maintenance
Troubleshooting Guide
2800 Right Angle Drive Disassembly
2800 Right Angle Drive Assembly

Operation of 2500/2800 Series Pneumatic Screwdrivers

The following guidelines are provided to insure safe operation of Standard Pneumatic's 2500/2800 Series Pneumatic Screwdrivers.

  • Always operate, inspect, and maintain any tool in accordance with American National Standards Institute Safety Code for Portable Air Tools (ANSI B1869.1).

  • For safety, top performance, and maximum durability of parts, operate these tools at 90 psig(6.2bar/620 kPa) maximum air pressure at the inlet with 1/4" (6mm) ID air hose.

  • Always turn off and disconnect the air supply before installing, removing, or adjusting any accessory on this tool, or before performing any maintenance or repair.

  • Keep hands, loose clothing, and long hair away from the rotating end of the tool.

  • Anticipate and be alert for sudden changes in motion during start up and operation of any power tool.

  • Standard Pneumatic is not responsible for damage caused by any customer modifications of tools.

  • Do not disassemble if the tool is still in the warranty period. Disassembly by anyone who is not an authorized Standard Pneumatic service technician will void the warranty.

  • Always use clean, dry air. Dust, corrosive fumes, or excessive moisture can damage the motor of an air tool. An air line filter and lubricator are required.

  • Low or fluctuating air pressure causes variations in tool speed and can result in inaccurate torque values.

Tools Required for Repairing 2500/2800 Series Pneumatic Screwdrivers
  • 11/16" open end wrench

  • Crescent wrench - adjustable jaw opening to 1 1/8"

  • Strap wrench

  • Retaining ring pliers (Internal and External)

  • Small hammer

  • Punch (P-3 or similar)

  • 1" Micrometer

  • Small arbor press

  • Pencil with eraser, or 1/4" plastic rod (6"long)

  • Flat plate (glass or other) and Emery cloth

  • Tachometer

  • Container (at least 6" diameter with low walls)

  • Spanner wrench or bearing retainer tool

Lubrication for 2500/2800 Series Pneumatic Screwdrivers

The ideal air supply to our tools can be achieved with our Model 280 Filter-Regulator-Lubricator. The filter element removes contaminating solids, oils and liquids which may be in the compressed air line whether newly installed or not. This filter unit is equipped with a petcock for "dumping" the contaminants without shutting off the air supply.

The regulator controls the air supply to maintain a constant pressure at the tool even though there are changes in the flow demand and or inlet pressure.

When other manufacturers of lubricators are used, it is recommended that the customer check with that particular manufacturer for the proper procedure for setting the lubricator to deliver 1/10 of a drop per minute to the tool. Many lubricators, especially larger units, require high air flow rates for the lubricator to operate properly. Therefore, the manufacturer should also be asked to verify the operation of the lubricator at a 3.6 cfm flow rate for the 2000 series.

Multiple tools on one air system present another problem. When several tools are connected to the same lubricator, it is not possible for the correct amount of lubrication to go to each tool. Since it is highly unlikely that the same number of tools would also be in operation at the same time, the airflow through the lubricator would be a variable; thus the amount of lubrication put into the airflow would also vary. However, with the micro fog type of lubricator, such as our model 280, the oil particle size is such that the oil stays suspended in the air through several "takeoffs" better than with other types of lubricators without wetting out. This results in multiple tools on the same line being better lubricated.

The position of the various tools in the system in relation to the distance away from the lubricator would also cause a variance in the amount of lubrication to each tool. If several tools must be connected to the same lubricator, the same procedure for setting the amount of lubrication on the unit should be used with only one of the tools running. It is assumed that the increased airflow, certain low load or infrequent usage applications it may be possible to operate the tool by manually adding oil on a periodic basis. Inject approximately 2 to 3 drops of tool lubricant to the air intake at the top of each tool.

Lubrication Instructions for Repair and Maintenance

1. Use Standard Pneumatic Tool Lubricant (Part number 100) or a S.A.E. No. 10
nondetergent oil for lubrication the motor.

2. Generously lubricate rotor and blades prior to reassembly of the motor.

3. The spindle (item 23 in Figure 1) should be lightly greased on the gear teeth.

4. Lightly coat all idler gears and spindle gears with Darina AX multifuse grease or equivalent.

Troubleshooting Guide


Possible Cause

Tool will not run or stalls

*Air pressure must be at 90 psig (6.2bar/620kPa)
*Missing or broken rotor blades
*Rotor is tool long
*Burrs on gears
*Toggle valve worn
*Rust or rotor blade debris in cylinder

Loss of power

*Lack of lubrication
*Muffler clogged
*Air pressure must be at 90psig (6.2bar/620kPa)
*Inlet bushing clogged
*Badly worn blades
*Rotor blades installed backwards

Tool stalls before clutch trips

*Clutch adjustment
*Air pressure must be at 90psig (6.2bar/620kPa)
*Rated tool performance vs torque requirement
*Damaged clutch component

Tool will not restart after clutch trips

*Push rod not at correct length
*Burrs on gear
*Badly worn rotor
*Spring on upper clutch spindle broken

Tool runs but no output torque on rt. angle drive

*Broken gear in right angle housing
*Driven gear does not mesh with the output drive gear


NOTE: Whenever a 2500/2800 series tool is to be placed in a vise, use leather or copper covered vise jaws to protect the surface of the part or tool and help prevent distortion. This is especially true of motor housings and threaded portions of the housing. Distortion of the motor housing could result in irreparable damage. The disassembly procedure for the 2800 right angle series is the same as the 2500 except when Right Angle is listed. (Numbers in parentheses refer to numbered parts in the parts drawing)

1. Grasp the tool and remove the clutch housing (34) by turning the housing clockwise (left hand thread). If the clutch housing will not unscrew by hand, then grasp the tool in a padded jaw vise and use a strap wrench to loosen the housing.

2. Remove the clutch from the motor housing assembly, taking special care not to bend the push rod (11) or loose the washer (51) and spring (52) which are located at the end of the clutch.

3. Place an 11/16" open end wrench on the flats of the head assembly, turn clockwise to loosen, and continue turning until the head assembly separates from the motor housing (1). Carefully remove the head/push rod from the motor housing.

4. Remove the motor and drive train assemblies from the motor housing by using a pencil to push them through the housing. Insert the pencil, eraser first, into the external threaded end of the housing. NOTE: Place a shallow container under the motor and gear assembly prior to disassembling. The alignment pin will fall loose when the spindle gear and bearing are removed from the rotor.

5. Remove the motor assembly (items 13 through 23) from the gear assembly. Disassemble the motor by removing the cover plate (13), bearing ring (14), bearing (15), upper end plate (16), and alignment pin (17), from the cylinder (18). Remove the cylinder from the rotor/spindle gear (14,19,20,21,22,23), then remove the rotor blades (22). Remove the spindle gear, bearing, bearing ring, and lower end plate from the rotor. The alignment pin (14) will drop when the spindle gear is removed from the rotor.

6. Check bearings (17) for excessive side play and smooth rotation. Check that the press fit of the bearing and spindle (23,15) is still solid. Inspect the rotor, lower end plate (21), and upper end plate (16) for any scoring or excessive wear. The teeth of the spindle gear (23) should be checked for burrs or excessive wear.

7. Remove the ring gears (24,25) and idler gears (30) from the idler gear plate (26) and driver/pin assembly (27). Inspect all ring gears and idler gears for burrs, chips, and excessive wear. Check bearings (31,32) for wear and smooth rotation. After cleaning idler gears place them on the pins of the idler gear plate, and driver/pin assembly. Rotate each gear making sure it turns smoothly.

8. If the bearing (32) located on the driver/pin assembly requires replacing, remove the retaining ring (33) from the driver/pin assembly (27). Press the driver/pin assembly from the bearing (32). For the idler gear assemblies; press the short spindle gear (28) from the idler gear plate (26) making sure not to loose the alignment pin (29).

9. The head assembly can be disassembled by using the retaining ring pliers to remove the retaining ring (10). Then remove the muffler cap (9) and muffler (8) which should be replaced whenever the tool is in for maintenance. Place a 7/16" open end wrench on the two flats of the inlet fitting assembly (75), then loosen by turning counter clockwise. After the inlet fitting assembly has been removed then the spring (76), toggle valve (77), valve shut off (80), and push rod can be removed. The o-ring (78) and O-ring retainer (79) can be removed by placing a small hook or curved end rod through them, turning it sideways then hooking on the edge and pulling both out. The lever valve (81) can be removed by first lifting the lever as high as it will go or remove it, then grasp the lever valve and remove. To remove the lever pull the studs (71) by placing a pair of wire cutter, with the cutting edges just under the round head. Rock the pliers back and forth along with prying upward until studs are removed. In most cases the studs can be used again. The toggle valve (77) and lever valve (81) should be inspected for excessive wear. If a groove appears on the shaft of the toggle valve (77) then it needs to be replaced.

10. If it is found that the reverse button does not function or the button does not move freely, the tool should be sent back to Standard Pneumatic and Electric Tool Company for evaluation and repair.

11. Clean all parts thoroughly, using cleaning solvent, acetone, or an ultrasonic cleaner with specified soap.

2800 Right Angle Drive Disassembly

1. To disassemble the 2800 right angle drive grasp tool firmly with one hand then turn the clutch housing/angle drive clockwise (left hand threads). If the clutch housing/angle head does not unscrew by hand, then carefully clamp the tool in padded jaw vise and use a crescent wrench (adjustable jaw) placed on the flats where the angle head attaches to loosen the housing.

2. Place the angle head (66) in a padded jaw vise and a crescent (adjustable jaw) wrench on the flats located on the clutch housing (34). Turn the clutch housing clockwise to remove, then grasp the drive gear shaft (62) and remove by pulling it out from the angle head (66). Note: take special care not to loose the spring (52) located inside of the drive gear shaft. One or two shims may possibly be on the drive gear shaft next to the bearing (64), they are there to properly align the clutch housing/angle head with the power unit.

3. Using a spanner wrench, turn the bearing retainer (70) in a clockwise direction to remove. If a spanner wrench is not available then tooling can be made by taking a 1 1/2" wide by 4" long and 1/2" thick piece of aluminum and drilling a 11/32" hole in the center. Then using a #53 drill, machine two holes spaced on centers to a distance of .533 on each side of the 11/32" hole. The two holes should be drilled 3/8" deep and on center line of the larger hole. Then press a dowel pin 1/16" x .500 into each hole.

4. Remove the spindle assembly (69), bearing (64) and driven gear (67). Check the bearings (64) for excessive side play and smooth rotation. Inspect the drive gear (65) and driven gear (67) for excessive wear or cracks in the gear teeth.

5. Clean all parts thoroughly, using cleaning solvent, acetone, or an ultrasonic cleaner/specified soap.


1. If the bearings (33,34) were replaced on the driver/pin or idler gear plate assembly, the re-assembly can be done using an arbor press and parts breakdown as a guide for the orientation of the parts. Take special care not to loose the groove pin (29) when removing spindle gear (28) from the idler gear plate (26).

2. Place the idler gears (30) onto the pins located on the idler plate assembly (26) with the short spindle gear and bearing attached. Insert the assembled gearing into the ring gear (24) making sure the gearing is placed in the recess of the ring gear.

3. Assembly of the driver/pin subassembly is done the same as the idler gear plate assembly except that the ring gear does not fit onto the bearing.

4. Assemble the individual gear trains together, placing them in a v-block or partially opened vise and turn the drive spindle (27) using a 5/32" allen wrench to insure gears rotate freely and smoothly. NOTE: The jaws of the vise should be open enough to just cradle the gear trains.

5. Hold the spindle with the bearing, bearing ring, and lower end plate (23,15,22,21) so that the pin groove is visible. Place alignment pin (74) in the groove on the spindle then slide the rotor over shaft and pin. NOTE: If the bearing needs to be changed, assemble the above items making sure the counter-bore of the lower end plate faces the bearing.

6. Insert the rotor blades item (20) into the slots of rotor with the 30 degree angle facing the center of the rotor.

7. Place cylinder (18) over rotor with the alignment pin hole facing up away from the spindle gear (23). Insert the alignment pin (17) into the hole provided in the cylinder. Place the upper end plate (16), with the recess facing upward, and bearing/bearing ring (14,15) onto shaft of rotor. The alignment pin slips into the small hole, which is in the center of the two large holes in the bearing ring. The bearing ring should be oriented with the notch facing the slot in the cylinder

8. Place the motor and gear trains together. Place a pencil, eraser end first, into the end of the motor housing that has external threads. Then slide the entire assembly into the motor housing (1), inserting the gear train first. The pencil will aid keeping the gear trains intact when sliding the assembly into the motor housing.

9. Using the pencil, slide the motor and gear train assembly back out of the motor housing until the alignment pin is exposed. Then place the head assembly, oriented so that the pin will be inserted in the small hole between the two double drilled holes, onto the top of the motor.

10. Turn the motor housing so that the head assembly faces down. Thread the head into the motor housing by turning it counterclockwise until snug.

11. Hook up the air hose to the tool, then secure the motor housing with the strap wrench or padded vise. Using a 11/16" open end wrench, or crescent (adjustable jaw) wrench, tighten the head assembly, then actuate the tool by first placing a piece of hard bound paper sheet (the pad that is on the bottom of note pads) folded over the end of the tool, then held by wrapping a rubber band around the end of the tool. The folded piece of hard bound paper prevents the push rod extending out so the tool can be actuated with the lever while tightening the head and motor assembly. Tighten the head assembly until the highest rpm is achieved. Verify the rpm by using a tachometer.

12. If required, repeat step 11 until the optimal free speed is achieved. Ideally, the rpm should be as shown below:

Ideal RPM Values
for Model #


1300 RPM


800 RPM


300 RPM


1300 RPM


800 RPM


300 RPM


1300 RPM


800 RPM


300 RPM

2800 Right Angle Drive Assembly

1. If the bearing (64) for the driving gear needs to be replaced then slide new bearing onto drive gear shaft (62), then line up the key (63) with the slot in the gear (65) and press on until fully seated. For replacing new bearing on driven spindle assembly, slide new bearing (64) and driven gear onto spindle assembly (69). Line the hole in the driven gear with the hole in spindle assembly. Press roll pin (68) into hole to secure the driven gear.

2. Insert spindle assembly with bearing and gear attached into angle head (66), making sure the end of spindle is fully placed into brass bushing located inside of angle head, Tighten bearing retainer (70) into angle head by turning it clockwise with spanner wrench.

3. Insert drive gear/shaft with bearing into other side of angle head, turn the input shaft as it is being inserted so gears will properly mesh.

4. If any shims were present when the driven gear shaft was removed, place them onto the shaft then make sure that they seat flush against bearing prior to installing clutch housing. Note: the shim/shims are used to align right angle head with power unit. Insert clutch housing into angle head turn clockwise to tighten. (Note: left hand threads)

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