Ingersoll Rand — Disassembly of the Motor
Repair & overhaul
From a Ingersoll Rand service manual — check it applies to your exact model before use.
Before you start
- The procedure to dislodge the Cylinder requires the use of heat. Take all necessary precautions to prevent burns.
Procedure
- Tap splined shaft of Rotor (22) with a plastic hammer to dislodge Rotor from Front Rotor Bearing (25).
- Lift Motor Housing (26) off Rotor, Rear End Plate (20) and Rear Rotor Bearing (18), which remain together.
- Remove Vanes (23) from Rotor.
- Pull Rear End Plate off Rotor.
- Rap hub end of Rear End Plate on vise jaws to dislodge Rear Rotor Bearing.
- Remove Cylinder Dowel (19).
- For 3940 and 3942 Series: thread four 1/4"-20 socket head cap screws at least 3" (75 mm) long into handle end; strike heads on a table to dislodge Cylinder (21).
- For 3955 Series: thread four 5/16"-18 socket head cap screws at least 3" (75 mm) long into handle end; strike heads on a table to dislodge Cylinder.
- If Cylinder does not drop out, heat alternate sides of Housing until very warm and repeat using thick heavy gloves.
- Rap hub end of Front End Plate on vise jaws to dislodge Front Rotor Bearing.
- Remove two Air Port Gaskets (29) and Air Port Gasket Retainers (28) from Housing.
Tools required
- plastic hammer Amazon
- vise jaws Amazon
- 1/4"-20 socket head cap screws (3940/3942) Amazon
- 5/16"-18 socket head cap screws (3955) Amazon
- thick heavy gloves Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Source: Ingersoll Rand service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.