Ingersoll Rand — Assembly of the Impactool
Repair & overhaul · Air Impactool
From a Ingersoll Rand service manual — check it applies to your exact model before use.
Procedure
- Set assembled hammer mechanism onto rotor shaft spline.
- Place Hammer Case Gasket (34) over mechanism and against face of Motor Housing.
- Grease Anvil and top of Hammer Frame.
- Place Hammer Case (39) over mechanism assembly against Gasket.
- Assemble Dead Handle (43) to Dead Handle Bracket (42); insert two Hammer Case Cap Screws (41) and thread into Housing.
- For 3940 and 3942 Series: thread remaining two Cap Screws and tighten all four alternately to 20 and 25 ft-lb (27 and 34 Nm).
- For 3955 Series: thread remaining two Cap Screws and tighten all four alternately to 35 and 40 ft-lb (47 and 54 Nm).
- Install a new Exhaust Silencer (33) in Motor Housing Assembly (26) and install the Exhaust Deflector (32).
Tools required
- torque wrench Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Hammer Case Cap Screws (41), 3940/3942: 20 and 25 ft-lb (27 and 34 Nm)
- Hammer Case Cap Screws (41), 3955: 35 and 40 ft-lb (47 and 54 Nm)
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.