The 116311 family is one of the most widely fitted two-stage thru-flow motor groups Ametek Lamb builds, and the 11631120 is the ball bearing variant on 120 volts. It is a 5.7 in, two-stage motor for dry pickup work in commercial canister vacuums, central vacuum power units and utility machines, and it is bought almost entirely as a replacement part by service technicians and equipment owners rather than as an upgrade.
Thru-flow means the motor is cooled by the working air, which is what keeps a two-stage assembly this compact. It also means the motor is intended for dry pickup only. Ball bearings at both ends, rather than the ball-and-sleeve arrangement used on cheaper motors in the same family, are the reason this variant tends to be specified for machines that run long daily cycles.
Built for
- Commercial canister and upright vacuums on daily janitorial routes
- Central vacuum power units on 120V supply
- Dry pickup utility and shop vacuums
- Service techs replacing a failed 5.7 in two-stage thru-flow motor
Specifications
- Type: Ametek Lamb vacuum motor / blower, thru-flow
- Blower stages: 2
- Body diameter: 5.7 in
- Voltage: 120 V AC, 50/60 Hz, single phase
- Bearings: ball
- Speeds: 1
- Family listings: UL Recognized PRGY2 E47185, CSA class 1611 01 LR31393
A note on published performance figures
Performance numbers circulate freely for the 116311-01 variant of this family, but no source we could verify publishes airflow, sealed vacuum, air watts or amperage for the -20 suffix specifically. Suffix variants in the Lamb range differ in bearing type, bracket style, lead configuration and sometimes winding, so the -01 figures are not repeated here as if they applied to this part. If you need a guaranteed performance figure for a design decision, ask and we will request it from Ametek rather than quote a neighbouring part number.
Fits
No manufacturer machine compatibility list is published for 116311-20, so none is claimed. Confirm part number, body diameter, stage count, height, bracket style and lead configuration against the motor currently in your machine before ordering.
Frequently asked questions
What are the airflow and water lift figures for this motor?
No verified source publishes airflow, sealed vacuum or amperage for the -20 suffix variant. Figures widely quoted online belong to 116311-01, a different variant, so they are not repeated here. Contact us if you need Ametek to confirm a figure.
How is the -20 different from the -01?
Suffix variants within a Lamb family differ in bearing type, bracket style, lead configuration and sometimes winding. This variant is specified with ball bearings. Match the full part number rather than just the 116311 base.
Can I use it for wet pickup?
No. It is a thru-flow motor, so the working air passes over the motor. Wet recovery requires a bypass motor.
Why choose ball bearings over ball and sleeve?
Ball bearings at both ends generally last longer under continuous commercial duty. Ball-and-sleeve motors are less expensive but are usually specified for lighter duty machines.
How long do the brushes last?
Ametek publishes a carbon brush service interval of roughly 500 to 600 operating hours. Brushes worn shorter than 3/16 in should be replaced. A motor will typically accept two brush changes before the armature or bearings become the limiting part, which puts total service life in the 800 to 1200 hour range under preventive maintenance.
Discount Cleaning Products is a United States based dealer for Ametek Lamb vacuum motors and commercial cleaning equipment parts, with live technical support for matching a replacement motor to an existing machine.
