This is the motor a service tech reaches for when a commercial canister, wet-dry vac, or car-wash vacuum has gone quiet and the diagnosis points past the brushes. It is an Ametek Lamb 116758-13, a 120 volt single-phase two-stage bypass motor-blower with a 5.7 inch body and Acustek peripheral discharge, and it supersedes the earlier 116758-11 and 116758-29 in the same family.
Bypass is the detail that matters most here. In a bypass design a separate fan pushes clean air across the armature, so the motor is not depending on the dirty working airstream for cooling. That is precisely the failure path that kills thru-flow motors: as the bag or filter loads, airflow drops, cooling collapses, and the windings cook. A bypass motor keeps running cool through a loaded bag. It also means clean, dry air only, so this is not a wet-through-motor design.
Two stages favor airflow over top-end lift, which suits general pickup and vac boxes on scrubbers. For deep water extraction the three-stage sibling is the better match. Confirm the number on your motor tag before ordering, since the 5.7 inch family includes both peripheral and tangential discharge versions.
Built for
- Direct motor replacement in a dead commercial canister or wet-dry vacuum
- Car-wash and detail-shop vacuum rebuilds
- Central vacuum power-unit service where the original Lamb motor has worn out
- Vac boxes on floor scrubbers and sweepers badged Tennant, NSS or Windsor
- OEM and equipment-builder applications needing a proven 5.7 inch bypass blower
Specifications
- Type: 2-stage bypass motor-blower, peripheral (Acustek) discharge
- Voltage: 120 V single phase, 50/60 Hz, single speed
- Current draw: approximately 9 A
- Maximum airflow: 103 CFM
- Maximum air watts: 293 W
- Sealed vacuum: 91.5 inches of water
- Speed: 23,436 RPM
- Diameter: 5.7 inch (145 mm); overall height 6-1/2 inch; overall length 6-5/8 inch
- Bearings: ball; insulation class A; average motor life 500 hours
- Enclosure: open drip-proof, no thermal protection, intermittent duty
- Mounting: all-angle lug mount with thermoset brackets; maximum ambient 40 C
- Approvals: CSA LR31393, UL E47185; weight approximately 5 lb
- OEM cross-reference: Tennant 130406
Frequently asked questions
Will this replace my OEM part number?
It is the current Ametek 116758-13 and supersedes 116758-11 and 116758-29. It is also the documented replacement for Tennant 130406. Many machines badged NSS, Nilfisk, Windsor or Minuteman use Lamb motors, but badge alone is not enough. Read the number stamped on the motor tag and match it, and our staff will confirm it for you.
Can it pick up water?
No. A bypass motor is designed for clean, dry cooling air and the working airstream does not pass through the motor. Wet pickup requires a machine built for it, with the motor protected from the recovery airstream.
Is two-stage enough suction?
For general pickup, canister vacuums and most vac-box applications, yes. Two stages are biased toward airflow, which is what moves debris. Three stages trade some airflow for higher sealed lift and are the choice for deep water extraction.
Why did my last motor only last a couple of years?
The most common causes are worn carbon brushes that were never inspected, and restricted airflow from a clogged bag or filter starving the motor of cooling. Before replacing a motor, pull it and look at the brushes and commutator, since brushes and bearings cost a fraction of a motor.
Do I need a whole motor or just brushes?
If the motor runs weak, sparks, or cuts in and out, check the brushes first. Replace them when the carbon is worn to about 3/16 inch. A motor with a scored commutator, failed bearings, or open windings needs replacing.
Discount Cleaning Products is an authorized dealer with US-based product support. Our staff works with this equipment every day and can confirm fitment against your model or motor tag before you order, so the part you receive is the part your machine actually takes.
