LiftMaster K16-50108 4L300 V-Belt Replacement Belt for CSW200UL Swing Gate Operators
The LiftMaster K16-50108 is a 4L300 V-belt replacement part for select CSW200UL swing gate operator applications. In a CSW200UL-style swing gate operator, the motor belt is part of the drive path that transfers motor output into the operator's mechanical reduction and gate movement system. A worn belt can slip, squeal, glaze, stretch, crack, or shed belt dust inside the operator. When the belt loses grip, the motor may run without moving the gate correctly, or the gate may move inconsistently under load. K16-50108 is commonly listed as the 4L300 V-belt and is also known as Elite Q042. The strongest compatibility references tie it to LiftMaster CSW200UL swing gate perimeter access systems. Because LiftMaster gate operators use multiple belt sizes across slide and swing platforms, do not choose this belt by general appearance. Confirm the old belt marking, pulley arrangement, and operator parts diagram. If the old belt failed quickly, inspect the gate arm, gearbox, pulleys, tensioning method, and gate movement before installing the replacement.
Compatible With
This compatibility section is written from the available parts references and should be checked against the operator model label, old part number, and replacement parts diagram before ordering.
- LiftMaster CSW200UL swing gate operators where K16-50108 is listed
- LiftMaster CSW200UL swing gate perimeter access system references using 4L300 belt Q042
- Select CSW200-style applications only when the parts diagram calls for K16-50108 / 4L300
- Elite Q042 belt service applications by exact diagram
- Swing gate operator drive belt applications requiring a 4L300 belt
- Not a substitute for K16-50094, 4L220, Q020, or SL3000 slide gate belts
Also Known As / Related Part Numbers
Features & Specifications
| Feature / Specification | Details |
|---|
| Manufacturer | LiftMaster |
| Product Type | Gate operator V-belt |
| Part Number | K16-50108 |
| Application | Drive belt replacement for select CSW200UL swing gate operators |
| Compatible Operator Type | Select commercial swing gate operators |
| Belt Size | 4L300 |
| Related Numbers | Q042, 4L300 |
| Notes | Verify belt size, pulley alignment, and operator parts diagram before ordering |
Technician Note
A belt that fails early is often a symptom. Check pulley alignment, tension, gearbox drag, arm binding, and gate movement. A hard-to-move gate can overload and wear the replacement belt quickly.
Before Ordering Checklist
- Confirm the operator parts diagram lists K16-50108, 4L300, or Q042.
- Verify the operator is a CSW200UL-style swing gate system, not an SL3000 slide gate operator.
- Compare the old belt markings and length.
- Inspect pulleys, motor mount, belt tension, and gate arm movement.
- Do not substitute a 4L220 belt for a 4L300 belt.
Professional Advisory
Disconnect power and secure the gate before belt service. If the gate arm or gearbox is binding, have a qualified gate technician correct the mechanical issue before putting the operator back in use.
Product Questions and Answers
What belt size is K16-50108?
K16-50108 is commonly listed as a 4L300 V-belt.
Is K16-50108 also known as Q042?
Yes, Q042 is commonly used as an Elite reference for this 4L300 belt.
Which operator commonly uses this belt?
The strongest references tie it to LiftMaster CSW200UL swing gate operator applications where the parts diagram calls for K16-50108.
Can I use this belt on an SL3000?
No. SL3000 references commonly use K16-50094 / 4L220 / Q020, not K16-50108 / 4L300.
What should I check if the old belt slipped?
Check belt tension, pulley alignment, pulley wear, gearbox drag, gate arm movement, and whether the gate itself moves freely.
