If you already know your part number, browse our Exmark PTO clutch collection to find a direct replacement for your mower.
If your Exmark Quest blades are not engaging, slipping under load, or cutting inconsistently, the issue is often related to a worn PTO clutch or supporting deck components.
This guide covers PTO clutch fitment, serial-based differences, and how to identify the correct replacement parts for Exmark Quest mower applications.
Exmark Quest PTO Clutch Fitment
Exmark Quest models use multiple PTO clutch configurations depending on serial number range, engine package, and deck size. The two most common clutch platforms are the 110-6766 and 116-1604 families.
Identifying the correct clutch requires confirming your model and serial number or matching the OEM part number stamped on your original clutch.
PTO Clutch by Serial Number Range
110-6766 Clutch Platform (Earlier / Specific Serial Ranges)
The following Exmark Quest models and serial ranges commonly use the 110-6766 clutch platform:
- SN 670,000+: QST22BE482, QST24BE522
- SN 720,000+: QST23KC482, QST23KC522
- SN 790,000+: QST20BE422
- SN 920,000+: QT24KA501
- Quest E-Series 50: Serial 312,000,000 and up
A direct replacement for this platform is the 110-6766 PTO clutch, designed for consistent blade engagement and reliable performance.
Deck Components for 110-6766 Fitment Range
For Exmark Quest models within the 110-6766 clutch platform, deck and spindle components are largely standardized, with variation based on deck size.
Common Spindle Assembly (All Deck Sizes)
- Spindle Assembly: 116-5712
- Replaces: 109-6394, 109-8744, 116-3497, 121-5681
- Compatible Models: QST20BE422, QST22BE482, QST23KC482, QST23KC522, QST24BE522
42-Inch Deck (SN 790,000+)
- Deck Belt: 108-6645-SL
- Blades: 103-6401-S, 109-9982-S
- Deck Shell: 109-9971
48-Inch Deck (SN 670,000+ / 720,000+)
- Deck Belt: 109-5364
- Blades: 103-6381, 116-5177
- Spindle Pulley: 1164875, 109-3747
50-Inch Deck (Quest E-Series SN 312,000,000+)
- Deck Belt: 119-8820
- Blades: 115-5059-03
- Spindle Assembly: 121-0751
- Spindle Shaft: 117-7268
52-Inch Deck (SN 670,000+ / 720,000+)
- Deck Belt: 109-5364
- Blades: 103-6381, 109-6872
- Spindle Pulley: 1164875
Because these components vary by deck size and configuration, confirming your model and serial number ensures accurate part selection.
116-1604 Clutch Platform (Alternate Configuration)
Other Exmark Quest models use the 116-1604 clutch platform, commonly found across 42", 48", and 52" deck configurations.
This platform includes OEM part numbers such as 116-1604, 109-9282, and 917-04967.
A direct OEM-spec replacement for this group is the 116-1620 PTO clutch, engineered to match original fitment, mounting, and performance specifications.
Although the replacement part number differs, it is designed to meet the same operational requirements as the original clutch.
This clutch also covers a broader range of OEM cross-reference numbers and commercial applications. For a full breakdown, see our 116-1620 cross reference guide.
Deck and Drive System Components
The PTO clutch works in conjunction with several wear components. When diagnosing blade engagement issues, inspect the full deck system:
- Spindle Assembly: 139-3214, 116-5712 (model dependent)
- Deck Belt: 119-8819-SL, 109-5364, 109-3661-SL (deck size dependent)
- Blades: Various 42", 48", and 52" configurations
- Idler Pulleys: 132-9420, 132-4718
Worn belts, pulleys, or spindles can produce symptoms similar to PTO clutch failure, including slipping, poor cut quality, or inconsistent blade speed.
Common Signs of PTO Clutch Failure
- Blades will not engage when the PTO switch is activated
- Intermittent or weak engagement
- Burning smell or overheating
- Squealing or grinding noise
- Loss of cutting power under load
- Uneven or inconsistent cut quality
If these symptoms appear, replacing the PTO clutch early can prevent belt damage and restore proper cutting performance.
Where Is the PTO Clutch on an Exmark Quest?
The electric PTO clutch is mounted directly beneath the engine on the crankshaft and sits above the mower deck belt system. It engages the blades when the PTO switch is activated.
Inspection typically requires accessing the underside of the mower near the engine pulley. Raising the mower safely or removing the deck can improve access.
How to Confirm Fitment
The most reliable way to confirm compatibility is to match the OEM part number stamped on your original PTO clutch.
If the OEM number is worn, missing, or unreadable, use your mower’s model and serial number to verify the correct clutch for your specific configuration.
Because Exmark Quest models span multiple clutch platforms, confirming fitment before ordering is critical.
Related Exmark PTO Clutch Guides
- Exmark Phazer PTO Clutch Replacement
- Exmark PTO Clutch Replacement Guide
- 110-6766 PTO Clutch Fitment Guide
Find the Right PTO Clutch for Exmark Quest
If your Exmark Quest blades are not engaging correctly, selecting the correct PTO clutch based on your model and serial range will restore proper blade operation and cutting performance.
Shop the 110-6766 PTO clutch for compatible serial ranges, or choose the 116-1620 PTO clutch replacement for models using the 116-1604 platform.
You can also browse the full Exmark PTO clutch collection for other Exmark model applications.