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SKU:
ZZ3F09048
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Neutral Switch Shift 8M0052939 Fit Mercury CMD QSD 4.2 ES 270 320 350, JP (3.0L)
$101.19
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$101.19
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$101.19
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Compatible Models
We do our best to list all compatible models. Although this may be the part you need, your exact model may not appear below.
Compatible equipment / model
Neutral Switch Shift for Mercury CMD QSD
This is a replacement neutral switch shift assembly, designed for Mercury CMD QSD engines, including the 4.2 ES series and JP (3.0L) models, rated at 270, 320, and 350 horsepower. This component matches OEM cross-reference 8M0052939 and ensures the engine only starts in neutral for safe shift operation. It is a direct service part for maintaining proper starter lockout in these marine diesel engines.
Overview
This neutral switch shift is an electrical safety device that prevents the engine from starting unless the transmission is in neutral. Engineered for Mercury CMD QSD platforms, including the 4.2 ES and JP (3.0L) base engines, this neutral switch shift provides a reliable replacement for a worn original. This part is a direct equivalent to the OEM 8M0052939 neutral switch shift, ensuring seamless integration.
Built For Performance
- Direct replacement for OEM part number 8M0052939
- Designed to meet marine industry standards for durability and reliability
- Sealed housing protects electrical contacts from moisture and salt spray
- Meets original performance specifications for shift interlock
- Compatible with multiple engine variants within the CMD QSD family
Fits These Machines
- for Mercury CMD QSD 4.2 ES 270 models
- for Mercury CMD QSD 4.2 ES 320 models
- for Mercury CMD QSD 4.2 ES 350 models
- for Mercury CMD QSD JP (3.0L) models
On-The-Job Use
- Replacing a defective neutral safety switch during engine service intervals
- Ensuring safe startup when docking or maneuvering in tight spaces
- Used by marine technicians as a standard replacement part for CMD QSD engines
Specs At A Glance
| Part Number(s) | 8M0052939 |
| Type | Neutral Switch Shift |
| Engine Series | CMD QSD 4.2 ES, JP (3.0L) |
| Power Ratings | 270, 320, 350 HP |
Good To Know
Q: Is this switch identical to the original 8M0052939? A: Yes, this item is a direct replacement for the original part number 8M0052939, with the same electrical and mechanical specifications.
Q: Can I install this myself? A: Installation is straightforward if you have basic mechanical skills, but always disconnect the battery and refer to your engine's service manual for the correct procedure.
Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.