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SKU:
ZZ3F09044
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Neutral Switch Shift 8M0052939 Fit Mercury TDI 4.2L 370 MCM/MIE, 335 MCM
$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
This neutral safety switch 8M0052939 is a direct replacement component for Mercury marine engines, allowing the engine to start only when the transmission is in neutral. It is specifically designed for the TDI 4.2L 370 MCM/MIE and 335 MCM models, ensuring safe and dependable operation every time.
Overview
This neutral switch shift is a safety-critical part that prevents the engine from cranking in gear. It fits Mercury TDI 4.2L 370 MCM and MIE as well as 335 MCM engines, working with the shift mechanism to inhibit starting when a gear is engaged. This switch is built to endure harsh marine conditions, delivering reliable performance for engine protection and operator safety.
Built For Performance
- OEM cross-reference number 8M0052939 ensures a precise fit and function
- Sealed construction protects against water, oil, and salt exposure
- Positive engagement mechanism provides a clear and reliable signal
- Corrosion-resistant terminals maintain solid electrical contact
- Utilizes standard marine-grade wiring for simple integration
- Tested for consistent switching in high-vibration environments
Fits These Machines
- for Mercury TDI 4.2L 370 MCM
- for Mercury TDI 4.2L 370 MIE
- for Mercury TDI 4.2L 335 MCM
- for Mercury TDI 4.2L 335 MIE
On-The-Job Use
- Required for safely starting the engine after maintenance or winterization
- Used when troubleshooting intermittent starting problems or a no-crank condition
- Operates effectively in both clockwise and counterclockwise shift installations
- Helps verify the shift linkage is correctly adjusted on the 4.2L diesel engine
Specs At A Glance
| Part Number(s) | 8M0052939 |
| Type | Neutral safety switch |
| Circuit | Normally open (closed in neutral) |
| Voltage | 12V DC |
Good To Know
Q: What happens if this switch fails? A: The engine may fail to start in neutral or start in gear, which is a safety hazard. Replacing it with this direct-fit part restores proper starting function.
Q: Can this switch be tested before installation? A: Yes, you can check continuity across the terminals while moving the shift lever from neutral to gear; the switch should show continuity only in the neutral position.
Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.