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74039 Marine Propeller Lock for Mercury MerCruiser OMC 3/4 Inch 16 Thread Size
$94.09
Sale price
$94.09
Regular price
Available to Order
This marine propeller lock set is a propeller lock set compatible with Mercury, MerCruiser, and OMC outdrives with 3/4"-16 thread size and matches Part# 74039.
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Product Overview
This marine propeller lock set replaces your standard propeller nut to deter theft and secure your propeller. It threads onto 3/4"-16 propeller shafts found on many Mercury, MerCruiser, and OMC sterndrives and outboards. Boaters needing a simple, keyed deterrent rely on this marine propeller lock set for peace of mind at the dock or on the trailer.
Key Features & Performance
- Keyed locking design prevents unauthorized propeller removal
- Precise 3/4"-16 thread pitch mates securely with factory shafts
- Hardened stainless steel components resist corrosion in salt and fresh water
- Direct replacement for the standard propeller nut—no modifications needed
- Set includes lock nut, washer, and matching installation key
Fitment & Compatibility
- Mercury and MerCruiser Alpha, Bravo, and outboard drives with 3/4"-16 propeller shaft threads
- OMC Cobra and select sterndrives with 3/4"-16 shaft thread diameter and pitch
- Any marine propeller shaft meeting the 3/4"-16 thread specification
Common Uses
- Securing stainless steel or aluminum propellers on trailered boats
- Replacing a lost or damaged propeller lock nut and key
- Wet-slipped boats exposed to opportunistic theft
- Pre-season commissioning and propeller inspection
Technical Specifications
- Part Number(s): 74039
- Thread Size: 3/4"-16
- Compatible Brands: Mercury, MerCruiser, OMC
Frequently Asked Questions
Q: Does this lock set come with a key? A: Yes, it includes the unique key required to install and remove the locking nut.
Q: Will this fit my Mercury outboard? A: If your propeller shaft has 3/4"-16 threads, this lock set threads on directly without adapters.
Product appearance and specifications may vary slightly by batch. Compatibility may vary by serial number. Verify fitment before purchase.