Sierra 18-5406 Delco Distributor Rotor, Replaces OMC 986651, for GM 4 Cylinder Marine Engines with Delco EST Ignition

The Sierra 18-5406 is a Delco-style distributor rotor built as a direct replacement for marine ignition systems using a Delco EST distributor. It mounts inside the distributor cap and rotates with the distributor shaft to direct high-voltage current from the coil to each spark plug lead in firing order, making it a core wear item in any tune-up or ignition service. The rotor is designed to fit GM 4 cylinder engines equipped with Delco EST ignition, a common configuration on inboard marine powerplants. Its contact surface has a machined finish for reliable, consistent electrical contact with the distributor cap terminals. Sierra engineers this rotor to meet or exceed the performance of the original equipment part it replaces, and it cross-references directly to OMC, GLM, Mallory, Mercruiser, and Volvo Penta part numbers, so it is a straightforward swap whether you are doing a routine ignition tune-up or replacing a worn or cracked rotor. As with all Sierra parts, it is intended to restore factory ignition performance and is backed by Sierra's standard product warranty.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-5406
• Product Type: Distributor Rotor (Delco style)
• Application: GM 4 Cylinder marine engines with Delco EST ignition
• Exterior Finish: Machined
• Included Components: Rotor
• Quantity: 1
• Weight: 0.03 pounds
• UPC: 030999563736

Fitment

This rotor fits GM 4 Cylinder marine engines equipped with Delco EST ignition.

Replaces (OEM)

• OMC 986651
• GLM 71120
• Mallory 9-29220
• Mercruiser 811636
• Mercruiser 898253011
• Mercruiser 811636-1
• Mercruiser 8M001254
• Mercruiser 802468
• Volvo Penta 3854261

Frequently Asked Questions

What engines does the Sierra 18-5406 rotor fit? The Sierra 18-5406 is designed for GM 4 Cylinder marine engines equipped with Delco EST ignition.

Is the Sierra 18-5406 a genuine OEM part or aftermarket? It is a Sierra aftermarket replacement rotor, engineered to meet or exceed the performance of the original equipment rotor it replaces.

What OEM part numbers does the 18-5406 rotor cross-reference to? The Sierra 18-5406 replaces OMC 986651, GLM 71120, Mallory 9-29220, Mercruiser 811636, 898253011, 811636-1, and 8M001254, Mercruiser 802468, and Volvo Penta 3854261.

How much does the 18-5406 distributor rotor weigh? The Sierra 18-5406 rotor weighs 0.03 pounds.

What finish does the rotor's contact surface have? The Sierra 18-5406 rotor has a machined finish on its contact surface for consistent electrical contact inside the distributor cap.

What is included when I order part number 18-5406? The order includes one Sierra 18-5406 rotor; a matching Sierra distributor cap is sold separately.

Will this rotor work with a Delco EST distributor cap from another brand? Yes, the Sierra 18-5406 is a Delco-style rotor that cross-references to OMC, GLM, Mallory, Mercruiser, and Volvo Penta equivalents, so it fits distributor caps built for those same Delco EST applications.

When should the distributor rotor be replaced? A distributor rotor like the Sierra 18-5406 should be replaced during a routine ignition tune-up or whenever the contact tip shows wear, pitting, or cracking that can cause misfires.

Does Sierra offer a warranty on the 18-5406 rotor? Yes, the Sierra 18-5406 rotor is covered under Sierra's standard product warranty.

Is installation of the 18-5406 rotor straightforward? The Sierra 18-5406 is a direct-fit replacement rotor that installs onto the distributor shaft in place of the original Delco-style rotor, using the same mounting configuration as the OEM part.