Sierra 18-99426 Johnson Evinrude 4 Cylinder Timer Base, Fits 1973-1977 85-140 HP, Replaces 581900

The Sierra 18-99426 is a timer base built for Johnson/Evinrude 4 cylinder outboard engines, a core ignition-system component that works with screw terminal power packs to control ignition timing. This timer base is a direct-fit replacement for the original equipment part, restoring correct ignition timing function on applicable Johnson/Evinrude outboards. It fits 1973-1977 4 cylinder engines rated at 85, 155, 135, and 140 HP that use screw terminal power packs.

As an ignition-system replacement part, the timer base is intended for outboard owners and marine technicians replacing a worn, damaged, or failing original timer base. Installing the correct timer base is important to maintaining proper ignition timing and engine performance on these Johnson/Evinrude 4 cylinder models.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-99426
• Product Type: Ignition Timer Base
• Category: Evinrude Outboard Ignition System
• UPC: 808282394578
• Weight: 0.8 pounds
• Cylinder Count: 4
• Engine Compatibility: Johnson/Evinrude 4 cylinder outboards, 85, 155, 135 and 140 HP, with screw terminal power packs
• Fitment Years: 1973-1977
• OEM Cross Reference: 581900, 581300, 763778, 385433

Fitment

• Johnson/Evinrude 4 cylinder outboards, 1973-1977, 85, 155, 135 and 140 HP, with screw terminal power packs

Replaces (OEM)

• 581900
• 581300
• 763778
• 385433

Frequently Asked Questions

What does the Sierra 18-99426 timer base fit? The Sierra 18-99426 fits Johnson/Evinrude 4 cylinder outboard engines from 1973-1977, specifically 85, 155, 135, and 140 HP models that use screw terminal power packs.

Is the 18-99426 compatible with 6 cylinder Johnson/Evinrude engines? No. The Sierra 18-99426 timer base is designed specifically for 4 cylinder Johnson/Evinrude outboard engines, not 6 cylinder models.

What OEM part numbers does this timer base replace? Sierra 18-99426 replaces OEM numbers 581900, 581300, 763778, and 385433 on applicable Johnson/Evinrude 4 cylinder outboards.

How much does the timer base weigh? The Sierra 18-99426 timer base weighs 0.8 pounds.

Does this timer base work with all Johnson/Evinrude power pack types? The 18-99426 is built for use with screw terminal power packs on 1973-1977 4 cylinder Johnson/Evinrude engines; it is not specified for other power pack terminal types.

What horsepower engines use the 18-99426 timer base? This timer base fits 85, 155, 135, and 140 HP Johnson/Evinrude 4 cylinder outboards from 1973-1977.

Is the Sierra 18-99426 a direct OEM replacement? Yes, the 18-99426 is a direct replacement for the original timer base on the listed Johnson/Evinrude 4 cylinder engines, matching OEM numbers 581900, 581300, 763778, and 385433.

What ignition system does this timer base belong to? The Sierra 18-99426 is part of the Evinrude outboard ignition system, functioning as the timer base component.

How do I know if my Johnson/Evinrude engine needs this timer base? If your Johnson/Evinrude 4 cylinder outboard is a 1973-1977 model rated at 85, 155, 135, or 140 HP with a screw terminal power pack, the Sierra 18-99426 is the correct timer base part number to check against your engine's original part number.

What brand manufactures part number 18-99426? Part number 18-99426 is manufactured by Sierra.