Sierra 18-99425 Timer Base for Johnson/Evinrude 4-Cyl Loop Charged Outboards, 1988-2001, 120-140 HP, Replaces 763782

The Sierra 18-99425 is a timer base assembly for the ignition system of 1988-2001 Johnson/Evinrude 4 cylinder loop charged outboard engines equipped with Quick Start and S.L.O.W. Features, covering the 120, 125, 130, 135, and 140 HP models. The timer base is a core ignition timing component that works with the engine's electronic ignition system to help maintain correct spark timing across the engine's operating range. It is constructed of metal for durability in the marine engine compartment environment. This part is built as a direct fit for the listed engine range, allowing it to be installed in place of the original equipment timer base without modification to the surrounding ignition components. It cross-references to OEM part numbers 763782 and 583508, so buyers can confirm compatibility using either of those numbers in addition to the Sierra 18-99425 part number. At 0.9 pounds and measuring 1 inch by 1 inch by 1 inch, it is a compact component designed to mount within the existing ignition housing of the covered outboard models.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-99425
• Product Type: Timer Base (Ignition System)
• Material: Metal
• Dimensions: 1 inch x 1 inch x 1 inch (D x W x H)
• Weight: 0.9 pounds
• Engine Compatibility: Johnson/Evinrude 4 cylinder loop charged engines with Quick Start and S.L.O.W.
• Horsepower Range: 120, 125, 130, 135, and 140 HP
• Model Years: 1988-2001
• OEM Cross Reference: 763782, 583508

Fitment

• Johnson/Evinrude 4 cylinder loop charged outboard engines with Quick Start and S.L.O.W., 1988-2001, 120, 125, 130, 135, and 140 HP

Replaces (OEM)

• 763782
• 583508

Frequently Asked Questions

What engines does the Sierra 18-99425 timer base fit? The Sierra 18-99425 fits 1988-2001 Johnson/Evinrude 4 cylinder loop charged outboard engines equipped with Quick Start and S.L.O.W., covering the 120, 125, 130, 135, and 140 HP models.

What OEM part numbers does the 18-99425 timer base replace? It replaces OEM part numbers 763782 and 583508, so either of those numbers can be used to confirm the correct fit before ordering.

What is the timer base made of? The 18-99425 timer base is constructed of metal, suited to the operating environment inside an outboard's ignition housing.

How big is the Sierra 18-99425 timer base? It measures 1 inch by 1 inch by 1 inch (depth x width x height).

How much does the 18-99425 timer base weigh? It weighs 0.9 pounds.

What does a timer base do in an outboard ignition system? A timer base such as the 18-99425 is a core component of the engine's electronic ignition system, working to help maintain correct spark timing as the engine runs.

Does the 18-99425 support Quick Start and S.L.O.W. Ignition features? Yes, the 18-99425 is designed for engines equipped with Quick Start and S.L.O.W., which are features found on the covered 1988-2001 4 cylinder loop charged Johnson/Evinrude engines.

Can the 18-99425 be installed in place of the original timer base without other changes? Yes, the Sierra 18-99425 is built as a direct fit for its listed engine range and cross-references to OEM numbers 763782 and 583508, allowing installation in place of the original timer base.

Is the 18-99425 a genuine Sierra part? Yes, part number 18-99425 is a Sierra manufacturer part number for the timer base assembly covering the listed Johnson/Evinrude 4 cylinder engines.