Sierra Timer Base 18-99417 for Johnson/Evinrude 4 Cyl Cross Flow Engines, Replaces 763783
Sierra Timer Base 18-99417 for Johnson/Evinrude 4 Cyl Cross Flow Engines, Replaces 763783
The Sierra 18-99417 is a timer base for Johnson/Evinrude 4 cylinder Cross Flow outboard engines equipped with twin power pack ignition systems. The timer base is the component that generates the timing signal the power packs use to fire the ignition at the correct point in the engine cycle, so a worn or failed unit typically shows up as rough running, misfires, hard starting, or a no-spark condition on one or more cylinders. This unit is built to take the place of the original Johnson/Evinrude timer base and is cross-referenced to the OEM part numbers used across this engine family, giving owners a sourcing option when the original factory part is hard to find.
It is designed specifically for 4 cylinder Cross Flow powerheads covering the 85, 88, 90, 100, 110, 115, and 140 HP range that use twin power packs, so it should be matched against the engine's HP and ignition configuration before ordering. The unit weighs 0.9 pounds and ships as a single timer base assembly.
Specifications
- Brand: Sierra
- Manufacturer Part Number: 18-99417
- Product Category: Evinrude Outboard Ignition System
- Weight: 0.9 pounds
- Product Dimensions: 8 x 5 x 3 inches
- UPC: 808282394486
- Ignition Type: Twin power pack
Fitment
- Johnson/Evinrude 4 cylinder Cross Flow engines with twin power packs
- 85, 88, 90, 100, 110, 115, and 140 HP
- 1978-1987
Replaces (OEM)
- 763783
- 583376
- 582041
- 581812
- 583127
- 583128
Frequently Asked Questions
What is the Sierra 18-99417 timer base used for? It supplies the timing signal for the ignition system on Johnson/Evinrude 4 cylinder Cross Flow outboards that use twin power packs, so it directly affects when each cylinder fires.
Which engines does the 18-99417 timer base fit? It is built for Johnson/Evinrude 4 cylinder Cross Flow engines with twin power packs in the 85, 88, 90, 100, 110, 115, and 140 HP range, model years 1978-1987.
What OEM part numbers does this timer base replace? The Sierra 18-99417 cross-references to Johnson/Evinrude OEM numbers 763783, 583376, 582041, 581812, 583127, and 583128.
How much does the 18-99417 timer base weigh? This timer base weighs 0.9 pounds.
What are the dimensions of the timer base? The Sierra 18-99417 measures approximately 8 x 5 x 3 inches.
Does this timer base work with single power pack ignition systems? No. The 18-99417 is designed for Johnson/Evinrude 4 cylinder Cross Flow engines equipped with twin power packs, not single power pack setups.
How do I know if my timer base needs replacing? Symptoms of a failing timer base on these Johnson/Evinrude Cross Flow engines include misfiring, rough idle, hard starting, or loss of spark on one or more cylinders.
Is the 18-99417 a genuine Sierra part? Yes, part number 18-99417 is a Sierra-branded timer base manufactured as a replacement for Johnson/Evinrude 4 cylinder Cross Flow ignition systems.
What is included when I order the 18-99417? The order includes one Sierra 18-99417 timer base unit.
Will the 18-99417 fit an Evinrude engine outside the 1978-1987 range? The 18-99417 is specified for the 1978-1987 model years on the listed 4 cylinder Cross Flow HP range, so engines outside that range should be checked against their own OEM part number before ordering.