Johnson 28HP 2-Stroke Outboard Engine Parts

(15 products)

This page focuses on Johnson 2-Stroke 28HP outboard engines and helps you find compatible parts and service information. Below you’ll find maintenance tips, common replacement parts, and troubleshooting guidance. You can also browse the main Johnson/Evinrude collection, and at the bottom of this page you can start browsing parts for this engine. On the collection page, use the Filter & Sort controls to narrow results by horsepower, year range, and part category/section.

Browse All Johnson Parts

How to Identify Your 28HP Model

Locate the nameplate/serial plate on the transom bracket or swivel bracket. Record both the model number and the serial number.
Model codes typically indicate shaft length (e.g., S short, L long), starting/control type (e.g., E for electric start), and a year/series suffix. Use the full code to verify parts compatibility.
Most 28HP Johnson units are 2-stroke, carbureted twin-cylinder engines. If equipped with an external oil tank or VRO system, note whether the engine uses oil injection or premix fuel.
Measure the driveshaft housing to confirm shaft length (commonly 15" short or 20" long) since some gearcase, prop, and mounting parts vary by shaft length.

Engine Overview

Johnson 28HP 2‑Stroke Platform

Feature	Description
Configuration	Inline-2, carbureted 2-stroke with CDI ignition; manual or electric start.
Common Models	Johnson 28HP 2-stroke models in short/long shaft with rope- or electric-start variants.
Advantages	Lightweight, simple to service, strong low‑speed torque, widely supported parts availability.
Notes	Premix (commonly 50:1) on many models; some may have oil injection. Verify shaft length and starting type when selecting gearcase, propeller, and electrical components.

Routine Maintenance & Service Parts

Intervals below are general guidelines for typical recreational use. Always follow the official service manual for your exact model and operating conditions.

Item	Interval*	Remarks	Parts Link
Gear oil (lower unit)	Every 100 hours or annually	Check for water intrusion/metal. Replace seals if contamination is present.	Johnson/Evinrude
Spark plugs	Inspect 50 hours; replace 100 hours or annually	Use correct heat range and gap. Replace if fouled or worn.	Spark plug
Fuel filter / inline filter	Every 50–100 hours or each season	Replace more often with stale fuel or debris. Check primer bulb and lines.	Fuel Filters
Water pump impeller / kit	Every 2 seasons or ~100 hours	Replace impeller and inspect housing/plate; sooner if weak telltale or overheat.	Johnson/Evinrude/OMC Water Pump Repair Kits
Anodes (zincs)	Inspect every 50 hours; replace when 50% consumed	Use alloy matched to water (salt, brackish, fresh). Ensure good electrical contact.	Johnson/Evinrude/OMC Anodes
Premix fuel/oil ratio (if no oil injection)	Every fill-up	Most models run 50:1 with TC‑W3 oil. Verify your model’s specification.	Johnson/Evinrude
Oil injection (VRO) system inspection (if equipped)	Each season	Inspect hoses, clamps, and pump operation; confirm alarm function.	Johnson/Evinrude/OMC Hoses
Lower unit seals (if water found in oil)	As needed	Pressure/vacuum test gearcase; reseal if leakage is detected.	Johnson/Evinrude/OMC Lower Unit Seal Kits

Frequently Used Parts Categories

Routine Service Kits – Johnson/Evinrude/OMC Service & Maintenance Kits
Cooling System – Water Pump Repair Kits
Fuel System – Fuel Filters and Fuel Pumps
Ignition / Electrical – Electrical Items and Ignition Switch
Gearcase & Seals – Lower Unit Seal Kits
Propulsion – Johnson/Evinrude/OMC Propellers
Corrosion Protection – Johnson/Evinrude/OMC Anodes

Common Symptoms & Quick Checks

Symptom	Check First	Related Parts
Weak telltale or overheat alarm	Inspect intake screen and telltale hose; verify impeller condition; test thermostat.	Water pump kit, thermostat, intake screen, gaskets
Poor acceleration or power loss	Check prop damage/slip, fuel quality, clogged filters, carb settings, and compression.	Propeller, fuel filter, carburetor kit, spark plugs
Hard starting or rough idle	Verify choke/primer operation, plug gap and spark, and for air leaks in fuel lines/primer bulb.	Spark plugs, primer bulb, fuel hoses, carburetor kit
Excessive smoke (2-stroke)	Confirm premix ratio; check for stuck choke, rich idle mixture, or low operating temperature.	Spark plugs, carb jets/needles, thermostat
Gearcase noise or metal in gear oil	Inspect for water in oil; pressure/vacuum test; check prop shaft seals and bearings.	Lower unit seal kit, bearings, shims

FAQs

Are parts interchangeable between different years or platforms?

Some service items interchange across multiple years, but many components vary by model code, shaft length, and ignition/fuel configuration. Always use the full model number to confirm compatibility.

When should the impeller be replaced?

Replace the impeller about every 2 seasons or ~100 hours, and sooner if the telltale weakens, you ingest debris, or the engine overheats. In sandy or shallow use, inspect more frequently.

How often should the lower unit gear oil be changed?

Change gear oil every 100 hours or annually. If you see milky oil, metal, or water intrusion, service immediately and pressure/vacuum test the gearcase.

What information do you need to confirm part fitment?

Provide the complete model number, serial number, shaft length, starting type (manual/electric), and any notes about oil injection vs. premix. Photos of the nameplate and the part in question are helpful.

Ready to find parts for your Johnson outboard? Browse the main Johnson/Evinrude collection and narrow by horsepower, year, and model.

Shop Johnson/Evinrude Parts

If you’re unsure about your model, send us a photo of the nameplate and the part you need and we’ll help verify compatibility.