1956–1970 Johnson Evinrude 1.5 HP to 40 HP Outboard Motor Repair Manual 1956–1970

This Seloc repair manual covers listed 1956–1970 Johnson and Evinrude 1- and 2-cylinder, two-cycle outboards from 1.5 to 40 hp. Procedures are grouped by engine design and horsepower, with year-by-year model cross-references in the Appendix.

PDF Search, Bookmarks, and Wiring Detail

Search and diagram access: Text search works through the main chapters, although recognition errors and image-based wiring labels limit some searches. Embedded bookmarks provide access to the contents, main chapters, Appendix, and wiring section. Small wiring labels require an enlarged view.

One printable English PDF contains 423 pages total: 392 pages of main chapters, a 25-page Appendix, four contents pages, one blank page, and one notes page. All of these pages are included in the total.

Powerhead, Fuel, and Lower-Unit Service

These selected service topics outline the repair coverage. Other sections discuss propeller selection and corrosion control.

• Powerhead repair: Cylinder-head and reed service, crankcase separation, piston and crankshaft inspection, cylinder honing, reassembly, installation, and post-overhaul break-in.

• Lower units: Step-by-step removal, water-pump service, internal inspection, reassembly, adjustment, and installation for no-shift, manual-shift, and Electromatic designs.

• Fuel systems: Type I, II, and III carburetor overhaul, choke service, fuel-pump and line tests, pressure-tank repair, and late-model tank service.

• Ignition and electrical systems: Flywheel-magneto troubleshooting, fuel/ignition synchronization, charging-circuit diagnosis, and Delco-Remy, Autolite, and Prestolite starter-motor service.

• Controls and hand starters: Mechanical and electric shift-box repair, Evinrude pushbutton controls, cable adjustment, and overhaul of three hand-starter designs.

• Service references: Component torque tables, powerhead clearances and wear data, tune-up specifications, gear-oil capacities, and starter, generator, regulator, condenser, and rope specifications.

The manual is suited to experienced owners and mechanics who can match the engine identification to the model tables and are comfortable with precision measurement, electrical testing, pullers, and bearing-installation tools.

Model and Procedure Selection

Not every horsepower applies to every model year. The 15 hp and 30 hp entries are limited to 1956, the 28 hp to 1962–64, and the 35 hp to 1957–59; 1.5 hp coverage begins in 1968 and 4 hp coverage in 1969.

All covered engines use flywheel-magneto ignition. Carburetor, starting, charging, and gearcase procedures must be matched to the installed equipment rather than selected by horsepower alone.

Powerhead Overhaul and Assembly Differences

Powerhead work starts with two-cycle operating theory, including cross-flow and loop-scavenged designs. Internal service extends to bypass and exhaust covers, upper and lower seals, connecting rods, piston rings, crankshaft inspection, and cylinder-block service.

Crankshaft installation is divided into three groups: 15–40 hp engines; 1.5, 5, 5.5, 6, and 9.5 hp engines; and 3, 4, and 7.5 hp engines. The procedures distinguish needle-bearing and babbitt-bearing arrangements instead of treating every powerhead alike.

Installing the tapered crankcase centering pins from the small-hole side can break the crankcase cover or cylinder block. The head-installation section also warns that automotive head-gasket sealer can cause electrolytic attack on the aluminum cylinder block.

Carburetors, Chokes, and Fuel Pumps

Choke service separates heat/electric, all-electric, and water-operated arrangements. The fuel chapters connect rough idle and excessive consumption diagnosis with carburetor inspection, fuel delivery, and synchronization.

Fuel-pump repair has a specific limit: Internal rebuilding is described for the illustrated serviceable pump. Other pump designs receive filter-screen service and replacement guidance rather than a general internal-overhaul procedure.

Gearcase Diagnosis and Electromatic Repair

Lower-unit procedures separate 1.5–4 hp no-shift, 5–25 hp manual-shift, 28–40 hp manual-shift, and 40 hp Electromatic electric-shift designs.

Troubleshooting addresses failure to engage forward or reverse, water intrusion, propeller-hub slip, difficult shifting, and jumping out of gear. It also explains how a locked gearcase can imitate a seized powerhead, helping distinguish the affected assembly before powerhead overhaul is considered.

The Electromatic section traces the battery, control box, green and blue shift leads, wiring, and forward/reverse coils before teardown. Assembly guidance distinguishes the babbitt-bearing, knurled forward hub from the needle-bearing, smooth reverse hub. Some photographs show a V4 assembly; the accompanying text identifies the 40 hp washer differences.

Special tools: Callouts include OMC coil remover 379784 with kit 379843, seal puller 377565, and bearing remover 309916. Bearing and race work references 378737, 309033, 309932, and 379247; forward-coil installation uses 379230.

Starting Systems, Controls, and Seasonal Care

Electrical fault isolation covers the wiring harness, generator, regulator, gauges, choke and starter circuits, solenoid, and starter drive gear. The separate starter-motor sections include disassembly, armature testing, inspection, and assembly.

Hand-starter repair distinguishes cylinder-and-pinion, coil-spring/swing-arm, and flywheel-mounted designs, including versions with return springs, without return springs, and with a single nylon pawl.

Maintenance coverage adds engine-number identification, submerged-engine service, winter storage, battery storage, lower-unit upkeep, and preseason preparation.

Exploded Views and Wiring References

Illustrations include the complete two-cycle piston-cycle diagram and exploded views of the 1.5, 9.5, 10, and 15–40 hp powerhead groups. Type I and II carburetor views, the pressure fuel tank, and the flywheel magneto support component identification.

Drivetrain and electrical drawings cover no-shift, Weedless, manual-shift, and Electromatic gearcases, plus the three starter-motor families.

Appendix wiring drawings distinguish 33 hp generator systems for 1965–70, the 35 hp system for 1957–59, and 40 hp standard- and electric-shift generator systems in several year groups. A separate 20/25 hp drawing is listed as 1971–72 in the contents; that reference does not extend the manual’s general repair coverage beyond 1970.

Service Safety

Before powerhead disassembly, the manual calls for the battery and fuel lines to be disconnected. Pressure-tank repair also requires residual tank pressure to be released and fuel vapors kept away from smoking, sparks, and open flame.

Selected Electromatic Test Specifications

For the 40 hp Electromatic lower unit, the shift-coil checks specify 4.5–6.5 ohms from each disconnected forward or reverse lead to ground, with the ignition off and the control in neutral.

The accompanying current-draw checks use readings above 2.5 amps in either gear as a trigger for further wiring, switch, and coil diagnosis.