Evinrude 33 HP Ski-Twin Electric Model 33552 (1965) Outboard Motor Specifications & Maintenance Guide

The 1965 Evinrude Ski-Twin Electric (Model 33552) combines classic 33 HP two-stroke power with push-button electric start convenience. Built around a 40.5 cubic-inch displacement block, this 140-pound motor is tailored for 15-inch transoms, delivering 33 OBC-certified horsepower at 4,500 RPM. Designed for mid-sized family boats and ski craft, Model 33552 features synchronized throttle/spark controls, forward-neutral-reverse shifting, and integrated remote choke capabilities.

Maintaining peak operational output across its 4,000–5,000 RPM range requires strict adherence to original service guidelines. Proper maintenance—including gapping ignition breaker points strictly to 0.020″, setting spark plug gaps to 0.030″, torquing plugs to 20–20.5 ft-lbs, and verifying carburetor float level flushness—prevents electrical ignition miss, hard starting, and fuel lean conditions.

Maintenance Recap & Tune-Up Checklist

• Electric Start & Ignition Tuning: Inspect electric starter wiring connections, verify magneto breaker points read 0.020″ gap, check condenser range (0.25–0.29 mfd), and torque 14mm spark plugs (Champion J4J / AC-M42K) to 20–20.5 ft-lbs with a 0.030″ gap.
• Fuel System & Carburetor Adjustment: Rebuild single-barrel carburetors with float levels set flush to the casting rim, confirm needle seat gap (0.062″–0.065″), and check line connections to the 6-gallon pressure/suction fuel tank.
• Lower Unit & Water Pump Service: Inspect Centri-matic water pump discharge, maintain clean oil in the 12:21 gear housing, and always keep spare 1/4″ x 1-15/32″ stainless steel drive pins (Part No. 304575) on hand for the 10-3/8″ x 12-1/2″ propeller.
• Powerhead Tolerance Checks: Measure bore wear against standard 3.0625″ piston rings (Part No. 378436), ensuring compression load stays within 6 to 9 lbs and crankshaft journal diameters meet factory parameters.

Technical Specifications