1974 Johnson 40 HP Outboard Motors Service manual, Page 73Get this manual
DESCRIPTION The 40 HP Electric Starting Model electrical system is made up of the amp flywheel alternator, ignition system, the starter system, and the storage batterySee Figure 7-1, Electrical System Schematic at end of Manual Starter, Section 8The starter solenoid and motor cable connector are located in the lower mOlor cover See Figure 7-2
are caused by loose or dirty electrical wiring connectionsstarter system troubleshooting is included in the Trouble Check Chart in Section 2Servicing of the starter solenoid and starter, and battery maintenance, are covered in this Section
BATTERY SPECIFICATIONS
For best performance, we ecommend 12- volt, 70 ampere hour battery, or better, with minimum of minutes cold starting capacity at 300 amperes diScharge, zero degrees Fahrenheit, and 10 second voltage reading of 7.5 voltsThe important thing to remember is that customer' complaint about poor electric starting may be traceable to battery with specifications not conforming to these recommended specificationsBATTERY TESTING SAFETY WARNING BATTERY ELECTROLYTE IS AN ACIDIC SOLUTION AND SHOULD BE HANDLED WITH CAREIF ELECTROLYTE IS SPIL LED OR SPLASHED ON ANY PART OF THE BODY, IMMEDIATELY FLUSH THE EXPOSED AREA WITH LIB ERAL AMOUNTS OF WATER AND OBTAIN MEDICAL AID AS SOON AS POSSIBLE