CDI Electronics Outboard Ignition Troubleshooting Guide

215 Appendix Appendix No. 032410 March, 2010 Subject: 35 Amp Stator Power Coil Over-Heating. Make: Johnson & Evinrude Horsepower: 200/225/250 HP V6 Years: 1993 through 2001 Problem: The engine and electrical system can become damaged by overheating when air is trapped in the upper part of the cooling system. Trapped air can cause the regulator/rectifier to overheat, resulting in damage to the regulator (also damaging the stator) which is not covered under warranty. Air can become trapped in the top of the block at engine start-up when: a) The engine is idling with a blocked or restricted thermostat. b) The engine is started and is not accelerated beyond 1800 RPM (the pop-off valve is designed to open and allow additional cooling water to circulate through the block when the RPM exceeds 1800 RPM). With age and wear, the seal for the pop-off valve plunger gradually conforms to the shape of the plunger and traps air in the top portion of the block. This prevents water from getting to the cooling fins of the regulator/rectifier, causing the regulator/rectifier to overheat and stressing the Stator. The first failure is typically the Power Coil on the Stator, progressing to damage to the rest of the Stator, Power Pack and regulator/rectifier. Air can also become trapped in the top of the block if: a) The engine is operated in aerated water, such as a pontoon or deck boat wakes. b) The engine is operated too high on the transom. Solution: 1. Remove the pop-off valve and disassemble it. 2. Using a 1/8” drill bit, drill a hole through the plunger from the back side of the plunger as close to the center as possible. This allows air to be vented from the top of the cooling system and helps ensure an adequate water level when the engine is run below 1800 RPM. 3. Re-assemble the pop-off valve and re-install it in the block as per the service manual. NOTE: It is recommended that the rectifier/regulator be replaced after the modification has been done as some of the rectifier/regulator’s internal parts may have un-detectable damage.