In This Issue:

Spring Maintenance

Greetings to our Atomic 4 customers, and welcome to our April 2012 email newsletter. We have compiled the following information that we hope you find helpful. For a complete listing of our Atomic 4 parts & services, you may visit www.moyermarine.com.

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Springtime Blues

Your engine was running perfectly OK when it was hauled out last fall, you've followed the same thorough lay-up procedures that have worked for you for the past 20 years, and you now have every reason to expect an uneventful spring start-up and a trouble-free season, right? Well almost, but not entirely. There's a small list of pesky things that can happen to your engine while your boat just sits there over winter that can greatly complicate your spring commissioning activities. At risk of repeating ourselves, please remember to close your raw water through-hull if your engine does resist your attempt to wake it up during a spring commissioning exercise (or any other time for that matter). While the list is mercifully small, the insidious nature and serious implications of the items contained within the following list deserve our attention at this time of year. 1) CORRODED TERMINALS WITHIN THE PRIMARY IGNITION SYSTEM: The primary ignition circuit extends from the big battery cable on your starter solenoid to the ignition switch, and back to the positive terminal of the coil.Please note here that coils, electric and mechanical fuel pumps, Ignitors, head gaskets and manifold gaskets, etc. have an extremely low likelihood of failing while the engine is sitting idle over a lay-up. In general, it's the nature of corrosion at the interface of electrical connections to deteriorate so slowly that they will usually go through a small period of time (perhaps an entire season) where they will exhibit fickle behavior before completely failing. During this period of time, a particular contact might decide to work on Monday but not on Tuesday, and then might decide to work again on Wednesday but not on Thursday, etc, etc. As they get even closer to ultimate failure, connections might show normal on a voltmeter (which requires almost no power to operate), but then break down the instant more of a load is applied to the circuit. When an electrical connection deteriorates to this condition, you could arrive at the end of a season with a particular connection working perfectly OK, but so close to breaking down that the additional corrosion which occurred during the preceding winter will have driven it over the edge and it will not let you start this season. Diagnosing a malfunctioning primary ignition circuit is not easy. Even if you quickly determine that the reason your engine isn't starting is due to lack of spark, identifying a faulty connection within the primary circuit as being the specific cause is complicated by the fact that engines will usually rotate to a stop with the points (or Ignitor) open after being shut down. This means that the primary circuit will be open between the coil and engine ground, and you would normally expect to read battery voltage between the positive terminal of the coil and engine ground. With voltmeters requiring so little electrical power to operate, you might well measure full battery voltage between the positive terminal of the coil and engine ground and assume that the primary circuit is OK. However, the instant the points (or an Ignitor) close the primary circuit, the current drawn by the coil will quickly cause a corroded terminal to break down, and the engine will not start. The best way to diagnose lack of a spark as being caused by a faulty connection within your primary ignition circuit is to manually rotate the engine with the ignition switch on while measuring voltage at the positive terminal of the coil. During this check you should observe the voltage varying between full battery voltage and approximately 10 volts as the primary circuit is energized and de-energized by the opening and closing of the points (four times for every revolution of the engine). To discover the actual location of a defective connection, rotate the engine until the points reopen and you're again able to measure battery voltage. Then ask a friend to hold a voltmeter between the positive terminal of the coil and engine ground while you tap all the connections within the primary circuit with the handle of a screwdriver (including the ignition switch). If you see the voltmeter flicker, you're undoubtedly tapping on the errant connection. 2) FUEL: A recent caller reported that during his spring start-up, his engine would start immediately on every try, but each time it would shut down after only 3 or 4 seconds. These symptoms are so consistent with an electric fuel pump not working that I'm sure I frustrated the caller by repeatedly asking him if he was absolutely sure that he had a mechanical fuel pump. After a lot of head scratching, the problem was determined to be air seeping through cracks in a weathered fuel line between the fuel tank and the inlet to the fuel pump. The incoming air was enough to maintain a small but continuous pocket of air in the top of the fuel in the sediment bowl. In this condition the pump was able to suck up only 3 or 4 seconds of fuel during cranking after which the engine shut down. As has been reported on so many similar troubleshooting scenarios, the fuel line had never manifested any sign of leaking or other suspicious behavior (reread “Fuel related shutdowns” at moyermarine.com for more on this important subject). 3) RODENTS: Look out for a chipmunk (or some other small critter) building a nest in your exhaust system. An engine will not usually “fire even a lick” if the exhaust system is fully blocked.