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| Spring Maintenance |
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| 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 or call Ken at our phone parts line, 610-421-4436. |
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.
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This is the time of year many of us have been longing for. The time when approximately half of the 20,000 Atomic 4s estimated to be in active service will emerge from a winter lay-up. After spring commissioning, these engines will once again become vehicles of re-creation for their owners. As you might expect, we at MMI also look to this season as a time of renewal and try to make every spring a positive experience for our customers. Here are four simple checks which history has taught us will pay the biggest dividends for the time spent during this very busy time.
Pre-start checks: (all accomplished with the raw water through-hull closed):
1) OIL: Check oil and replace as necessary.
2) COMPRESSION: Remove all spark plugs and hold your thumb over each spark plug hole while turning the engine over a couple seconds. As long as compression is sufficient to force past your thumb no matter how hard you press, the compression is OK (80 psi or above). If any of the valves show signs of sticking (noticeably poorer compression), a few squirts of Marvel Mystery Oil will usually help those cylinders back to life.
3) IGNITION: While plugs are removed, check them for condition and replace them if they have carbon deposits (especially if the carbon is oily). If you have conventional ignition (points, condenser, rotor), rub a small piece of match book cover between the points to clean them. Then remove the coil lead from the center of the distributor cap and hold it 1/4” from the head or block while turning the engine over. Check for a strong secondary arc which can be stretched to at least 3/8”. Note: linked products above are for late model motors, see early model section for corresponding parts.
4) FUEL: With clean filters (primary and secondary), carefully remove the main passage plug or bowl drain from the carburetor and pump enough fuel through the system and into a clean glass jar to insure perfectly clean fuel. Reinstall the main passage plug or bowl drain and pump for an additional 5 or 10 seconds to re-prime the carburetor. The priming lever on mechanical pumps can be used in this step.
Electric fuel pumps will need to have a jumper wire installed across the oil safety switch so the pump will run by turning on the ignition switch. In electric fuel pump systems, it's very convenient to install a second electric pump upstream from the primary filter with a manual switch to use in this step. The second pump can also serve as an emergency back-up in case the primary fuel pump fails.
NOTE: One of the more useful side effects of 10% ethanol fuel is that it dissolves varnish build-up within older fuel systems. If you discover orange colored crud moving through your fuel system, repeat the above step and be prepared to check and replace filters several times during the season. In most cases, varnish build-up will be completely removed after several additional filter changes.
For the first start of the season, we recommend keeping the raw water through-hull valve closed until the engine starts in order to avoid any possibility of water flowing back into the exhaust manifold should the engine prove to be a bit hard starting. In fact, if you know that your particular exhaust system is problematic in terms of allowing water to flow back into the exhaust manifold, it makes sense to follow this suggestion permanently.
Hoping the 2012 season will be the best ever for you and your sailing companions,
Don Moyer
| SUGGESTED SPARE PARTS AND TOOLS FOR CRUISING |
The following items should only be considered as a starting point in devising a list of spare parts and tools. Please add or subtract from the list as appropriate in meeting your specific needs. Remember; your best assurance against being caught in a threatening situation (or working your way out of one), depends not only on the spare parts that you might have on board, but on a thorough understanding of the different systems in your engine.
SPARE PARTS:
1) Coil.
2) Four new spark plugs.
3) Spare fuel pump.
4) Spare water pump (a spare impeller may suffice if no snap ring is required, and the pump is less than 5 seasons old, or has less than 500 operating hours).
5) Three or four feet of engine water hose, fuel line (with appropriate sized hose clamps), and a small roll of electrical wire (12 or 14 gauge).
6) A roll of good quality electrical tape.
7) Spare filter elements for any filters you have on board.
8) Spare fuses.
9) Alternator belt
10) Spare alternator (optional).
RECOMMENDED TOOLS (In addition to "normal hand tools"). Be sure to add any tools that would be needed to install any spare parts that you might add to the above list.
1) A small digital volt/ohm meter.
2) A three-foot length of 14 gauge wire with a ring terminal on one end, and a clip on the other. This wire can be used to "hot wire" the ignition system in the event of a failure of the primary circuit within the boat's electrical system.
3) Electrical crimping tool and a small supply of ring terminals, butt splices, etc.
4) Remote starter switch (available for about $30 at most auto parts stores).
5) A 12 volt light with alligator clips to use for checking continuity.
6) MMI Service and Overhaul Manual
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