IGNITION SYSTEM REPAIR TIPS

The subject of the outboard ignition system could fill a phone book! I will only try to give a general procedure to follow here, the variety of systems used is boggling to the mind. Keeps engineers busy I suppose.

The simplest system is the flywheel magneto. First thing to have handy to service this is the correct type of flywheel puller. All outboard flywheels are pulled from the center, under no circumstances attempt to remove a flywheel by use of a gear puller that hooks under the outside edge. You WILL ruin it!

Almost all ignition systems incorporate some sort of a stop switch. The FIRST test of any system is to simply disconnect this circuit AT THE SOURCE to determine if there is a simple short in the wiring or switches. On most new CDI systems this wire has been standardized as a black wire with a yellow stripe.

While we are on the subject of grounds, be sure all the coil, CDI pack and mounting bracket ground leads are clean and have continuity. If there's no ground, the system won't work.

On a magneto energized CDI system, take a visual look at the stator up under the flywheel. Is it leaking honeylike liquid potting compound onto the top of the block? Drips hanging off the coils? Cracks/burned spots? Even if the electrical values are on spec, a stator showing any of these symptoms is NO GOOD and must be replaced. This applies to any other potted component as well.

There is a definite relationship between the charging circuit and the ignition on all CD systems. It is IMPERATIVE that all battery connections be clean and tight. I recommend a marine type battery with threaded posts to accept your battery cables. Toss the wing nuts and use stainless steel elastic lock nuts. Mount excessive accessory leads on a separate terminal; many newer marine batteries have 2 on each side. Test the rectifier/regulator to be sure the system is charging. An inoperative charging system will cause an otherwise good stator to overheat causing it to fail.

WARNING! These systems carry up to 300VAC in the primary and some 45,000 in the secondary. Extreme caution is a MUST when servicing.

Perform all ignition coil and powerpack tests on an insulated or wooden bench top.

Do not handle CDI powerpack or ignition coil output leads during any type of output test.

Do not touch any of these leads when the engine is cranking or running.

Motor cover is a machinery guard. Use caution when conducting tests on a running engine.

BE CAREFUL. Other hazards may exist, you should be aware at all times.

IF you wish to service or repair your own ignition system, I HIGHLY RECOMMEND you obtain an OEM model-specific service manual to help you. We have most available RIGHT HERE at Mastertech.

Meanwhile, you can check out this PDF file for some general test procedures.