How do I test for power at the ignition coil on a 1998 Evinrude outboard?
I've got a 1998 Evinrude outboard that turns over but won't start. How do I check whether power is reaching the ignition coil, and should I get 12 volts there with the key switched on?
Answer
On most carburetted 1998 Evinrude outboards, the ignition coil receives a high-voltage pulse from the power pack as the engine turns, so a steady 12V supply with the key on is not expected. Check spark first, then measure the coil's primary feed during cranking with a suitable multimeter and a direct voltage adapter, usually called a DVA adaptor.
Identify the engine
Read the full model number on the transom bracket identification plate. Horsepower and year alone are not enough: Evinrude used several ignition arrangements. A 1998 Ficht direct-injection engine requires its own diagnostic procedure rather than the conventional power-pack tests below.
On a conventional capacitor-discharge ignition system, the stator supplies ignition energy and the timer base provides the firing signal. The power pack then sends pulses to the individual coils. The battery turns the starter; it does not normally supply the ignition coil directly.
- Check battery terminals, the engine earth cable and starter connections for looseness or corrosion.
- On electric-start models, measure voltage across the battery posts while cranking. If it drops below roughly 10V, check the battery and starter circuit before diagnosing the ignition.
- Inspect coil earth connections, mounting points, plug leads and connectors for corrosion, cracks or tracking marks.
Keep the engine in neutral and ventilate the area to clear petrol vapour. Keep hands and test leads clear of the flywheel and propeller during cranking.
Check for spark
Connect an adjustable, properly earthed ignition spark tester between the plug lead and a clean engine earth. A loose spark plug resting against painted metal gives unreliable results.
- Turn the key off before connecting the tester.
- Leave the stop-switch lanyard fitted and set the tester gap specified for your engine.
- Crank briefly and look for a consistent spark across the gap.
- Repeat on every cylinder and record which ones fail.
Many conventional OMC electronic ignition systems are tested across a 7/16in gap, approximately 11mm, but confirm the specification for your model. Keep disconnected plug leads attached to earthed testers; do not leave them arcing freely.
One dead cylinder points towards its plug, lead, coil or individual power-pack output. No spark on any cylinder suggests a shared fault, such as the stop circuit, stator, timer base, power pack or inadequate cranking speed.