Logo
FULL SITE MENU

Evinrude ignition coil

L

lakewind

Member
My Evinrude 1978 4 hp model 4806e is producing a weak and intermittent spark on the #1 cylinder.It has electronic ignition.The power pack has been replaced after a mechanic told me it was bad but still no spark.Does anyone know the procedure for testing the ignition coil on this engine? Any help or advice would be appreciated.I had just got carburetor issues resolved on this engine and now this.
 
Swap coils if the problem stays the same you have two good coils. If it follows the coil the coil is bad. You really need a dva adaptor for your VOM to properly diagnose the stator and trigger if they test good the PP is bad. CDI electronics installation instructions gives you the specs.
 
You don't need any fancy equipment or complicated tests. All you need is common sense. Consider the facts:

1.There is ONE driver coil generating the electricity. It charges the power pack's internal capacitor to fire BOTH cylinders, alternately. So, if it charges the capacitor for one, it also charges it for the other.

2. There is ONE sensor for telling the powerpack when to fire, and which cylinder to fire it to. It determines which cylinder according to the polarity of the magnets passing by. Don't worry about the details, just believe that if it fires one way, it will fire the other way.

3. There is ONE powerpack containing that capacitor and two electronic switches, one for each cylinder. The electronic switches operate according the polarity from the sensor (above). Now, if one of those switches is not operating correctly, its associated cylinder will not have spark. You already told us the powerpack has been replaced. So, unless he put a defective one on there, let's assume it is OK.

4. That leaves---guess what? The coils. One for each cylinder. You know one is ok, and the other is questionable. It is reasonable to suspect that questionable one.

5. But don't stop there. There are a couple of wire connections that may be loose or corroded, or broken internally.

6. A multimeter can be used to check out the wires and/or the internal wire within the coil, and/or the spark plug wire.

7. Or, back to what was said in the first place---simply swap the coils. Or replace the suspect one if you don't mind spending money on something that might not be bad. Seems that method was already used on the powerpack.
 
As "Gator" sates... No fancy equipment needed! You can use the engine's own ignition system components to test the coils.

In your case, simple switch momentarily the orange wires leading from the powerpack to the coils. Now, with (for example), having the orange wire from #2 coil now connected to that #1 coil..... If #1 coil now has spark, then obviously it is good... still no spark, just as obviously bad.
 
Thank you all so much.I have a better understanding of how this engine works now.There are only a few outboard mechanics in my area and they really take advantage of their customers.One actually told me not to call him he would call me when he had time.I will try swapping coils.Will post results.
 
Basically we know the charge coil is good if you get spark on one cylinder. Swapping coils confirms both coils are good. You already swapped the pack that points to the trigger. Have you cleaned the connectors with electrical cleaner and putback together with dielectric grease. Sand all grounds metal to metal? It could be a dirty connection. Always check spark with a open air spark gap tester it must jump a 7/16 gap with a crisp blue snap.
 
No the trigger also fires both coils !!----There is only one trigger coil / sensor on that system as already explained !
 
Back
Top