Spark or No Spark?

[SusieQ 21]

I have a 1996 Evinrude 150 hp 60 degree (Looper) engine. Simple question: OMC manual states that output test Ignition spark should arc 7/16”.on spark tester. If spark will only jump 3/8” on spark tester on port bank cylinders and no spark on starboard bank cylinders, in accordance with the manual’s “troubleshooting sequence chart” should that be considered “No Spark on Any Cylinder” or “No Spark on Three Cylinders?”
And yes, I have performed the "shift switch test" and achieved the following result: Full 7/16” arc on port bank cylinders and weak 3/8” spark on starboard bank cylinders. Stator voltage output test indicated bad ground or stator, yet resistance tests are within limits. Stator is new. Removed stator and saw no issues or potential grounding issues.

 

[cyclops222]

Tried the correct, brand new sparkplugs ? Adjusted to the correct gap ? Are the old plugs looking brand new ?

 

[racerone]

What is the motor doing / not doing ?

 

[cyclops222]

Look into his past posts over the years. RIP

 

[saltchuckmatt]

What brand of stator?

 

[SusieQ 21]

Tried the correct, brand new sparkplugs ? Adjusted to the correct gap ? Are the old plugs looking brand new ?

Champions QL78YC brand new set to .030” gap. Even tried two different sets of new plugs. Also installed new (gray) Evinrude plug wires. New coils, new power pack, new regulator/rectifier, new optical sensor, new stator, new (used) flywheel. Used Evinrude / BRM parts when available.

 

[SusieQ 21]

Look into his past posts over the years. RIP

Have done that for past 3 years. Looking for SPECIFIC response to my query regarding spark arc length That is: is a 3/8” arc considered NO SPARK in reference to the ‘Troubleshooting Sequence Cart,” especially in consideration that the manual specifies a 7/16” arc. If interested, please refer to initial post. Thankyou.

 

[SusieQ 21]

What brand of stator?

New CDI Electronics. The old was fried. Also replaced (damaged) original flywheel. Yes, it’s the correct (60 deg Looper) flywheel.

 

[SusieQ 21]

What is the motor doing / not doing ?

Thanks for your question.
Currently, the motor won’t run, but will fire on starting fluid…..not on fuel mixture….sprayed into carb throats. Long story short, thinking I have overlooked something or simply messed-up along the way, I decided to re-initiate troubleshooting sequence from the beginning (AGAIN). That said, I have fully charged batteries and engine seems to be cranking adequately, although I have not measured RPM, since my onboard tach doesn’t work.

I have 3/8" spark arc on all (3) port bank cylinders, and no spark on starboard bank cylinders. Isolating the shift switch produced 7/16” arc on port bank cylinders and 3/8” arc on starboard cylinders. Clearly, neither condition meets output test. Also measured voltage from stator which failed to meet specs, but resistance tests were good. Removed / inspected the recently installed (new) stator and found nothing suspicious. Visually checked for grounding at stator wiring to power pack, including connectors, and saw nothing suspicious.

 

[SusieQ 21]

Look into his past posts over the years. RIP

Btw, I guess I misunderstood the intent of your message….”RIP.” Please explain.

 

[Crosbyman]

the motor won’t run, but will fire on starting fluid…..not on fuel mixture….sprayed into carb throats.

so why doesn't fuel reach the cylinders if it fires up on starting fluid..

I read lots of electrical.. .work... what about carb work ??? are they full of fuel mix ??

 

[SusieQ 21]

so why doesn't fuel reach the cylinders if it fires up on starting fluid

but will fire on starting fluid…..not on fuel mixture

so why doesn't fuel reach the cylinders if it fires up on starting fluid

but will fire on starting fluid…..not on fuel mixture

That’s what I’m trying to determine.
I believe fuel is reaching cylinders, since, at times, the plugs get wet if I use enrichment too frequently. Btw, enrichment valve has been rebuilt with new seals and is operating.
My question is: Will a weak spark fire the engine on fuel, and/or why the spark doesn’t meet specs. Could be two problems (ignition and fuel) occurring; regardless, need to be certain spark is adequate.

 

[SusieQ 21]

the motor won’t run, but will fire on starting fluid…..not on fuel mixture….sprayed into carb throats.

so why doesn't fuel reach the cylinders if it fires up on starting fluid..

I read lots of electrical.. .work... what about carb work ??? are they full of fuel mix ??

Thanks for your comments.
Carbs rebuilt 3X using Evinrude kits with correct (brown) seals. Used denatured alcohol, syringes, carb wire, and light air pressure to clean all orifices. Replaced fuel bowls with new ones. Added fender washer to side covers to help assure flat / even mating surfaces. Float drops set to manual specs. Also installed new throttle body and intake manifold gaskets. Leaf valves appeared to be in excellent condition.
Carb fuel bowls fill with fresh fuel mix from new accessory fuel container. New fuel lines, filter, and primer bulb. Carbs are getting fuel.
Really hate to start replacing electrical components (e.g., stator) without knowing for certain the new replacements are bad. Way too much $$ and effort in this project already. Gun shy, I guess. That’s why I’m making a last ditch effort, starting from scratch!

 

[flyingscott]

Check your shift interrupter switch. You need to do a dva test and test the stator. should easily jump a 7/16" gap

 

[SusieQ 21]

I did. See my initial post. I isolated the shift switch. I also removed the switch to check operation (possible sticking).

 

[flyingscott]

do the rest of the tests.

 

[SusieQ 21]

do the rest of the tests.

In the process of doing just that. That said, a couple questions.
Charging circuit from stator failed, but passed resistance tests. Since stator is new, I removed and looked for grounding issues in stator and wiring / connectors. Found nothing. Is stator bad? New stator is $400. Hate to be wrong AGAIN. Where to look for grounding issues? Could (new) ignition key / related wiring be contributory to grounding issues. FYI, the ignition key produces same results as remote (push button) starter.
Is 3/8” Spark considered “No Spark” by virtue of manual specified 7/16” spark?

 

[saltchuckmatt]

I know an ex-professional Evinrude dealer/mechanic who now sells Mercury and is about to retire who said he always had bad luck with cdi stuff so he stopped buying them.

You say your stator failed regarding the charge system. Something is causing the spark not to jump enough.

Is that proof? No, but it points to issues with that component.

To answer your question, if the spark doesn't meet speck is that considered a failure. In my book yes.

Personally I just replace some ignition coils this summer that met spec including the spark jump test. Motor started better and idled better.

To rule out other things, have you tried starting it with the remote control unplugged at the motor? Or at least the spark jump test.

You have improved spark when you disconnect the switch so you may have multiple issues.

Everyone can sense frustration from you so the only thing I can suggest is carry on. You definitely have persistence.

 

[racerone]

Inspect and load test the 12 volt battery.

 

[SusieQ 21]

Inspect and load test the 12 volt battery.

I run two batteries. Both batteries are continually kept fully charged on “Battery Tender” maintenance chargers. I shall load test both batteries.
Thank you.