Coil pack testing question

Technical aspects of automobiles, et. al., post #21,570
Author:
Date:
Subject:
 Mike Romain
 2008-07-16 09:43:06
 Coil pack testing question
I know this coil pack isn't off a car, it is off a Johnson outboard, but
thought maybe some of you knowledgeable folks might know how to test it.

It is for my sister-in-law's boat that my wife and I get to borrow so I
am trying to repair it for her.

The engine is a 2002 9.9 hp 4 stroke Johnson, Model J10TE4ST, with a two
cylinder coil pack. I believe the Johnson and Evinrude engine has the
same coil.

It will start and idle OK, but has no throttle response when the rpm
come up.

This coil only appears to put out one spark on one side, the top
cylinder. The bottom cylinder doesn't fire and the plug is wet with
gas. I put in new plugs and not a mark on it when the top one showed
clear heat marks. I swapped the plugs, same deal. The coil wires are
solid core and both of them and their 10K spark plug caps test OK with
my multimeter.

I have looked with google and can't seem to locate any resistance type
of tests for this kind of coil.

If anyone has any specs for it, I would sure appreciate them so I can
troubleshoot this engine a bit more.

The coil runs $130.00 and the brain box or module to run the coil costs
about $600.00.

Thanks,

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
'New' frame in the works for '08. Some Canadian Bush Trip and Build
Photos: http://mikeromainjeeptrips.shutterfly.com
Author:
Date:
Subject:
 Calab
 2008-07-16 14:39:41
 Re: Coil pack testing question
| This coil only appears to put out one spark on one side, the top
| cylinder. The bottom cylinder doesn't fire and the plug is wet with
| gas. I put in new plugs and not a mark on it when the top one showed
| clear heat marks. I swapped the plugs, same deal. The coil wires are
| solid core and both of them and their 10K spark plug caps test OK with
| my multimeter.

Dumb question...

Have you swapped the wires between the two plugs to make sure that's not
causing the "no spark"?

I assume that this is a single pack, so you can't swap coils around to see
if the spark moves to the other plug, eh?
Author:
Date:
Subject:
 Mike Romain
 2008-07-16 11:15:24
 Re: Coil pack testing question
Calab wrote:
> | This coil only appears to put out one spark on one side, the top
> | cylinder. The bottom cylinder doesn't fire and the plug is wet with
> | gas. I put in new plugs and not a mark on it when the top one showed
> | clear heat marks. I swapped the plugs, same deal. The coil wires are
> | solid core and both of them and their 10K spark plug caps test OK with
> | my multimeter.
>
> Dumb question...
>
> Have you swapped the wires between the two plugs to make sure that's not
> causing the "no spark"?
>
> I assume that this is a single pack, so you can't swap coils around to see
> if the spark moves to the other plug, eh?
>
>

Yes, the wires are stranded solid copper which very seldom fails. The
10K resistor caps test out OK also.

It is a single coil pack.

I also tried running it with the coil pack in the air in case it had
'tunneled' a ground. That made no difference.

Mike
Author:
Date:
Subject:
 W. Stief
 2008-07-16 20:24:00
 Re: Coil pack testing question
Mike Romain wrote:
> Calab wrote:
>>> This coil only appears to put out one spark on one side, the top
>>> cylinder. The bottom cylinder doesn't fire and the plug is wet with
>>> gas. I put in new plugs and not a mark on it when the top one
>>> showed clear heat marks. I swapped the plugs, same deal. The coil
>>> wires are solid core and both of them and their 10K spark plug caps
>>> test OK with my multimeter.
>>
>> Dumb question...
>>
>> Have you swapped the wires between the two plugs to make sure that's
>> not causing the "no spark"?
>>
>> I assume that this is a single pack, so you can't swap coils around
>> to see if the spark moves to the other plug, eh?
>>
>>
>
> Yes, the wires are stranded solid copper which very seldom fails. The
> 10K resistor caps test out OK also.
>
> It is a single coil pack.
>
> I also tried running it with the coil pack in the air in case it had
> 'tunneled' a ground. That made no difference.
>
> Mike

Time for a compression test.
Author:
Date:
Subject:
 Mike Romain
 2008-07-17 10:00:30
 Re: Coil pack testing question
W. Stief wrote:
> Mike Romain wrote:
>> Calab wrote:
>>>> This coil only appears to put out one spark on one side, the top
>>>> cylinder. The bottom cylinder doesn't fire and the plug is wet with
>>>> gas. I put in new plugs and not a mark on it when the top one
>>>> showed clear heat marks. I swapped the plugs, same deal. The coil
>>>> wires are solid core and both of them and their 10K spark plug caps
>>>> test OK with my multimeter.
>>> Dumb question...
>>>
>>> Have you swapped the wires between the two plugs to make sure that's
>>> not causing the "no spark"?
>>>
>>> I assume that this is a single pack, so you can't swap coils around
>>> to see if the spark moves to the other plug, eh?
>>>
>>>
>> Yes, the wires are stranded solid copper which very seldom fails. The
>> 10K resistor caps test out OK also.
>>
>> It is a single coil pack.
>>
>> I also tried running it with the coil pack in the air in case it had
>> 'tunneled' a ground. That made no difference.
>>
>> Mike
>
> Time for a compression test.
>
>

Unfortunately I wasn't expecting to work on engines so I didn't have my
tool kit with me for spark and compression tests.

The engine doesn't have a lot of hours on it. It wasn't blowing any
smoke at all and the oil was perfectly clear so I really hope is isn't a
blown cylinder. That would be kinda odd on a 4 stroke wouldn't it?

Mike
Author:
Date:
Subject:
 Pete C.
 2008-07-17 09:25:07
 Re: Coil pack testing question
Mike Romain wrote:
>
> W. Stief wrote:
> > Mike Romain wrote:
> >> Calab wrote:
> >>>> This coil only appears to put out one spark on one side, the top
> >>>> cylinder. The bottom cylinder doesn't fire and the plug is wet with
> >>>> gas. I put in new plugs and not a mark on it when the top one
> >>>> showed clear heat marks. I swapped the plugs, same deal. The coil
> >>>> wires are solid core and both of them and their 10K spark plug caps
> >>>> test OK with my multimeter.
> >>> Dumb question...
> >>>
> >>> Have you swapped the wires between the two plugs to make sure that's
> >>> not causing the "no spark"?
> >>>
> >>> I assume that this is a single pack, so you can't swap coils around
> >>> to see if the spark moves to the other plug, eh?
> >>>
> >>>
> >> Yes, the wires are stranded solid copper which very seldom fails. The
> >> 10K resistor caps test out OK also.
> >>
> >> It is a single coil pack.
> >>
> >> I also tried running it with the coil pack in the air in case it had
> >> 'tunneled' a ground. That made no difference.
> >>
> >> Mike
> >
> > Time for a compression test.
> >
> >
>
> Unfortunately I wasn't expecting to work on engines so I didn't have my
> tool kit with me for spark and compression tests.
>
> The engine doesn't have a lot of hours on it. It wasn't blowing any
> smoke at all and the oil was perfectly clear so I really hope is isn't a
> blown cylinder. That would be kinda odd on a 4 stroke wouldn't it?
>
> Mike

If swapping the leads between plugs moves the no-spark to the other one,
that should certainly eliminate any possible cylinder problem. I'm
presuming this is the "waste spark" setup where both plugs are fired at
the same time, with one wasted on the cylinder on it's exhaust stroke.
Author:
Date:
Subject:
 lugnut
 2008-07-17 10:56:33
 Re: Coil pack testing question
On Thu, 17 Jul 2008 10:00:30 -0400, Mike Romain
<[email protected]> wrote:

>W. Stief wrote:
>> Mike Romain wrote:
>>> Calab wrote:
>>>>> This coil only appears to put out one spark on one side, the top
>>>>> cylinder. The bottom cylinder doesn't fire and the plug is wet with
>>>>> gas. I put in new plugs and not a mark on it when the top one
>>>>> showed clear heat marks. I swapped the plugs, same deal. The coil
>>>>> wires are solid core and both of them and their 10K spark plug caps
>>>>> test OK with my multimeter.
>>>> Dumb question...
>>>>
>>>> Have you swapped the wires between the two plugs to make sure that's
>>>> not causing the "no spark"?
>>>>
>>>> I assume that this is a single pack, so you can't swap coils around
>>>> to see if the spark moves to the other plug, eh?
>>>>
>>>>
>>> Yes, the wires are stranded solid copper which very seldom fails. The
>>> 10K resistor caps test out OK also.
>>>
>>> It is a single coil pack.
>>>
>>> I also tried running it with the coil pack in the air in case it had
>>> 'tunneled' a ground. That made no difference.
>>>
>>> Mike
>>
>> Time for a compression test.
>>
>>
>
>Unfortunately I wasn't expecting to work on engines so I didn't have my
>tool kit with me for spark and compression tests.
>
>The engine doesn't have a lot of hours on it. It wasn't blowing any
>smoke at all and the oil was perfectly clear so I really hope is isn't a
>blown cylinder. That would be kinda odd on a 4 stroke wouldn't it?
>
>Mike


If it is a waste spark system and you swap the wires between
cylinders and it still runs the same, that would indicate
either a bad plug or a cylinder compression problem if you
know it is getting fuel. Swapping the plugs would isolate
the plug problem if that is the case.

Lugnut