Possible Ignition coil failure mariner 40hp

[PatrickMonahan]

have many of the symptoms of a failing ignition coil, it is a dual coil, wet spark plugs, misfiring, power loss, engine turning off, using alot of petrol and stuttering at high rpms, here is the ignition coils and wires, i dont know whether they are installed correctly but since it runs they probably are

 

[PatrickMonahan]

No Title

 

[Faztbullet]

This is NOT a dual coil motor it is a single coil motor(lost spark) as it fires both cylinders at same time. Check coil to see it its in ohm spec's first then test lighting coil.

 

[PatrickMonahan]

I have measured the primary circuit in the coil as 0.6 OHMS, DOES ANYBODY KNOW WHETHER THIS IS IN THE RIGHT RANGE??

 

[PatrickMonahan]

I seem to be not able to get any reading from the secondary circuit, would the engine run badly on the primary circuit alone and stutter at high rpms, also I got a shock from the top spark plug lead on the top cylinder, would this have a negative effect on the spark?

 

[Faztbullet]

Primary is .08-.10 and secondary is 3000-4100. If it has the black hard resistor caps take them off and ohm them too.,should be about 5 kilohms

 

[PatrickMonahan]

would the engine run with no resistance on the secondary coil, i tested it again this morning and got nothing, also the engine never turned itself off untill the past 2 times i went boating, could this be attributed to a degradation of the coil, a slow stall after trying to go flat out as its stutters down the river trying to rev high, still don't understand why i cant get any resistance reading from the secondary coil and it still runs, confused, either fuel or electrics or air

 

[PatrickMonahan]

Engine spark idling

 

[PatrickMonahan]

Idling speed

 

[PatrickMonahan]

would the engine run with no resistance on the secondary coil, i tested it again this morning and got nothing, also the engine never turned itself off untill the past 2 times i went boating, could this be attributed to a degradation of the coil, a slow stall after trying to go flat out as its stutters down the river trying to rev high, still don't understand why i cant get any resistance reading from the secondary coil and it still runs, confused, either fuel or electrics or air, measured around 190volts coming from cdi, it was very variable, changing from 160 to 190, is that suppose to happen?

 

[PatrickMonahan]

ran the engine on one cylinder at 1400rpms, anything less than that and it would turn off, changed them around and pulled plug off again and it ran, i got a shock from the spark plug wire coming out of the ignition coil? is this a probem? would this cause the engine to stutter at high rpms?

 

[Faztbullet]

Get rid of that neon tester and get a proper gap tester. You need to observe the actual spark and see if it is blue and has strength to jump proper gap.

 

[PatrickMonahan]

Measured the volts coming from the cdi unit (pack) today and it was producing between 160-190 volts and I read that it should be producing 210 volts minimum from this part, would this cause problems

 

[PatrickMonahan]

Very varied 160 to 190 changing in milisecond's, as well tested secondary circuit on ignition coil and got absolutely nothing, no resistance which is another problem, may buy a new coil

 

[Faztbullet]

Check the actual (visual)spark as a coil is nothing but a step up transformer. If you have weak voltage from charge coil(under flywheel) to switchbox/CDI you will have weak spark out to plugs. You need to find a spec for DVA voltage from charge coil under flywheel to CDI/switchbox.

 

[DavidMoore]

It's only a problem if you get shocked twice from the plug leads, and the problem is not with the engine.:lol:

 

[PatrickMonahan]

Ordered a new ignition coil since I couldn't get a resistance reading from the secondary circuit, hopefully this will help, the engine started to misfire at 2000rpm down the river the last time I brought it down

 

[PatrickMonahan]

And stopped completely after 10-15mins of driving around

 

[PatrickMonahan]

Tested between the white red trigger wire and black wire coming from flywheel and i got 15.1 ohms resistance and the recommended range is between 12-16 ohms so this is fine, the brown stator wire had no resistance which was red from the brown stator wire to black engine ground and i got a flicker of a number e.g. 68 ohms and then it vanished from the screen, its supposed to be between 125 and 145 ohms but only comes up monetarily on the screen, anyone know what this means?

 

[PatrickMonahan]

Does anybody know would a shorted secondary coil cause stuttering at high res and stalling after 10 to 15 mins of driving around because my secondary coil doesn't read any ohms so, the spark must be jumping a gap in the coil and what would that do inside the coil? Checked the stator trigger and cdi and they are within parameters so the only thing that was wrong is the secondary coil that is probably shorted inside, I hope the cdi is not damaged