'85 90hp Johnny J90 TLCOS loosing spark one side

tashasdaddy

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swapped power packs both loose spark on port side, thinking sensor pick up. motor runs 30 seconds then looses spark.
 

tashasdaddy

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Re: '85 90hp Johnny J90 TLCOS loosing spark one side

^^^^^^
 

tashasdaddy

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Re: '85 90hp Johnny J90 TLCOS loosing spark one side

^^^^^^
 

kenmyfam

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Re: '85 90hp Johnny J90 TLCOS loosing spark one side

How soon after it loses spark will it get spark again ???
Losing it as it warms up maybe. Coming back when things cool down. Malfunctioning pick up could be it.
 

tashasdaddy

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Re: '85 90hp Johnny J90 TLCOS loosing spark one side

has to cool and comes back 10 minutes.
 

emdsapmgr

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Re: '85 90hp Johnny J90 TLCOS loosing spark one side

Tas, Unlikely that it is the pack, so the other two concerns is the timer base or the stator. The good thing here is that both of them can be checked with the peak-reading voltmeter. That usually is enough to condemn one or the other. My experience is that if the stator gets weak, that it can cause intermittent misfires on all cyls, sort of a random fashion experienced during running. A constant problem one side would lead me to check cranking voltage produced by the timer base first. In a really odd, unusual case, I have seen the flywheel center magnets loose some of their magnetivity, causing poor ignition. A replacement flywheel solved the problem. You can keep my posted on your results at( saved your email address). Harley
 

kenmyfam

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Re: '85 90hp Johnny J90 TLCOS loosing spark one side

Certainly sounds like it's losing the spark as things warm and expand. Pick up still makes sense. Heading to work right now and will be on the road a lot of the day. I will keep thinking on this and check back in when I get a chance.
 

F_R

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Re: '85 90hp Johnny J90 TLCOS loosing spark one side

I sort of agree, timer/sensor assembly. But I could be wrong. Have been before.
 

tashasdaddy

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Re: '85 90hp Johnny J90 TLCOS loosing spark one side

so have i, why i wanted other opinions, put a bid on one ebay.
 

kenmyfam

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Re: '85 90hp Johnny J90 TLCOS loosing spark one side

Well, I have been on the road most of the day and am still with the sensor as the others are.
Time for a beer !!!!
 
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