So all of a sudden my sled has extremely weak spark. I went to fire it up and it wouldn't start. I thought there was no spark at all but when I looked really close I could see tiny little sparks barely visible. Its got new plugs. I removed the flywheel, cleaned it up and inspected the stator. The stator seemed like two of the windings looked a bit burnt but when I looked at some photos online the others had sort of the same look. I tried testing the resistance on the coil packs but just kept getting funky reading (probably bad meter) but regardless all three are barely sparking. I am not sure what to check! I did a search but didn't really find an answer specific to weak spark. I recently installed a starter but it has started and run fine 3-4 times then all of a sudden bam. sparks almost gone. Any suggestions?
Extremely weak spark 98 Vmax 700
- Thread starter boutin73
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A couple of bucks
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Check your kill switch and if its OK you may have a wiring harness rub through. Search wiring harness rub through on the forum its a common problem and lots of info.
I am going to try testing the Stator tonight with a different meter. I have a suspicion it will be bad. Having said that, I contacted several online parts stores for the OEM and nobody has them in stock and need to be ordered from Japan. I can get an aftermarket on eBay but I am reluctant to. If I go OEM I might not get it before the season is done! Anybody had any experience with aftermarket like the SPI brand on eBay?
Lot of people had bad results with aftermarket stators on here.
I would stick with oem, I would rather have a used oem over a new aftermarket.
I would stick with oem, I would rather have a used oem over a new aftermarket.
I tested the stator and all three measurements came within range. I took it out to check connections and didn't see any issues. I'm going to put it back in. When I tested the coils however, I got consistent readings of 0.3 on two coils and 0.1 on the third. Specs say should be 0.05-0.07. This is between the primary leads. When measuring from the primary lead to the plug cap there's no reading at all. I even tested at the plug wire to rule out bad caps but got the same result. It seems extremely odd that all three could would go at the same time and still have similar readings between them. I'm at a loss and ready to start either throwing money and parts at it or quit! Any thoughts?
flywheel is rust free i hope.
Yup. First thing I did was clean it up. I bought a new meter and everything tests fine except the coils testing at 0.3 when manual says 0.05-0.07. But doesn't make sense they all died at the same time. I bought a used set of eBay since you can't buy new anymore. I also have new plug caps coming in. I'm at a loss....
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Yamahasrx700
Member
my Sx had the harness that runs across the steering gate rubbed though. I had to un rap the harness and found the main power to the ECM was grounding to the steering gate. I have had terrific luck with aftermarket stators. I think one issue is 1st to find out why the stator failed in the first place.
My stator is testing out fine with Ohm meter so I assume it hasn't failed, yet...
The coils however do not test right when testing between the primary leads. I can only assume I am doing something wrong because two test at 0.3 and one at 0.1 when they should all be 0.05-0.07. They couldn't have all gone bad at the same time and have the same readings. Also they ohm out fine from primary lead to the cap.
I looked over the wiring good but didn't find any bad spots. Other than what runs under the motor I checked them all.
I had a 97 that did similar. It would run great, then not run, usually if it started it was good till it heat soaked then would stop, but occasionally would act up when cold. New stator solves the problem. Mine tested fine cold but wouldn’t make power when warmed up.
I got some new coils in. When I went to try to start it I noticed smoke coming out fr under the dash. After quit a search I found the ground wire was burning up when turning over the starter. I pulled harness and replaced all the burnt parts. Hopefully I can get it all back in... Anyway what would cause that to happen? Must have something to do with the starting system since it only does it when turning the engine over. Not sure if this would have had any effect on the spark intensity. Thoughts?
bad/weak grounds make everything behave weird.