wls
Member
I have a 78 ex 440, oval racer, when it runs it runs great. Started 3 races ago, spitting sputtering in final, driver had to flick throttle to finish 2nd, we thought it was a fuel issue, got home, drained gas, put fresh in w/drygas, cleaned carb, new fuel lines, new fuel filter in tank, w/new line, new mikuni pump, new vacumn line. 2nd race run hot laps, quit duing hot laps, we figured run till she blows, in heat race got hit in turn 1/2, lost a lap,got started was running good picking off sleds, got to final, every one went. In final, got 2 laps quit, towed to pits. Checked for spark, very weak at the best, actually I think only one had weak spark. Started up when got back home, 1.5 hours later. so figured electrics wanted a reason to get a hewelt cdi, got that and also new ex coils, also replaced teather. 3rd race, run hot laps quit. But in the heat, very fast, took 2nd, lead for 1/2 lap. Final we got another 1.5 laps, quit like turning key off. So all along figured something may be wrong in stator area, got it out, put spare in, found out one of the source coils are bad, took orginal stator to yamaha dealer, everything checked out, little low on one thing, but within spec, unless when it gets warm something fails. Also we eliminated the key switck, checked with a ohm meter for cracked lines from the stator hookups to the cdi hookups, we also switched cdis, nothing. I do have 2 internal coils coming for it, wonder if I should also replace the source/pulser coils?
Any ideas
Wanted to add, the new cdi, says to run non-resister plugs, so I got some plugs and also caps, but have'nt try it yet, waiting for new internal coils.
Any ideas
Wanted to add, the new cdi, says to run non-resister plugs, so I got some plugs and also caps, but have'nt try it yet, waiting for new internal coils.
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