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Cos Misfire.... Burning out rotor arms?

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Old 14-02-2011, 08:11 PM
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Bloomers
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Default Cos Misfire.... Burning out rotor arms?

still chasing the mis on my car, and i've noticed that my rotor arm has started burning out. i replaced it about 2-3k miles ago, as the last one was fucked, just surprised this one has gone the same way so quickly.

any ideas whats causing it? want to keep her running as smooth as i can till i get the rest of the bits i need for wasted spark.

i'm running a grp a coil, magnecor leads and 071, gapped to .7-.8 (can't remember which

cheers
Old 15-02-2011, 01:03 PM
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davy 6457
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having same problem as you!! burnt rotor arm and cap,mine is causing a miss high up the range. as you i have group a coil and 071's although i gapped mine to 0.6.you havent tried replacing the cap at the same time as the arm have you?
Old 15-02-2011, 02:15 PM
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cossie891
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Mine was the same but it went boom before I fixed it
Old 15-02-2011, 05:59 PM
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wulliesxr4i
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mines has a miss sumtyms wen its under load high up the revs then sumtyms is fine for weeks changed nearly every thing but its still the same so waisted spark is next on the list
Old 15-02-2011, 06:51 PM
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tabetha
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.7 to .8 is very wide, especially if running higher boosts.
There only needs to be a gap so the lecky can jump, big gaps do nothing power wise, the reason big gaps are associated with coilpack is simply when lean burn tech came out a stronger spark was needed to ignite the harder to ignite weaker mixtures, this was achieved with bigger gaps/better coils.
Try dropping to 0.5mm gap, any resistance to the spark occuring such as a big gap and higher boost will put strain on other parts, as lecky is lazy it will seek the easiest way out, this can be through the rotor arm(arcing) and other things.
Using precious metal plugs like IK27 etc helps massively in this respect, as they fire so much easier.
tabetha
Old 15-02-2011, 09:09 PM
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Bloomers
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I'll have a go tomorrow, tabs. i dropped them to 0.7 tonight, and it seemed to help a little. sometimes it decides to run fine, though, so will see tomorrow

davy, new cap with the arm.
Old 15-02-2011, 09:25 PM
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bruny
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my brother had a dutton kit car once and his was blowing rotor arms alot,took it to a garage and they said the timing was out abit and the wire terminals to the dizzy was full of dirt and oil,he sorted these problems out for him and car ran like a dream,
Old 15-02-2011, 09:58 PM
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Bloomers
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good call. will go over all the marks and terminals. probably something small thats making a big difference
Old 19-02-2011, 10:41 AM
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Paul_RS
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Could also be your wiring loom starting to die
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