Hi,
Trying to repair my stator.
I know that the cdi, lead, cap and plug are all fine.
The stator tests bang on with the meter.
I had the stator off to replace earth (white) wire as i found a break in the cover, which could've led to it shorting on occasion.
I originally thought this stator was broken as the coils and laminates were loose on the backing plate, but the symptom was no spark and that doesn't quite add up. Either way its solid now, the earth lead is good, the pickup reads 110 and the LT coil reads 470 so both are fine.
the only other evidence i have is that when fitted, i get a shock when i hold the green and white, but no shock when i hold the red and white. Im sure thats a clue, but f@@k knows what it means.
The only thing i can think to do now is replace the pickup for a K2 item i have, although the pickup reads fine and is stronger than the spare i have.
any thoughts?
EDIT: its also definitely not an alignment issue as the flywheel and stator have worked together in the past.
fault finding stator (all readings perfect) SORTED! :)
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coaster
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A couple of points, the white wire is connected to earth so any missing insulation would not cause it the 'short'.
The LT coil produces a current building throughout each revolution of the flywheel which charges the capacitor inside the CDI. The pickup on the other hand just produces a short low voltage pulse at the firing point once per revolution which triggers the capacitor to dump its stored charge to the HT coil. Therefore it's entirely normal that you would get a tinglke from the Green but nothing on the red.
Did you check that the little earth tags on the stator are very tight and unable to move? a high resistance earth would not help matters.
Also check for high resistance in any connections between the stator and CDI and I'm assuming that you have checked for other ignition faults like HT lead, plug, cap and tried disconnecting the loom green from the CDI?
Colin
The LT coil produces a current building throughout each revolution of the flywheel which charges the capacitor inside the CDI. The pickup on the other hand just produces a short low voltage pulse at the firing point once per revolution which triggers the capacitor to dump its stored charge to the HT coil. Therefore it's entirely normal that you would get a tinglke from the Green but nothing on the red.
Did you check that the little earth tags on the stator are very tight and unable to move? a high resistance earth would not help matters.
Also check for high resistance in any connections between the stator and CDI and I'm assuming that you have checked for other ignition faults like HT lead, plug, cap and tried disconnecting the loom green from the CDI?
Colin
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olliewtf
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brilliant thats very helpful.
yes, ive tried loom green and plug cap lead etc.
I know the cdi is fine too.
when i check the earth to earth, white to mag, it reads high before it settles around .9. i think that's more down to my multimeter though.
i did check the earth tag. on this stator there is a tag, like a washer, sat underneath where the rivet is peaned over. this was able to move slightly, so i hammered the rivet a little until it was tight.
Im pretty sure there is a good earth contact. the readings suggest so, however, what i am concerned about is that the rivets dont travel the full length of the laminates to the other side, they have possibly sheared at some point. however there are 3 tapping screws holding everything together.
could it be that because the rivet is not as secure as it should be, it is causing high resistance stopping the unit to function correctly?
I know i shouldve sorted the rivets out but i have no idea where you get them from, how you fix them, and plus id have to drill out the existing ones as they are a tight fit, and i dont have a drill. I did ask my local scooter shop to do this for me but long story short they said no.
having said all that i went over the connections and tested them, and even though its not ideal im confident theyre okay. although i suppose there is no way to be sure and its best to just eliminate this.
cheers!
yes, ive tried loom green and plug cap lead etc.
I know the cdi is fine too.
when i check the earth to earth, white to mag, it reads high before it settles around .9. i think that's more down to my multimeter though.
i did check the earth tag. on this stator there is a tag, like a washer, sat underneath where the rivet is peaned over. this was able to move slightly, so i hammered the rivet a little until it was tight.
Im pretty sure there is a good earth contact. the readings suggest so, however, what i am concerned about is that the rivets dont travel the full length of the laminates to the other side, they have possibly sheared at some point. however there are 3 tapping screws holding everything together.
could it be that because the rivet is not as secure as it should be, it is causing high resistance stopping the unit to function correctly?
I know i shouldve sorted the rivets out but i have no idea where you get them from, how you fix them, and plus id have to drill out the existing ones as they are a tight fit, and i dont have a drill. I did ask my local scooter shop to do this for me but long story short they said no.
having said all that i went over the connections and tested them, and even though its not ideal im confident theyre okay. although i suppose there is no way to be sure and its best to just eliminate this.
cheers!
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olliewtf
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also if the lights flicker when kicking over would that not suggest that the earth tag is working? i noticed that the white wire and lighting coil share the same tag.....
and apologies it is evident im no electrician but i would love to be able to fix this!
and apologies it is evident im no electrician but i would love to be able to fix this!
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coaster
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Thecwhitecwire is only really a backup eart connection as the stator is bolted to the engine via the h
Mag housing but do make sure the earth from the casing to the fra me is good. Functioning lights is not a reliable sign that all is good in the eart dept as throttle, choke, clutch and gear cables wil provide an earth path albeit a poor one.
Colin
Mag housing but do make sure the earth from the casing to the fra me is good. Functioning lights is not a reliable sign that all is good in the eart dept as throttle, choke, clutch and gear cables wil provide an earth path albeit a poor one.
Colin
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Adam_Winstone
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I've had two different stators fail because of the thin wire that connects from back of LT coil to closest earth tag have a hairline break in it. In both cases you would get correct readings from the wires, however, when pushing against the back of the LT coil to test the connections with a mulitmeter, the connection would fail. At rest (no light pressure applied to back) the connection would give perfect readings. As I say, this has happened to 2 different stators of mine.
I resoldered the joints in question, then covered the joints in Araldite to avoid vibration fracture, and I've had perfect service from these since.
May not be your fault but worth a look.
Adam
I resoldered the joints in question, then covered the joints in Araldite to avoid vibration fracture, and I've had perfect service from these since.
May not be your fault but worth a look.
Adam
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olliewtf
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Cheers guys that's all sounding good. Someone on fb has informed me that 0. 9 is really too high a resistance. I thought anything under 1 was okay. Either way I'm going to sort the earth, and also inspect the LT coil. Having said that i got the same reading from the Indian stator, 0. 9, having said that it could also have had a dodgy earth. I'm just trying to factor I the possibility of a not very accurate multimeter.
Thanks again!
Thanks again!
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Grumpy225
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olliewtf wrote:Cheers guys that's all sounding good. Someone on fb has informed me that 0. 9 is really too high a resistance. I thought anything under 1 was okay. Either way I'm going to sort the earth, and also inspect the LT coil. Having said that i got the same reading from the Indian stator, 0. 9, having said that it could also have had a dodgy earth. I'm just trying to factor I the possibility of a not very accurate multimeter.
Thanks again!
Yeah that is too high. Just to check your meter put booth leads together and see what the ohm reading is. This way you have a good base line to compare to.
A decent meter will have a "Null" feature which allows the resistance of the leads to be "zeroed". Alternatively, as said, measure the resistance of the leads and subtract from the final reading. A flatish battery can also give false readings.
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olliewtf
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righto well according to that, the meter itself reads the same. .9. so where does that put me?
if the meter contacts together give me the same continuity reading as my earth point, surely then the earth checks out? that doesn't mean to say i wont address it, but surely the meter is now suggesting that it is after all okay, as long as it is not an intermittent failure?
if the meter contacts together give me the same continuity reading as my earth point, surely then the earth checks out? that doesn't mean to say i wont address it, but surely the meter is now suggesting that it is after all okay, as long as it is not an intermittent failure?