help me trace down my no spark condition.. 74 z50

S

silverz50

New Member
ok guys i have a new stator points plug etc..

trying to get down to the problem

now for those of u that know the z50 wiring(no battery model)

from the flywheel is there is wires used

black and red..

red going to the lights and black for ignition..

my understand is that the black should give 6v AC current to the coil. when the ign switch is off it make ground to the coil and shutting it off..

so if i understand this correct if i take my tester of ac setting the black and red wire should give me 6v when i crank the motor..

right now when i tried this i dont get that on the black and i get 1.8v on the red
 
8

87Nassaublue

Member
Well for no spark, forget about the red stator wire. Your concerned with black wire only. Disconnect the stator plug from the coil plug. Connect the red lead of your meter to your black Stator wire. Connect the other lead of your meter to the frame/ground. When you kick the engine over, you should get and ac voltage (actually a pulsing DC) that approaches 6 volts, however, I would measure it using the dc range. It should ramp up to close to 6 volts. You'll see the meter reading ramp up. You won't get an AC reading of 6 vac if I'm not mistaken.
 
8

87Nassaublue

Member
If your getting no voltage at all, it sounds like you have your points wire installed incorrectly and it's grounding out your circuit. Look closely at the wire connecting to your point and make sure it's not connected directly to ground.
 
motodevo

motodevo

Active Member
Firstly get another plug, i've had new plugs that are duds, and spent hours testing everything else only to relise it was only this. Now you wont get 6v dc at kick over speeds on the black, more like 2v or less. As long as you get something on the black when disconnected from loom your off to a good start, then get a couple of feet of wire, crimp a female spade terminal on one end and plug it in to the male spade for the black wire coming from the motor then strip an inch of insulation off the other end wrap it around the bullet connection on the wire coming from the coil and then wrap it with electrical tape. Make sure the coil bolts are tight to provide a good ground.. Kick it over and see if you've got spark.Got spark then there is a problem with your loom, could be a short to earth on the black wire, could be a faulty killswitch or ignition switch, or the battery plug may be missing as this has a loop in it and if its not there the power from the black never gets to the coil. No spark take out the coil then get yourself a 6v lantern battery and some scrap wire, run a piece of scrap from the + terminal to the wire from the coil, then take two pieces of scrap and attach both to the - terminal and with the other ends attach one to the bolt hole on the coil and the other tap it momentarily on the thread of the spark plug, if it sparks the coil is good, if not check the spark plug cap for corrosion and continuity, if cap is okay coil stuffed. If coil is ok then its down to point and condensor.
 
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S

silverz50

New Member
wonderful info thanks alot

my wiring is all new everything confirm with my meter for connection.. ign switch etc.

so going to the spark plug are . i do have a new plug and i confirmed it works becuase i have a champion spark plug testing machiine.. when i start the unit up it makes the plug spark so thats all good ..

so back to the bike

after knowing the plug and new ngk cap plug is good the next was the coil.. now this coil was replaced about 6years ago and looks like new..

now b4 i go spending money on a new one i thought to confirm my stator area.

so i added all new stator with new condensor and points..

i have the stator with 2 .one for ignition and one for lights

i did a clean install soldered the 3 wires to condensor.. proper grounds.
set the new points to spec.

so i did try the 6v light bulb test directly to the 4 pin plug coming from flywheel.

the red wire for the lights does light up my test bulb when i crank it over.

the black does not (going from black wire and then other meter wire touched to ground by the coil)

so right there i stopped thinking about the coil etc for now..

so i think its safe to say the condensor is ok if the red wire lights up the bulb when i crank the motor.. ?

so now if u all agree its either the stator or something with my points

question for that when should the points be closed?
 
8

87Nassaublue

Member
I still think there is something up with your points or condensor. Its unlikely your stator and probably not the condensor. The condensor is just a capacitor. It's job is to bleed off some of the surge current so the points don't get burned. If it's shorted, (zero reading with an ohms meter) that will be your problem. If you have that points wire I mentioned earlier on the wrong side of the insulating washer, that will gound you out and that will be your problem.

You just asked, when are the points supposed to be closed? When they close isn't very critical. It's important when they open or Break. When the "F" mark on the flywheel just starts to line up with the mark on the case, (should be just above the flywheel on the centerline of the crankshaft) the points should break at that point. One thing to look for when checking those points. If they are adjusted so wide that they never close, the ignition won't fire. They only fire when they break. If they can't make, they can't break. Take another look confirm what is working and come back and tell us what you find. I'm sure your stareing the problem right in the face.
 
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