intermittent no spark (long story)

[northerngn]

I was out of a drive today,made a full speed pull and shut down to pull plugs and check how they look.
They looked great, I reintsalled them and pulled to start the motor and the rope broke.
I walked home(i was close) and then walked back to sled pulled recoil installed new rope and re installed the assembly.
Still wouldn't start.
Checked and found no spark and towed it home
After playing with some wires at he coil i magically had spark and drove it around and it ran strong as hell(skis up) and then died
I presumed it to be a faulty coil so i put a new coil on it.
No spark
My CDI has 2 black wires pulled one at a time and both times no spark
Ohm checked the orange wire from coil location to cdi box and it was ok
Black wire good too...
Maybe i broke something in the flywheel starter area with the on and off
I know lighting is a different circuit but fir what its worth the headlight does illuminate as I pull start it
Should I pull recoil and then flywheel and check in there ?
Did I maybe wreck something?
I'm all out of ideas
HELP
-Dan

[northerngn]

Ok after reviewing the elec diagram i see the black wire i need to try to disconnect its black on the coil side and black and yellow on the cdi unit side
Tried that and well never mind there is now black and yellow
It has a black and white, black, and black
The two black wires are trermnated differently so I cant mix them up...
hmmm

[Vmax540]

Black with a Yellow stripe should be the hand warmer circuit. I suspect a bad connection in the bundle of connections that are coming out of the stator and are in right in front of the recoil. Take these apart clean and tight are the key.

viewtopic.php?f=2&t=1529

-No Spark
Two different circuits. One for lights, and one to the CDI for spark. Check the CDI for a single black wire. Disconnect this and see if you have spark. If so, the problem is in your kill switches, ignition switches, connections or wiring harness somewhere. If still no spark, check your CDI, Coils, or magneto. Becareful when checking for spark by disconnecting the black wire, as there will be no way to kill the engine if it happens to start.

[northerngn]

Cleaned connections...no change
For what its worth it did feel like it wanted to cut out a few times when it was running...

[Vmax540]

viewtopic.php?f=2&t=1529

Electrical- Mfr./ Type Hatachi/ CDI
Headlight/ Taillight/ Meter light Ratings 12v 60-55w/ 12v 23-8w/ 12v 3.4w
Lighting Coil Color Code/ Resistance/ Output Yellow~ Black/ 0.25 Ohms +/-10%/ NA
Handlebar Heater Coil Color Code/ Resistance Yellow-Black~ Blk/ 0.77 Ohm +/-10%
Ignition Coil Resistance Primary/ Secondary 0.12 Ohm � 10%/ 4.0 K ohm +/-20%
Source Coil Color Code/ Resistance

Brn~Red/ 245 Ohm +/-10%
White- Red~ Red/ 10 Ohm +/-10%
Pulsar Coil Color Code/ Resistance White- Green~ Black/ 100 Ohm +/-10%
Spark Plug Type/ Gap/ Torque NGK BR 9EV/ 0.7~0.8mm/ 2.75 m/Kg (19.9 ft/lbs)
Ignition Timing 1.6mm BTDC


B.T.W. I have had two CDI's that were intermittent....

[northerngn]

Did some ohm measuring today
As follows...
Brown to red spec 245 I had 225
White/red to red spec 10 I had 45.9 which close to spec of 50 for and 87?
White/green to black spec 100 I had 88.2
Note that it was 36 deg in the shop at the time of measuring...

-Dan

[tyler440]

i would say your coils are all good. the values are lower than what the book calls for because it was colder than the recommended (i think) 60*F.

You said you cleaned the connections but did you tighten them at all? i like to take a pair of pliers and squeeze the female ends of those bullet connectors just a hair so that the male snaps in. I know this sounds crazy but this is exactly what fixed a sled that a guy brought to us from a couple of hours away.

He thought his cdi was blown so he loaded the whole sled up and made the trip to the "vintage vmax garage" when i was switching out the cdi with a known good one i tightened the female ends a bit. the new cdi fired right up... so we put the old cdi back on and it never missed a beat either...

[tyler440]

i dont believe you tested any of the kill switches, that would be the next thing to check. check key, kill, and tether if you have one....

unplug the respective plug and put your multimeter on the switch part. it should be normally open. meaning when the key is on there is now continuity, when the kill button is up there is no continuity, and when the tether is plugged in there is no continuity.

now with these switches in "kill mode" there should be continuity.

now check the plugs where they go into the harness... one side should have ground, the other should not... if both sides have ground without and switches hooked up, you have a short to ground somewhere...

[northerngn]

Ok! I'll try that later tonight
I hope that fixes it cause a cdi box cost almost as much as the sled!
If that still doesn't fix it I was thinking of unwrapping as much of the harness as I can to eyeball all the wires...
BTW could the harness to the headlamp effect this at all or should I just concentrate on the coil and cdi back
This thing is kinda a wiring basketcase
Handwarmer wires cut, no wires off of carbs and wires near steering and coil just plugging into each other
I'm sure its all tors related bypassing stuff but maybe those having a poor connection can cause that too right?
-Dan

[northerngn]

No tether and no key
Getting key and switch off of ebay
As purchased all on and off functions controlled only by start stop switch on right handlebar

Also does it matter which side of coil the ground(black wire) is run to?
The pigtail goes to an orange wire and ground gets connected to black via eyelet

[tyler440]

you can call me, but im afraid you are going to have to start looking for broken wires or ones with rubs. i pm'ed you my number

[opsled]

Dan, What year is the sled? If it is 85 or newer it could be a TORS issue also.

The key, kill and tether switches almost never go bad and can be checked by simply unpluging them one by one and retesting for spark. If spark comes back after unplugging a switch you found the problem. On 85 and up sleds the TORS can be bypassed by unplugging the carbs from the harness and the plugging the harness wires into each other. The TORS switches in the carbs are notorious for giving problems. In many cases because of improper adjustment.

If you want to test the harness unplug the black/white stripe wire at the CDI. That is the kill wire and when unplugged it takes the whole switch/harness system out of the picture.

Testing for CDI is by process of elimination. If all the other components test out good replace the CDI.

If needed I have all the ignition components and switches, harneses, etc for all the years 83-91 that are known good. Rare to see a bad harness unless mice got to it or it's been hacked by a human.

The black wire eyelet can go either side and it should work.

262-716-3368

Good Luck,

Phil (opsled)

[northerngn]

1987
Starting at the 2 wire connector for ign switch I ohm checked the black wire with white stripe to all other locations,stop switch, module near coil, and at cdi box
All check ok .2 to .4 ohms
If I check the wire to ground and have the kill switch plugged in it has readings both open and closed switch...
I guess being that it always has a reading to ground it must be rubbed thru somewhere...
I'm guessing the harness section that is squashed under the rad hose.ugh...

Also with everything plugged in and the black wire with white stripe disconnected at cdi still no spark...

-Dan

[Vmax540]

Wiring Diagram

[northerngn]

Got that one thanks! Been staring at it for days!