We cut the black and white wire that goes to the kill switch and still no fire to the spark plug but we tested the plug on another 4wheeler and had a spark .

 

We think we have a 150cc but not sure and it is a 4stroke .

 

That eliminates the kill switch input to the CDI.

The 2 plug 6 wire CDIs come in two different designs. One is powered off 12 volts DC, and the other is powered off a moderately high voltage AC which comes from the stator. Unfortunately there is no reliable way to tell the difference between the two by just looking at them. To be sure you need to use a meter to find out which you have:

A) Unplug the CDI, and turn on the ignition. Do not crank the starter motor. Use a meter to measure the *DC* voltage on the pin labeled "AC ignition power" in the wiring harness to the ground pin in the same connector. If you measure 12 volts DC then you have a DC powered CDI. If you find that you have DC powered CDI then let us know and we will need to back track a bit.

But I'm going to assume you have the more common AC powered CDI since most (but not all) DC CDIs don't have a kill switch wire at the CDI connector.

1) Unplug the CDI. Turn the ignition switch on. Set all kill switches the the "run" position.
2) Use a meter to measure the resistance of the AC ignition power pin in the wiring harness to the ground wire. You should read approximately 400 ohms. What do you measure?
3) In a similar fashion measure the resistance of the Ignition Trigger Pulse pin to the ground pin. You should see 150 ohms or so. What do you measure?
4) Switch your meter over to measure AC volts on the 200 volt scale. Leave the CDI unplugged. While cranking the engine, measure the voltage on the AC Ignition Power pin in the wiring harness to the ground pin. You should measure 40 to 80 volts AC. What do you measure?
5) Set your meter down to the lowest scale you have for measuring AC volts. 2 volts would be ideal, but some meters don't go that low. In that case use the lowest scale you have. While cranking the engine, measure the voltage on the Ignition Trigger Pulse pin in the wiring harness to the ground pin. You should measure 0.2 to 0.5 volts AC. What do you measure?

The CDI is in the middle of the ignition system. The tests above are measuring the inputs to the CDI to see if they are up to par. If they aren't it points back towards the stator (because you have already eliminated kill switch issues [the other CDI input] by cutting the black white wire). If they are up to par then we look further at the CDI itself or ignition coil.

 

We have no voltage that is goin to the cdi box on any
Pins

 

That would be extremely unlikely. It would require multiple problems all happening at the same time.

If you're trying to use a test light then you are wasting your time. Get a meter. They are cheap - a lot cheaper than all those parts you've thrown at this problem so far . A meter will do everything a test light will do and much, much more.

Besides voltage, the procedure above asked about resistances. Diagnosing problems is easier when you have complete data sets to work with .

When reporting measured values be sure to list exactly what you measured - like 272.4 ohms or 32.6 volts AC. If you measure and open circuit then say it is open, etc. Note that vague statements such as "I got nothing" or "It all measured good" are not helpful at all.

 

The black and white wire that you cut, Was it at the brake lever? If so then the 2 wires have to be connected to each other in order for it to fire.

I don't know if this will help, But LynnEdwards is a wizard at all that spark stuff. If you can describe it in good words and what you have did he can tell you how to get fire to the plug.
It seems you have done a lot of things to the bike without results. Maybe you need to slow down and do a step by step on the bike. Lynn will help you, and like I said he is good.

 

I told you something wrong, incorrect. The 2 wires, that you cut will cause the starter switch NOT to work, IF they were at the brake lever. If you bypass that safety switch the wires must be connected to each other. Same on the tether switch in back.EXCEPT the tether switch will stop spark to the plug. It is a kill switch.


In my case I was over thinking things when mine was not running. Most of the time it is simple, easy things that go wrong. Most of the time, with the wiring, check and re check what you have done. Wires will pull loose when putting it back together.

 

This 4-wheeler was running then one day it just would not start. We tried a new magneto , then it would still turn over , but still won't start . So we decided to try a new cdi that did not change anything it just turns over. Well we try a new coil still just turns over but no fire , we even try the spark plug in another 4-wheeler and we have spark. We used the ohms meter that you tol;d us about but we get .01 or nothing at all. the brake light works when we turn it over. Could it be in the wiring ?????
We just don't know anything else to do.

 

The problem with throwing parts at a non-working quad is that often the original problem is a simple problem in the wiring, then one of the new parts is also bad, and now you have two problems. Two problems isn't twice as hard to fix, it is more like 10 times harder. And if you have three problems, yikes...

There are a lot of things involved in making spark. The proper way to troubleshoot is to make measurements with a meter as outlined earlier. These measurements have to be done accurately and must be repeatable. For someone new at this it takes practice, but it is worthwhile in the end.

Your reported getting resistance measurements of "0.01 or nothing". You measured 0.01 what? Ohms, kilohms, megohms? And there is no such thing as measuring "nothing" What does that mean? Your meter display vanished? The display must have read something. Zero ohms? Infinite ohms? How am I to know? Report exactly what you observed. Feel free to use a paragraph or two if that is what is required.

Lets talk a bit about measuring resistances, but start with an analogy that most will undertsand - measuring weight with a scale. We use weight scales to measure envelopes for mailing letters (fractions of an ounce) all the way up to truck scales that weigh the weight of a fully loaded semi (tens of thousands of pounds). If you want to measure a letter you can't use a truck scale - it will still measure zero pounds even if you put one thousand letters on it. A truck scale doesn't have enough resolution to measure all the down to less than an ounce. You can't measure a fully loaded truck using a postage meter. It will read the maximum weight (assuming it survives the weight of the truck) same as if you put a 10 pound bag of potatoes on it. You have to use the appropriate scale to get meaningful results when measuring weight based on what you are trying to measure.

Your meter resistance measurement capability spans an incredible range of resistances - from fractions of an ohm all the way out to millions of ohms. To get meaningful results you must use the proper scale (range) on your meter.

To span that range of possibilities there are abbreviations used:

1 ohm = 1000 milliohms
1 Kilo ohm (1K) = 1000 ohms
1 Mega ohm (1M) = 1000 Kohms, or 1,000,000 ohms

If you are trying to measure 400 ohms (0.4K) you need to set your meter scale (range) to something slightly higher than what you are trying to measure - like 2K ohms full scale. It is like if you wanted to measure the weight of a person. You would choose a scale that had a maximum of 500 pounds (or so). You would not use a scale with a maximum weight of 50 pounds, nor would you use a scale with a maximum of 500,000 pounds (500K pounds).

Think about this again. Your meter can measure resistances that span a range of 10 million to one (or more), and give accurate results to boot. Try that with a test light! On or off - if only life were that simple. A meter is an incredibly powerful tool, but it does require some careful thought to get onto the right scale.

Those resistance measurements are important. So are the voltage measurements. They point the way. Do we look backwards at the stator, or forwards to the CDI and beyond.