Wet ride+hose down=no spark

[YOSH812]

After a wet and muddy ride-complete with hose down by my 7 year old daughter, her 110cc Roketa mini quad (Shineray) has no spark. I contacted PowersportsMax ,talked with Manny and he was pretty sure it was the CDI box. I bought a CDI, coil w/wire+cap,and key switch on E-Bay($28.50 for all). So far I've unwrapped all wiring, visually checked, some connectors were wet -took apart handlebar kill switch- seems to work,all wires are intact.I also unplugged the tether kill switch-still no spark. When I crank the engine with the headlight on ,it does start to glow.(stator ok?).The only other module in the system is the rectifier.Is there any way to test it, the CDI, and the stator? The main fuse has not blown so I'm ruling out a wiring short. It's just my luck that my son's ATV(70cc Tomoto made by Jailing)has a different ignition system so I can't swap parts to test them. Any ideas will be appreciated. (I'm ready to pull out the hair that hasn't allready fallen out !) Thanks

[phil]

something in here may match yours http://www.chinariders.net/modules.p...ghlight=#62429

[LynnEdwards]

Does your CDI look like this?


If not can you post a pic of your CDI?

If so, then measure from the kill switch pin to engine ground with an ohmmeter. It must be open (infinite resistance). If this line is shorted to ground you will not get spark. This eliminates all the kill switches and associated wiring. My quad has three kill switches- the tether, left handlebar, and one pole of the ignition switch. It is very common for the kill switch wire to the rear tether to short to ground under the seat.

Does your quad have a remote start system? Unplug it and try again.

Witht the CDI disconnected measure the voltage on the AC Ignition Power pin in the wiring harness to engine ground while cranking. You should measure 80 volts AC or so. Be sure your meter is set to measure AC volts. This measures the power supply for the CDI which comes from the stator.

Measure the voltage on the Timing Trigger pin the same way. While cranking you should see a small AC voltage of around 0.2 to 0.5 volts AC. It is actually a complicated waveform consisting of short +/- pulses with long periods of nothing in between. Voltmeters don't do a good job of measurring waveforms like this, but you should measure something. This voltage also comes from the stator and is used to tell the CDI when to fire the plug.

Forget aboout the rectifier/regulator. It has nothing to do with spark.

Make sure your ground wire to the CDI is really grounded. Measure your Ignition coil pin to engine ground. You should see just a few ohms. This measures the wiring through the ignition coil primary.

[YOSH812]

Yes,the CDI is a 5 pin, and the atv does not have remote start. I need to buy a multi-meter and follow the very detailed test procedure.Thanks LynnEdwards,I'll post after the test.(might be a few days)

[katoranger]

Walmart sells a little digital meter for about $20. Great addition to the tool box. I luckd out on a Fluke on garage sale for a $1.


Allen

[YOSH812]

Here are the test results: battery OK@ 13.5 volts. Stator volts- 42 volts ac max. Other tests do not show a short. I did not test the firing pin on stator. Now the questions. Are all stator outputs the same (or close to 80 vac)? There are 2 wires going to the rectifier/regulator,coming from the stator plug in. Is it possible the regulator is the demon? There is some corrosion on the base of the regulator pins. I'm looking to spend as little as possible - regulators are cheap- stators are not so cheap.Is there a way to test the regulator? Once again thanks , We seem to be narrowing this problem down.

[forchetto]

The regulator has nothing to do with the ignition. This is self powered direct from the magneto. The AC voltage from the magneto's exciter winding varies with the speed and 80 is about right at fast cranking speeds. It's a high impedance source, so any meter that draws too much current to effect the measurement will load it down. I've made a tester that visually confirms that the output from the exciter coil is OK:



Does it have one of those metal-clap spark plug caps?. Best to remove the cladding if you have, or fit a new all plastic cap. Those caps have been a pain in the ass since time immemorial. Water gets between the cladding and the cap and it shorts the ignition out.

[LynnEdwards]

As Forchetto said, the regulator has nothing to do with ignition. It has to do with keeping the battery charged and nothing else.

Batteries on non-running quads measure 12.6 volts (or lower if it's partially discharged). So how did you get 13.5 volts? I would measure that again. Maybe you had a charger hooked up at the time?

Regulators are easy to test. You start up the quad, rev it a little, and measure the battery voltage. The charging system (which includes the regulator) should raise the battery voltage from 12.6 volts to somewhere between 13.5 and 14.5 volts DC. So forget about testing the regulator until the quad is running.

42 VAC for the ignition power winding sounds low to me, but I can't imagine a fault in the stator that would cause the output to read a little low. Usually it is OK or measures really really wrong. I think you would still get a spark with 42 volts AC. The output voltage of the stator varies with cranking speed (as Forchetto said).

Next I would measure the voltage on the kill switch pin of the CDI while hooked up and while cranking. This is a complicated waveform, so take both DC voltage and AC voltage measurements and report back.

You really do need to measure the trigger winding voltage. Just because it puts out a small voltage doesn't mean it isn't as important.

[LynnEdwards]

Forchetto,

Your GDT ignition voltage tester is very clever. A while back I tried making one using a neon bulb from a local electronics store (as a field test device) but it glows too dimly to see in sunlight.

I have a box of various GDTs at work but they all have ceramic (opaque) housings. I'll see if a can find a source for a transparent one.

[YOSH812]

Test #2 - battery 12.53v (off charger) - kill switch pin on CDI plug-in .01 ohms (same reading w/ handlebar kill switch on or off) - ignition power pin 47.1vac - timing trigger .2 no reading .2 no reading .2 etc...while engine is cranking. ignition coil to ground 2.8ohms - I disconnected the tether kill switch and hooked wires to tester-47volts, I'm removing the tether , and connecting the wires together. handlebar multi-function switch looks good inside ,but starter button does not work without moving the kill switch a few times. (it does this once in a while). Starter does not work with kill switch OFF ,but does work with tether wires connected or not.(w/kill switch on). Brake lever safety switch works OK. Ground wires are soldered together in the middle of the harness,then one goes to engine case bolt. I have a new coil with NGK cap and new NGK plug. I admit that I am so confused :? My guess today is the handlebar switch

[LynnEdwards]

Originally Posted by YOSH812

...kill switch pin on CDI plug-in .01 ohms (same reading w/ handlebar kill switch on or off)...

No, that is completely wrong. 0.01 ohms to ground is the same as a short to ground. That "kills" spark, and keeps the engine from starting.

Originally Posted by YOSH812

...I disconnected the tether kill switch and hooked wires to tester-47volts...

This is conflicting information. The tether switch is wired to the kill switch pin on the CDI on one side and to ground on the other. If you really have 47 volts on this wire (the kill switch wire) then it can't possibly be shorted to ground, and you can't possibly have 47 volts.

Unless, that is, the kill switch is shorted to ground *until* you disconnect the tether switch. If that is the case you've found a major problem (I suspect you have more than one).

When the tether strap is plugged in the tether switch is forced open, disconnecting the kill wire from being shorted to ground and allowing the CDI to produce spark.

Originally Posted by YOSH812

...I'm removing the tether , and connecting the wires together...

No. You have it backwards. You leave the tether switch wires disconnected to disable the tether switch. Shorting those wires together disables the CDI from generating spark. Your quad will never start as long as those wires are connected together.

Originally Posted by YOSH812

...handlebar multi-function switch looks good inside ,but starter button does not work without moving the kill switch a few times. (it does this once in a while). Starter does not work with kill switch OFF ,but does work with tether wires connected or not.(w/kill switch on)...

I'm confused on this one. The kill circuitry has nothing to do with the start circuitry. The purpose of the kill switch is to stop a running engine. You can't stop the engine with the starter motor, so this makes no sense. Inside the handle bar switch (on my quad at least) is a kill switch, headlight switches (low and high beam), and the start button. They are all separate from each other and don't interact.

If you can't get the CDI kill pin to *not* be shorted to ground, then I would pull out the kill pin from the wiring harness and see if you get spark then. Be aware that if the quad does start you won't be able to turn it off with the ignition switch or the kill switches. Make sure you can stop the engine some other way such as pulling the ignition trigger wire (its always a safe low voltage). The voltages on the kill switch and CDI ignition power wire have *much* higher voltage on them at idle speed compared to cranking speeds and can be dangerous.