Need help with fix on ignition system. Have two deserving boys that would like to ride while summer is still here. Have two units that are both 2006's but am doing one at a time. I have schematic but color codes do not map with 100 % accuracy to my quad. I am done with crankshaft generator. I pulled the flywheel and found things rusty. I removed the stator assy and cleaned it and measured the four impedances. I glass blasted the inside of flywheel and gave same a very light spray of clear lacquer. I cleaned the cdi trigger coil and reinstalled it with about 0.012 in gap. It is not, in reality adjustable apart from the slop in the mounting holes. Pulled the plug and cranking with an electric drill I measure 75 vac on black w/red to ground with an impedance to ground of 584 ohms. 12 vac on yellow w/ red to ground. 0.577 ohms to ground. 10 vac on white to ground with 0.64 ohms to ground.
And finally 0.75 vac from white w/red (external trigger signal) to ground with a corresponding resistance of 147 ohms to ground. I have not scoped the 12 and 10 volt signals but did scope the other two. The trigger is a rock solid 4 volts positive going then 4 volts neg going. Good and clean. Above voltage was measured with fluke meter with rms adjustment explaining the difference 0.75 and the 8 volts peak to peak.

I have checked and the cdi is being fed the trigger, the 75vac, black ground bus, brown B+ and also has a kill wire and the output wire feeding the primary side of the coil. Coil pri to ground is 0.27 ohms and sec to ground is around 7 k ohms. Ground lead to coil is good.

There is much more story and I have a suicide pill standing by. When I began there was a very thin spark with continued cranking and a slightly, and I mean slightly, better spark at the beginning of cranking and again at the end of cranking for a throw or two Removed plug.

I worked on these 2 years ago and replaced the cdi a that time. to no avail. I downloaded the impedance map for the cdi and have those values.

Any ideas would be greatly appreciated. Help!

Any ideas?

 

once in a while, a new NGK spark plug fixes them right up due to the anomaly of not firing under compression. i've done the checks and rechecks and cleanings before to no avail, tried a new plug and BAM, it ran. sounds like you're very thorough. no need for the pill.

 

Thanks for the reply. I am using a new plug that I have taped to the frame for spark check. I did not mention that I also jumper wired around the tether switch and the remote start stop plug with soldered connection to eliminate those as possibilities. I also bridged the key lock switch for the same reason. The B+ seems good and I have it where it's supposed to be I think. Ground bus likewise. However when I disconnect the cdi plug and look into the black ground wire back toward the battery I see a small resistance of about 1.25 ohms. That is why I pulled the tether switch and so on.

 

so you're leaving the tether kill circuit open or closed?

 

The 3 inside the modular connector are open as they always have been. The outside 2 separate wires which pass the trigger on to the cdi are now soldered and heat shrunk together.

The key lock is bypassed by two jumpers that I made up with male spade terminals.

B+ around the bike as well as the ground allows the horn, starter and front led light to work.

I wish there was an acid function test for the cdi that would go further than the impedance map.

I do have a number of resistance values that are outside of the factory map. This particular cdi is one that was purchased new 2 years ago when I was struggling then. Anyone know how far out they can be? If it is dead did I kill it? I checked the blocking diode in the start solenoid low side wire thinking that if it was passing both directions that maybe a nasty spike from that might be killing the cdi. I never actually found it in the harness but it blocks in one way and passes in the other so I declared it to be ok. No one can tell me how robust these units are but at over 85 dollars per throw I don't want to buy another only to fry it. Shops tell me that they just install a suspect into a working quad to test but I don't have one.

 

Sorry, I reread your question. The tether dead man is now physically gone from the quad and the two wires are soldered and heat shrunk.

I must confess that I bought a visually identical cdi from a supplier who declared that he has sold these particular units for use on 70 eton four strokes with no neg feedback. Well I have negative feedback for him. When I installed it the B+ fuse by the battery blew. Tried twice with same result. Not a drop in replacement for sure. It did not have the rpm limit adjustment so I'm thinking that the B+ is routed to ground inside. I'm going to drop it in a jar of acetone and chalk it up dead in my museum.

Everything I have done is pointing to a bad cdi but for the money I wanted to cover everything that might kill a new one first.

 

I was referring to the remote module bypass earlier. Both the remote and tether have been eliminated as sources of trouble.

 

it does sound like you're correct based on what i'm reading. i also suspect the CDI. are you buying straight from Eton? i can send you a genuine Eton hyperlink that has a multitude of manuals, parts lists, breakdowns, contacts, etc....hit me with a PM if you're interested and i'll send it to ya. i've used them a lot for my Etons. not that they breakdown a lot, just i work on mine and have upgraded some stuff and i love working on it. even when it don't need help, i tinker.

 

Hello I had similar problem with my eton 70 could only see spark when first hit button and when let off. Local eton dealer diagnosed for 30 dollars it was the handle bar switch cost me 75 dollars threw them. Now eton starts right up I hope this helps.

 

Thanks for the reply. It seems that the cure all for this quad is to replace the key lock or the start stop switch. Key lock is jumpered around and I have not removed the stop switch but it also is the source for the starter solenoid ground which cranks up just fine. I ordered a new cdi so we will see what happens. Thanks again.

JohnB