Hello - I have a Dinili 90cc Diamond Back -
I am having trouble with the electrical igniition - I have done a lot of test from this forum = thank you Lynn==

I believe I have a bad ignition coil - for when cranking the engine - the spark is off and on - I've verified this by holding the spark plug onto the frame/chasis and visually saw that I was getting spark for 2-3 seconds then nothing .. then again .. for 2-3 then off -- then nothing from there on.

Is my diagnosis correct? Please advise.


Thanks.

 

Maybe it is a bad ignition coil, but it could be other things as well. The best approach is to measure all the things you can with a meter (such as kill switch wiring, the stator output, wiring, coil winding continuity, and parts of the CDI) then change things that you can't completely measure (such as a bad spark plug or high voltage breakdown inside the coil).

The first thing I would do is disconnect the kill switch wire at the CDI and then check for continous spark (more than 2 to 3 seconds). Next measure the AC power voltage with the CDI disconnected. Should be around 50 - 80 volts AC cranking. Be sure to measure it for more than 2-3 seconds to make sure you are getting past the initial period where you are getting spark. Then measure the ignition tirgger pulse AC voltage. This will be a really low voltage like 0.3 volts AC while cranking so be sure to set your meter on the lowest AC voltage scale.

I see you've been reading lots of other posts so I didn't reproduce the same pictures and test procedures over again. If you have any questions or need more detailed explanations just ask. Also note that the 5 pin CDI and the 2 connector (four pin and 2 pin) AC powered CDI are exactly the same inside other than the connectors. So techniques for one apply to the other and vice versa.

 

Lynn thanks for the reply.

Well I've measure the CDI unit .. with surprise - Dinli website has some ignition test procedure .. I perform those and believe my CDI is function .. ]
I'm getting 78 V on the Orange wire ( going to the coil) and
38 V on the black wire - I believe going ground..

I've getting about a 35 V at the coil - before the magnification..

thus since my spark is interment or simply weak .. I think its the coil..
I'm going to order one and see if that solves it ..
I will post result .. to let you know and .. anyone else running into a similar situation..

thanks..

 

You're a better man than me, because I looked and couldn't find a Dinli ignition test procedure. Could you post a link?

The test results you posted are very suspect. You're getting 78 volts on a wire going to the coil, and 38 volts on ground. Ground should be zero volts, or it isn't ground. There's only one wire going to the coil from the CDI. You got 78 volts at first, then in another sentence you said you got 35 volts. All of this makes no sense to me. Especially since you need an oscilloscope to measure the ignition coil primary voltage accurately. You can't use a voltmeter.

I'd like to see the Dinli procedure to see if I can make any sense out of it. Then lets go from there...

 

The procedure states to disconnect the orange and black wire -

orange going straight to the ignition coil ..
black getting grounded - I don't know why .. but that we it is..

the procedure ask to test voltage on orange and black..
after it states to ground the black and test orange (should be getting somewhere from 30-45 V)

I absolutely agree... if black has any voltage why the heck is it going to ground...
THIS is exactly why I need a second opinion..

 

Normally when testing the ignition system one of the first things you do is measure the ignition power voltage on the stator. You do this by disconnecting the CDI (or wires going to the CDI) and measure the *AC* voltage at this point. 30-45 (*AC*) volts sounds low to me for ignition power, but it might work. My quad measures 80 volts AC cranking. Others have reported down to 35 volts AC with the quad running.

I'm wondering if the voltage you are trying to measure is the AC ignition power and not the ignition coil voltage? Does this procedure say you should measure AC voltage or DC voltage?

I am very suspicious of any procedure that says you can measure the voltage on the ignition coil primary with a meter. Meters aren't designed for this. You need an oscilloscope. And you certainly wouldn't measure a steady 30-45 volts AC *or* DC. It makes no sense to me.

I believe you when you say you have a procedure. Since you didn't provide a link I'm thinking you can't post it for unknown (and maybe good) reasons. Perhaps it is proprietery, or in a non-english language.

So can we make our own procedure? Let's start with measuring the AC ignition power voltage coming out of the stator (CDI disconnected) while cranking the quad. What is it? Do you know how to do this? I can provide more detail if necessay.

When you talk about orange or black wires it means nothing to me. Wire colors vary from machine to machine. Do you have wiring diagram? If not then we will have to go by where wires are connected and not on what color they are.

 

Lynn

Thanks for responding thus far ...

I like to inform everyone that my new ignition coil did the job..
For safe haven, I've also replace the fuel filter and did a carb job.

All is working and running now..
Now the issue is setting/calibrating the carb ...
DOES ANYONE have some set of direction - step by step and something so simple that a monkey could do it

FYI - its a 2 stroke - 90cc - single carb / oil injected.


Thanks everyone.

 

I'm glad you got your quad running .

I'm not much help on 2 cycle engines. The last time I had anything powered by a two cycle engine was on a go cart powered by a Muccullough chain saw engine in 1974.