1992 YFS200 Blaster has me stumped

My young nephew bought an old 1992 Blaster, and it quit running soon thereafter. (spark plug not firing.) He asked me to look at it and I agreed. No fire on plug cap, it tested bad according to the Hayne's Manual. Changed cap still no fire. Ignition coil tested o.k. Pickup coil tested 20 ohms. The manual calls for 72-104 ohms. Now we're getting somewhere right? changed pickup coil and the new one also tested 20 ohms. no fire. Returned it to dealer as defective and got a replacement. Installed new coil, tested 20 ohms again Called Yamaha mechanic, he said 20 was about right, not 72-104. Still no fire. Source coil tested ok but replaced anyhow. still no fire. Carb. switch tested bad (an open with throttle open or closed.) This is the run position so I disregarded. Throttle position switch tested good. Control unit tested good. Handlebar kill switch tested bad and I replaced. Still no fire. Ignition switch is missing so I simply left those 2 grounds free. (it breaks for run position) Control unit tests good. The manual says if all tests ok to replace the CDI box. I did. Still no fire. As a last ditch effort I replaced the wiring harness. Still no fire!!! I tested the individual wires and solder connections to the coils and all showed continuity. All magnets on the rotor seem to grab a screwdriver about the same. Anyone with any ideas would be extremely helpful.

Thanks very much
Phillip

 

Does this have a battery?? Check your voltage to the ignition coil when it is being started. All of your components may be good starter dwawing voltage to coil lower than the ign circuit threshold.Post back.
STIMPY21

 

Stimpy, The machine has no battery. It is a mgneto type cdi ignition. There is no electric start. Kick start only.

Thanks, Phillip

 

Do you have a schematic that you could send to me?? If I have resourses I am rarely stumped. I am asuming that the magnets spin inside of a coil and that is what makes the primary ign voltages that feed the hv coil which makes the secondary or hv to the plug. Most usually when something like this happens some minor detail is overlooked, and that detail end up being critical. I remember working on an Austin-Marina car once and there were 2 washers, fiber one and a steel one, it went fiber first and then the steel, reverse them and the points were effectively grounded out.Of course I reversed them and took several hours to figure it out. I must ask this is there any primary voltage to the ign coil?? It sounds like something is grounding you out. Shoot me a schematic if you got them and we'll go from there.
STIMPY21

 

I have the same feeling as you, that something has the system grounded. At the stator I believe. I am a fair mechanic,but am not well versed in the theory or operation of magneto ignitions. I attempted to check output by connectingmy multi-meter to each coil's output wire. the lighting coil showed about 4.5 volts at kick speed. I figured this was ok. at least it showed some output. the source coil and the pickup coil were inconclusive. I don't think either of them were doing anything.

As for the schematic,yes there is one in my manual. I'll check up with someone more computer literate than myself and find out how to get it to you.

Phillip

 

I have purchased a scanner. I'm not sure how to get the schematic for the Blaster posted to the web, but I can send it to an E-mail address pretty easily. If you can give me an address to send it to I'll get right on it.

Thanks, Phillip

 

Phillip Check your Pm.
STIMPY21

 

The push-button kill switch on the handlebar is notorious for going bad. Disconnect the kill button wires and check it. If the kill button was the problem, you'll have spark with the button disconnected.

 

Check the safety switch on the oil tank it will ground the ignition if it thinks there is no oil in the tank.

 

Not that you are lookin here any more for help... old reply but ill throw in my 2 cents worth anyways

Check the stator coil.. you know the one under your fly wheel
i recomend clymer manuals over haynes... haynes asumes you already know everything and its their job to remind you as briefly as possible.

Anyways if stator coil bad then you get no spark, although usualy when they go bad ride will start when cold and run till warm then quit.

 

did you ever get the blaster running ??