I can't get it to spark, ideas welcome

[AndyAndyAndy]

The mess looks like this. The main point I think is, that it's not mounted on a frame. For example the body of coil won't be automatically grounded...and stuff like that.



And current wiring looks like this. (I think it is readable?)



I tried this (and variations of this, but the picture is my best guess). Which didn't give me a spark. I actually run it all as a wires. Even the ground from the end of spark plug.

 

[Karttekk]

What happens if you fasten a ground wire from the engine block to a nearby metal pipe or something similar then try it?

 

[madprofessor]

Wish I knew how to help, but the whole bit of a rectifier and such is outside my experience. Itsid commented extensively on those in another post, pretty sure he could help.
What I do know about is straight up coil, spark plug, and ground. My motors have a coil bolted to the metal casing, and a single wire hanging from it (besides the 8mm silicone plug wire). That wire is there to go to a kill switch, which simply dead-shorts the wire to the ground (casing) when you kill it.
I'm sure you can picture that situation, if the wire touches any grounded metal then all the spark will go to the ground with none left for the spark plug. So............no spark? Maybe, but not necessarily no power to make a spark. You must make sure there's no incidental grounding out in that situation. Then a simple test of shoving a screwdriver into the plug wire boot, holding it close to the casing, and seeing if it jumps a spark to the casing will clear up that mystery.
Must defer anything more complicated to others, I grew up just racing stripped down dirt bikes.

 

[madprofessor]

Should have mentioned............. "grounded" casing only means the metal that the coil is bolted to. The frame thing comes into play only when isolated from the motor by rubber motor mounts, so that if you want to ground it out to kill it, say maybe with a separate ignition swith or E-stop slapswitch, you'd need to attach a wire from the frame to the casing to make them both together a big grounding area. As far as getting the plug to spark, you only need to make sure the coil's ground wire isn't touching any metal that leads back to the coil's mounting point (in my straight up example).
BTW: Get a spark from the screwdriver as mentioned before, then put the plug into the boot and hold it metal-to-metal against the casing. No spark.......... bad or highly carboned (sooty) plug.

 

[AndyAndyAndy]

Thanks so far, will try tomorrow!

 

[AndyAndyAndy]

LOL

As I was turning kick start my wife was passing by. And she asked, if that shiny thing (magneto rotor) shouldn't turn when I'm turning kick start. As it usually do. I was so preoccupied by solving wiring, that I didn't notice that kick start isn't engaging rest of the engine. So I spend 4 hours kickstarting it why non moving rotor was right at my face. See photo. It couldn't be more obvious.

Wiring was then a piece of cake.

 

[landuse]

Oh no!!!

 

[madprofessor]

Wow! Guess you didn't have any problem with a kickback slapping you in the shin.

 

[AndyAndyAndy]

ha ha ha

One hand on kickstart. One hand holding engine. Eyes on spark plug. Whenever I could notice the fail, rotor was under my armpit/behind me. I had no idea. And kick start was stiff and noisy as usual. It just didn't engage properly.

 

[madprofessor]

See my post on thread 'Predator 212 tossed a rod", where it says if it's on a bench "BOLT IT DOWN!". You running that kickstarter by hand would be the same thing. What kind of motor is that anyway? Come out of a motorcycle?

 

[AndyAndyAndy]

See my post on thread 'Predator 212 tossed a rod", where it says if it's on a bench "BOLT IT DOWN!". You running that kickstarter by hand would be the same thing. What kind of motor is that anyway? Come out of a motorcycle?

Yes. I bought 50cc bike and this engine was in it. Bottom is 50cc, cylinder and head is 110cc. It's a work done by previous owner. After this "upgrade" he sold it, as he couldn't get it running. Parts aren't compatible in the first place. He sold it to me as a good running bike that just needs some basic tweaking.

I took that engine out and replaced it with 125cc from another bike. Bike is now running and that project it's done. But this engine ended up laying under my bench. So as a fun project I'm trying to figure out if I could make it run anyway. Not that I would have any use for it right now.

 

[madprofessor]

You enjoy fishing? I'm thinking boat anchor.

 

[AndyAndyAndy]

You enjoy fishing? I'm thinking boat anchor.

I'm currently repairing side stand on another bike. And I'm using that engine as a support under the bike while the side stand is removed.

I think I will get ton of usage out of that engine. But I don't think it will involve any higher speeds than me carrying it around workshop.

 

[mamoudad]

So, I have a 2010 Tahoe 9000 watt generator that has a Chinese420, 16 hp engine that I'm using for my build!! Problem is, once I separated the engine from the gen, I lost all fire! It is the electric start model!! Any help plz, I cant find a wiring diagram for it and I'm also willing to do away with the whole electrical system and just use the recoil! Greatly appreciated guys!!

 

[mamoudad]

So, I have a 2010 Tahoe 9000 watt generator that has a Chinese420, 16 hp engine that I'm using for my build!! Problem is, once I separated the engine from the gen, I lost all fire! It is the electric start model!! Any help plz, I cant find a wiring diagram for it and I'm also willing to do away with the whole electrical system and just use the recoil! Greatly appreciated guys!!

I solved the riddle, bad/broke plug!