2005 Yamoto 250cc Utility quad--no spark
Sep 15, 2011 | 11:21 PM
#11
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Yeah, this is true it seems when I talk to these people over the phone from time-to-time. But I lied here.........I was going to buy from them, but ended up buying the CDI on eBay...........ended up being cheaper when shipping was included. I forgot about it until logging into my eBay account today and seeing the feedback reminder pop up on me for the CDI purchase. Nonetheless though as the eBay listings I found didn't mention AC or DC. I'll update you once I get that new switch in the mail..........did get the 50cc one going today though, so some progress.
Sep 15, 2011 | 11:36 PM
#12
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[quote=raenglehart;3063256...So if I understand you correctly, the "kill switch" wire should not have 12 vdc on it at the CDI? Then how does it function? I always thought the kill switch functioned by removing the 12 vdc from the system.....or perhaps it should be wired to remove ground from the system? That could be my problem....Maybe I still don't have the left switch assy quite wired correctly. What do you think? [/quote]
You should *not* ever have 12 volts on the kill switch wire. The way this connection works is as follows:
1) When the kill switch pin of the CDI is grounded (through any one of many possible kill switches), there is no spark.
2) When the kill switch pin of the CDI is open (not connecting to anything) you have spark.
I'm looking at a schematic of a 6 pin CDI that I took apart and traced out. It may or may not be similar in design to yours, but for the one I'm looking at you won't get spark with 12 volts tied to the kill switch pin (or if you do it will be really, really weak). Having the kill switch input pin to the CDI at 12 volts is not right.
So try disconnecting the kill switch wire to the CDI, and then check for spark. Just keep in mind that if your quad starts up with the kill pin disconnected at the CDI you won't be able to shut if off. Also keep in mind that the kill switch pin on a running quad has really high voltage on it (a couple hundred volts peak
). It is current limited - after all you short it to ground to kill the spark - but the limited current available there is still enough to knock you on your butt.
So to kill a quad with no connection to the kill switch pin at the CDI, take a short wire length and firmly ground one end of it. Take a pair of insulated pliers and use it to shove the other wire end into the CDI kill switch pin. Keep you fingers out of the circuit.
This doesn't sound right either. Kill switches (on generic chinese quads) prevent spark, but do not prevent cranking the engine. The brake switch interlock keeps the starter from turning unless the brakes are applied, but this has nothing to do with spark - other than the fact that you won't get spark if the engine isn't turning...
You should *not* ever have 12 volts on the kill switch wire. The way this connection works is as follows:
1) When the kill switch pin of the CDI is grounded (through any one of many possible kill switches), there is no spark.
2) When the kill switch pin of the CDI is open (not connecting to anything) you have spark.
I'm looking at a schematic of a 6 pin CDI that I took apart and traced out. It may or may not be similar in design to yours, but for the one I'm looking at you won't get spark with 12 volts tied to the kill switch pin (or if you do it will be really, really weak). Having the kill switch input pin to the CDI at 12 volts is not right.
So try disconnecting the kill switch wire to the CDI, and then check for spark. Just keep in mind that if your quad starts up with the kill pin disconnected at the CDI you won't be able to shut if off. Also keep in mind that the kill switch pin on a running quad has really high voltage on it (a couple hundred volts peak
). It is current limited - after all you short it to ground to kill the spark - but the limited current available there is still enough to knock you on your butt. So to kill a quad with no connection to the kill switch pin at the CDI, take a short wire length and firmly ground one end of it. Take a pair of insulated pliers and use it to shove the other wire end into the CDI kill switch pin. Keep you fingers out of the circuit.
... When I push in the starter switch, I am getting the 90 VAC as I should be. With the Kill switch off, I get engine turn over when pressing the starter switch........with kill switch engaged, I push the starter switch and get nothing.....the more I edit my posting here, I am thinking I may have wired my plug wrong after all............something to do with the start and kill switch setup I assume.
Sep 15, 2011 | 11:55 PM
#13
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Yeah, you confirm my suspicions for certain along with trying my other quads/3-wheeler/motorcycles today with the kill switch on/off. I've def got the kill switch function wired wrong in the plug....I don't know why I thought it was a power circuit........makes much more since for it to be a ground circuit.......I'll give it another go tomorrow and see if I can get it right............if you are correct, that 12 vdc going to the CDI is more than likely killing my spark. My inline spark testers aren't flickering at all.............if I have as much go my way as I did today (was a good day on the projects--yes, I have several going at once), the Yamoto will be running tomorrow.....if that happens, I will be out of projects........oh my...........whatever will I do?? I'll post and let ya know how it goes tomorrow. Don't think the wife will take too kindly to me running to the workshop at this hour and not coming back in until the Yamoto is whole again....
Thanks for the info.
Thanks for the info.
Sep 27, 2011 | 11:56 AM
#14
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Need correct CDI
Well Lynn, the supposed right switch I ordered isn't right after all. But with the thread started by 01sreda4 who seems to have the same or similar quad I do, I did some re-checking which leads me back to the CDI. My old CDI had CM250 stamped right on it, so this tells me that I need to order a CDI from a Honda Rebel 250 which has dual ignition coil output firing wires. Looking at the diagram he uploaded confirms this when I ohmed out my wires from the CDI to each ignition coil. So, I am going to search for and order the correct CDI and update the thread as soon as I install it and see what happens.
I still would really like to find the correct left handlebar switch assy though..........that is really bugging the crap out of me. The middle pic is the type of plug/pin setup I need to find for the replacement switch (don't pay no attention to the wires in it though. it should be 7 wires total). This is the one from a kawasaki bayou since it was the only one I could find with the correct connector, but it only has 6 wires. And to answer your earlier question regarding why I was getting 12vdc on the Kill switch circuit, I opened the switch assy and that is how it is wired internally. Strange as I've never seen one wired like that.......the same yellow w/red stripe wire is connected to both the kill switch and start button switch?
I still would really like to find the correct left handlebar switch assy though..........that is really bugging the crap out of me. The middle pic is the type of plug/pin setup I need to find for the replacement switch (don't pay no attention to the wires in it though. it should be 7 wires total). This is the one from a kawasaki bayou since it was the only one I could find with the correct connector, but it only has 6 wires. And to answer your earlier question regarding why I was getting 12vdc on the Kill switch circuit, I opened the switch assy and that is how it is wired internally. Strange as I've never seen one wired like that.......the same yellow w/red stripe wire is connected to both the kill switch and start button switch?
Sep 29, 2011 | 08:09 PM
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Good news Lynn. After talking with the other guy with the same quad (on his thread), it was confirmed the CDI I originally got was not correct since it only had 1 cylinder firing instead of 2 like he and I have. So, I did some searching for a CM250 CDI (dual firing cylinder type) and received it in the mail today. Plugged it in and the quad fired right up...using my spark tester, I was able to verify both cylinders have spark....now to get it all put back together and give her a run around the property. I guess we all learned something a little new on these Chinese things huh? Twin cylinder's require a certain CDI (in this case, from a Honda Rebel 250 street bike). Both my old one and the new one have stamped on the outside CM250 (old one) or CM125 (new one). The CM125 is what I got today, so from what I can find online, they are interchangeable.
Thanks again for your help Lynn.
I still need to figure out the kill switch wiring on this switch I'm using, but for right now, it starts, runs, all lights work (just not the kill switch right now). So I will probably leave it alone and just enjoy some riding for a while..........the key switch kills the engine just fine.
Thanks again for your help Lynn.
I still need to figure out the kill switch wiring on this switch I'm using, but for right now, it starts, runs, all lights work (just not the kill switch right now). So I will probably leave it alone and just enjoy some riding for a while..........the key switch kills the engine just fine.
Sep 30, 2011 | 12:20 AM
#16
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Good news Lynn. After talking with the other guy with the same quad (on his thread), it was confirmed the CDI I originally got was not correct since it only had 1 cylinder firing instead of 2 like he and I have. So, I did some searching for a CM250 CDI (dual firing cylinder type) and received it in the mail today. Plugged it in and the quad fired right up...using my spark tester, I was able to verify both cylinders have spark....now to get it all put back together and give her a run around the property. I guess we all learned something a little new on these Chinese things huh? Twin cylinder's require a certain CDI (in this case, from a Honda Rebel 250 street bike). Both my old one and the new one have stamped on the outside CM250 (old one) or CM125 (new one). The CM125 is what I got today, so from what I can find online, they are interchangeable.
Thanks again for your help Lynn.
I still need to figure out the kill switch wiring on this switch I'm using, but for right now, it starts, runs, all lights work (just not the kill switch right now). So I will probably leave it alone and just enjoy some riding for a while..........the key switch kills the engine just fine.
Thanks again for your help Lynn.
I still need to figure out the kill switch wiring on this switch I'm using, but for right now, it starts, runs, all lights work (just not the kill switch right now). So I will probably leave it alone and just enjoy some riding for a while..........the key switch kills the engine just fine.
I'm at a real disadvantage never having seen one of these quads. You did good in getting this far.I need to go back and re-read both the threads and see if I missed anything about the left handlebar wiring. It's been a rough week for me. Things will wind down (I hope) by this weekend.
Sep 30, 2011 | 09:55 PM
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So I'm happy to just have it back going again. But that dang switch is going to annoy me (I'm a bit of a perfectionist). And to add to my confusion, the other guy said his switch assy had a female pinned plug. Mine is a male pinned plug, so even our supposed same model quads aren't exactly the same I reckon.
Anyhow, thanks again for all your help...........
Jul 23, 2025 | 09:50 PM
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Yamato atv 250
This is a twin cylinder/twin carb type. I have no spark at either of the two plugs. I replaced the CDI (I shorted it out on accident--crossed some wires). Here are the checks I've done so far based on other threads I've read:
I have the pictured CDI type below and all readings are done at it's connectors
Attachment 16916
Wire colors are as follows:
2-pin plug
A/C Ign Power: Black w/red stripe
Kill Switch: White w/black stripe
4-pin plug
Ignition trigger Pulse: Blue w/yellow stripe
To Ignition Coil:Black w/yellow stripe
Ground wires (2 of them): one black w/blue stripe and one green
Here are instructions I pulled from another thread regarding no spark on a different type of quad and my test results.
Set your meter to read AC volts on the 200 volt scale. Test your meter by sticking the probes into a wall power outlet in your house. You should see about 120 volts AC. If you get that you know your meter is set up properly and working.
Now disconnect the CDI from the quad wiring harness. Measure the AC voltage on the AC ignition power pin of the wiring harness to engine ground while cranking the starter motor. That will be putting one lead on the wiring harness pin, and the other lead on the aluminum motor block. You should see 45 to 80 volts AC at normal cranking speeds. What do you measure?
A: 95.2 VAC
Set your meter to the lowest AC voltage scale that is has. 2 volts AC full scale would be ideal but many meters don't go that low. Use whatever the lowest range is, but make sure it is AC volts and not DC volts. Measure the voltage on the timing trigger pin in the wiring harness to engine ground while cranking the starter. You should see 0.2 to 0.5 volts AC. What do you measure?
Now, I assume this is the ignition trigger pulse, but again, this troubleshooting guide was for a different type CDI (single plug 6 pin)
A: Lowest setting is 200 VAC. Reading was 00.0 VAC
Set your meter to measure resistance (ohms) on the 2K ohms scale (2000 ohms). When on the resistance settings you should read zero ohms with the leads shorted, and infinite ohms when the leads are not connected together.
Turn off the quad ignition switch. Measure the AC Ignition Power pin on the wiring to engine ground with the engine sitting still (not cranking). You should see 450 ohms or so (0.450 Kohms). Measure the Timing Trigger line to ground. You should read 150 ohms or so (0.150 Kohms) with the engine sitting still. What do you measure for both of those pins?
A: 320 ohms / 149 ohms
Set your meter to the lowest resistance scale it has (20 ohms is about right).. Measure the resistance of the ground pin in the CDI to engine ground. It should read zero ohms. Measure the Ignition coil pin to engine ground. It should 0.5 ohms or so. It should not read zero ohms. Report back any discrepancies with these two values.
A: 2 each ground pins (both read 0.1 ohms) / Ign coil to ground 0.5 ohms
I am unable to find a wiring diagram for this quad anywhere online. The one I did find wasn't even close, even though it said it was for a Yamoto 250cc. Any guidance as to where I go next?
Thanks,
Roger
I have the pictured CDI type below and all readings are done at it's connectors
Attachment 16916
Wire colors are as follows:
2-pin plug
A/C Ign Power: Black w/red stripe
Kill Switch: White w/black stripe
4-pin plug
Ignition trigger Pulse: Blue w/yellow stripe
To Ignition Coil:Black w/yellow stripe
Ground wires (2 of them): one black w/blue stripe and one green
Here are instructions I pulled from another thread regarding no spark on a different type of quad and my test results.
Set your meter to read AC volts on the 200 volt scale. Test your meter by sticking the probes into a wall power outlet in your house. You should see about 120 volts AC. If you get that you know your meter is set up properly and working.
Now disconnect the CDI from the quad wiring harness. Measure the AC voltage on the AC ignition power pin of the wiring harness to engine ground while cranking the starter motor. That will be putting one lead on the wiring harness pin, and the other lead on the aluminum motor block. You should see 45 to 80 volts AC at normal cranking speeds. What do you measure?
A: 95.2 VAC
Set your meter to the lowest AC voltage scale that is has. 2 volts AC full scale would be ideal but many meters don't go that low. Use whatever the lowest range is, but make sure it is AC volts and not DC volts. Measure the voltage on the timing trigger pin in the wiring harness to engine ground while cranking the starter. You should see 0.2 to 0.5 volts AC. What do you measure?
Now, I assume this is the ignition trigger pulse, but again, this troubleshooting guide was for a different type CDI (single plug 6 pin)
A: Lowest setting is 200 VAC. Reading was 00.0 VAC
Set your meter to measure resistance (ohms) on the 2K ohms scale (2000 ohms). When on the resistance settings you should read zero ohms with the leads shorted, and infinite ohms when the leads are not connected together.
Turn off the quad ignition switch. Measure the AC Ignition Power pin on the wiring to engine ground with the engine sitting still (not cranking). You should see 450 ohms or so (0.450 Kohms). Measure the Timing Trigger line to ground. You should read 150 ohms or so (0.150 Kohms) with the engine sitting still. What do you measure for both of those pins?
A: 320 ohms / 149 ohms
Set your meter to the lowest resistance scale it has (20 ohms is about right).. Measure the resistance of the ground pin in the CDI to engine ground. It should read zero ohms. Measure the Ignition coil pin to engine ground. It should 0.5 ohms or so. It should not read zero ohms. Report back any discrepancies with these two values.
A: 2 each ground pins (both read 0.1 ohms) / Ign coil to ground 0.5 ohms
I am unable to find a wiring diagram for this quad anywhere online. The one I did find wasn't even close, even though it said it was for a Yamoto 250cc. Any guidance as to where I go next?
Thanks,
Roger
anyone know the wiring? what colour goes with what colour?
cover
wire schematic
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