Jonway YY250t - 2 years later, still not running... By johnny3d (Read 14,345 times)

[johnny3d]

I was just looking and I can order a new ignition coil and CDI for $31...($40 with shipping costs) which is about how much a new multimeter would cost me.

Thanks for your help so far, by the way... I'm just getting a bit disheartened because what should have been a simple carb adjustment is snowballing into more and more cost.

[ellpee]

FWIW, I've been having similar won't start problems with my Magnum trike because I'm running at very high altitude and therefore way too rich. Plug loads up with black crud within 15-20 miles, and within 50 it gets so bad I have no spark. When I clean the plug as well as possible with wire brush and solvent, then put it back in the boot and ground it to the frame somewhere and crank, I get good spark again and the scoot will start. Drive it a ways and the plug blacks up and I have to do it over again. Don't despair, keep working the plug angle as Suspect #1. And BTW, multimeters can be had for well under $30, shop around a bit. (As far as my own underlying problem, I'm getting the carb re-jetted for high altitude, but it doesn't sound like you're high enough to need that, tweaking the mixture should do it once you get it running again.)

[johnny3d]

I heard it might be a good idea to re-jet it since I'm at about 3500-4000 ft. I've also heard that if I switched from the airbox to a UNI pod filter than it would lean out to where I need it.

I heard from a mechanic guy I called that I can take the ignition coil down to a NAPA and they'll test it for free. So I'll run that down there tomorrow and see if that's functioning or not. If that is functioning that is one less item on the list that I would need to replace to find the culprit in my system. If the ignition coil comes up as being bad, I'll just order a new one of those. I'll eventually figure it out (with a little help from folks like you guys). ;D

[ellpee]

Don't know at what altitude too-rich troubles start kicking in. I'm at 7500', so just cranking around on the mixture screw won't cut it. I have a Roketa in Tucson at about 2500' average and it's fine.

[johnny3d]

I tested the ignition coil with a multimeter and its definitely is getting a reading with the Ohm measurement.

On the x10 setting I'm getting a .9 to 1 reading.

Next I figured I would test the wires leading to the ignition coil.

[johnny3d]

So far all attempts to track down/fix this issue have failed. I'm beginning to suspect that I need to purchase a new CDI, but I'm not certain about that yet.

[JR]

If you simply turned the carb and then put it back and now have no fire you've got a loose connection and you disturbed it when you were working on it.

First place to look is the CDI plug. With your meter set on DC volts turn the key on and see if you have 12Vdc + on the black wire. Check every wire pin on the CDI including the green ground wire. If you don't have 12Vdc on the black wire with the key on then find your fuses and check them. If you have voltage then check the black/yellow wire going from the CDI to the coil and check the green ground wire on the coil also. CDI or coils don't go bad just sitting there or when you adjust the carb. You've disturbed/created a bad wire connection, happens all the time.

JR

[ellpee]

My contribution, which may have absolutely nothing to do with your problem: I had the jets replaced on the carb of my Ice Bear Magnum because I'm running at way-above-average altitudes (7500' at my house) and in three test rides now totalling almost a hundred miles, it has made all the difference in the world. Starts, idles, and runs very nicely, wimpy on the hills but don't think that's about the carb -- more likely one or both ends of the CVT. May well be you have some other problem, just offering what I can from my recent carburetor experience.

But just a bit of unsolicited geezer advice, slow down, take a deep breath or two, don't be buying one $30 "fix" after another just to see if it works. At least a couple of times in my less-than-a-year scooter experience it has turned out to be the simple, you-can-do-it-yourself solution rather than the make-Ebay-And-Amazon-rich solution. Breathe deeply, Grasshopper!

[johnny3d]

Well... I went out and tested and found DC current on the black wire leading to the CDI. I also tested the resistance from the black/yellow wire leading to the coil and the green ground wire leading to the coil. Both tested fine. I did notice that on the coil they had the black/yellow wire connected to the 'green' lead on the coil and the green wire connected to the black lead on the coil. That's how it's been set up since I originally got the scooter but it still seems odd.

Turns over perfectly, starter seems strong. Power to the CDI and the wires leading to the ignition coil are all good. The NGK DR8EIX spark plug is brand new.

Spent about two hours fiddling with it, attempting to start it, and fiddling with it some more. Checked the carb again. Re-set all the air intake system back in place again. Adjusted the air/fuel screw to about 1.25 turns out or so. And still it doesn't want to start...

Maybe one of you guys knows a great scooter mechanic/guru in Western South Dakota who can save the day? I know you guys say I can do it myself but I've been tinkering with this problem for 8 days and am losing hope in my ability to fix the issue (even with good advice and help).

[alleyoop]

Take one of the VACUUM lines going to the INTAKE MANIFOLD and pour a teaspoon of gas down the Vacuum line Directly into the INTAKE put the hose back on and if the SPARK PLUG is firing it should fire and may start and die. If it does then turn the FUEL RATIO screw out 2 1/2 turns and give that a shot.
Alleyoop

[JR]

Question? On the older models of this scooter when the handlebar kill switch is in the engine off position the scooter will not make a sound, engine will not turn over. But on the newer models I don't know? Check the kill switch out. Turn it off and see if the engine will turn over. Then turn it back on and check for spark.

Lastly you can unpin the black/white wire on the CDI and see if it will fire. I don't believe the CDI went south with you just messing with the carb?

JR

[johnny3d]

[replyingto=admin]JR[/replyingto]With the kill switch in the "off" or "do not run" position it does nothing. Attempts to start it will not turn the starter motor on or anything else. With the kill switch in the "on" or "run/fun" position, the starter kicks on and it attempts to start the bike as normal.

I'm not sure which I would want to take off and put a teaspoon of gas into. I do know that there is gas going through the carb because I can smell it on the plug and smell/see it just inside the manifold (I think that's what it's called) when I take the carb off the head. I can also smell the gas slightly if I just let it turn over and over.

I did try the "dry" carb trick to get it to turn over... meaning that I took the metal cover off the top of the carb and put a teaspoon of gas down into the carb, put the top back on the carb and attempted to start it and got no fire.

It doesn't seem like I would have fried my CDI to me either since I hadn't even touched the CDI when I was working on the carb and what not. I hadn't disconnected any of the electrical outside of disconnecting/removing the battery. I was very careful not to short the battery or hook it back up wrong when I put it back in.

So far it seems like I am simply not getting spark. I am getting gas and air into the engine, but it simply doesn't ignite. When I've taken the plug out and held it against the block,screws, and even tried holding my finger to the tip I've gotten no spark. The ignition coil does register some resistance. The wires are definitely leading to it are definitely intact (tested with the multimeter), and the CDI's black wire is definitely getting DC power when the key is turned on.

I did notice that there is a yellow cable coming out of the automatic choke that was disconnected and a connection in the wire bundle that looked somewhat crushed. It did not look to me like that had ever been connected. So it's possible that my automatic choke has never worked properly. I did hook up that yellow wire to that connection as it was the only place a connection could hook up there, but I also don't think that is the primary issue here.

I'm going to re-tune the carb air/fuel mixture screw one more time (2.5 turns out) and try and start it again. If it doesn't fire I'm probably going to call this Outdoor Motor Sports place that sells Kymco ATV's and a number of other bikes and see what my options are about bringing it in there.

I've rebuilt carbs for 50cc scooters, taken out and installed a number of 50cc and 80cc scooter engines. Tuned a bunch of 50cc/80cc carbs... swapped jets in carbs... etc. I've worked on car engines and what not... but I'm at a complete loss as to why my scooter will not start. Essentially I'm just shooting in the dark here because EVERYTHING seems like it should just fire up or even fire up and stall or fire up and run rich or run lean or something... but it's just not firing. It just isn't getting a spark for some unknown reason.

Maybe it is a bad CDI? Maybe it's something else... I'm at a complete loss.

[richardthescooter3]

The wire off the enricher (auto choke) has nothing to do with getting spark.

[richardthescooter3]

I'd check both ends of the ignition coil and spark plug cap, they can come loose, about two years ago I had trouble starting my scoot, turned out to be a loose spark plug cap D;8

[johnny3d]

Thanks for all the help trying to solve my issue. I've tried all the things I could think of to try and it still will not start. I've put all the body panels back on the scooter and am just going to leave it dead until I can afford to take it into a shop and have some professional mechanics take a look at it. A local place says they can't promise anything since they don't sell Jonway scooters, but they said they should be able to help figure it out.

Again, thanks for the help. I'm bummed that I'm not able to ride the rest of the season, but I've tried everything you guys have suggested and everything I could think of and haven't been able to solve the issue.