08 Jonway 250cc just died while riding By biggieray (Read 3,236 times)

[biggieray]

Hey everyone,

I have had a very low mileage Jonway 250cc for about 6 mos. I have had a number of small, pain in the butt issues as I've owned it.

Over the weekend, I was riding along about 60mph when the engine just cut out. It wouldn't restart. It now just seems to try to start but just doesn't seem to have the that last umph to get the motor running. It just goes raruh, raruh, raruh, raruh (sorry, but I wanted you to know what it's doing)

I talked to a mechanic who said it sounded like the CDI. I got a new one and that wasn't it.

Does anyone have any ideas on what to try next?

Thanks
Ray

[rob63]

Before replacing parts you`re going to have to narrow down the problem. It could be spark related or fuel. I take it there was no unusual mechanical noise when the engine cut out ?
Pop the spark plug out and place it in the cap then hold it against something metal on the engine, crank the starter and see if you`re getting a decent spark. If no spark then work you`re way back through the system to ignition lead/coil and so on. If you are getting a spark then take out the air filter and try a short squirt of something like 'easy start' down the intake, then crank the starter. The easy start should make it fire up for a short moment which would suggest fuel starvation to the carb.
One other thing, I think the Jonway 250 is liquid cooled, did the temp gauge go up at all before it stopped ?

[biggieray]

The gauge did not go up at all. It was within the first 10 min of starting.

I will try the spark plug next.

Thanks for the help. My dad always told me to work with my mind, not my hands so I never got a chance to learn much about engines and such. This is my first foray into this area and I really appreciate the help!

Thanks
Ray

[tvnacman]

Do you have a meter?

John

[speedracer]

If there is no spark then start thinking of replacing the coil.

[Alleyoop]

First thing is adjust your valves before messing with anything. If they are tight that will cause loss of power as well as loss of SUCTION to open the Petcock or Fuel Pump to allow gas to fill the carb.

Take the Fuel hose off the Carb put it in a container and crank it over and GAS SHOULD stream out pretty good. If it doesn't check the Fuel Filter it may be clogged. If the fuel does not stream out take the Filter Off and crank it again if it streams out then you know the Filter is Clogged. If it still does not stream out then check if its your Pump or the Vacuum line going to it.
Alleyoop

[speedracer]

I should have said before replacing the coil if there is no spark. Check the two wires which connect to the coil from the CDI. One just may have come off and there sure would be no spark.

Alley, wouldn't he have some warning signs before it just flat out and died if the valves were off such as stalling and poor starting?

[jaberwillow]

I Have a 2007 and the same thing happened to me today and it turned out that the fuel pump was bad.....luckily I have only had mine 1 month and they are sending me a new fuel pump replacement. Check it out.....mine was getting the vacuum but the pump wasn't pumping any gas up to carburetor! Unfortunately my scooter will be curbed for Memorial Day weekend....

[Cruiser]

Welcome to Scooter Doc, jaberwillow. Sorry to hear about no scootin' for the holiday weekend. A misconception about these pumps is that they are vacuum pumps and work best with a good strong vacuum. They are really pulse pumps and depend on changing or varying values of vacuum to pump. Used primarily with single cylinder engines because they do no have a very smooth vacuum when they are running. Applying a steady source of vacuum when testing these pumps will not make them pump. You have to have very good (thick walled and short) vacuum lines to get the best performance. These pumps tend to pump less at higher rpms because the vacuum tends to be smoother.

These pumps are generally connected to use the pressure pulsations found in the crankcase. This is a better application as crankcase pulses increase with engine speed.

[jaberwillow]

When I get the new fuel pump I am going to change all the gas lines because the one's from the factory are crap! I am just glad the scooter crapped out 1/2 mile from home! Was a pain in the butt walking it back home.....Thanks for your input! So you say the vacuum line should be short and thick walled?? Will look into that!

[Cruiser]

Use the shortest lines possible and the heavier tubing will transmit the pulsing better. Long thin vacuum lines tend to dampen the pulses.

[jaberwillow]

I want to thank you so much for the info on the vac line! I didn't wait for the new fuel pump to come and decided to change the gas line & vac line to a heavier line.....and wala! Turned out the vac line had a pinhole in it! Thanks for your help you have definitely made my day and holiday weekend!

[jaberwillow]

Still running fine! So it was the Vac Line Replacement to a thicker shorter line!

[Cruiser]

That's great, jaberwillow. May you have many happy scootin' miles and keep in touch.

[jaberwillow]

Oh well I guess I talked too soon! Bike ran fine since I changed lines, put 100 miles on it and crapped out today 3 times doing 50 mph....finally had to abandon ship...wouldn't start...ran battery down constantly trying to start it...still patiently waiting for place I bought scooter to send a new replacement fuel pump.....Picked Scooter up tonight after a serious thunder storm ran through and loaded her on the truck and took the broken baby home! Quite frankly I am almost done with CHINESE CRAP!!!!!!!! HELP???
Well much to my surprise...almost 2 weeks later I finally got my new fuel vacuum pump....installed it and I am riding once again! Yeah! Hope nothing else goes wrong! I would just like to enjoy riding my scooter for the summer!