Jonway yy50qt starting problems By griffo (Read 2,901 times)

[griffo]

Had problems with my jonway scooter. It would not start and smelt of petrol I took the spark plug out gave it a clean and dried it out over a gas flame. Put it back in and it started no problem. Left it running with no issues. Turned it off and tried to start it a few hours laterno joy. Took the spark plug out and it was wet and black and smelt of petrol. Any ideas please

[Alleyoop]

Yes, your running very rich, First take the VACUUM line near the carb going to your PETCOCK or PUMP and see if it is WET. If it is WET it is drawing fuel from the VACUUM line and you need to replace the PETCOCK or PUMP.

If Dry then your Carb needs to be adjusted it is feeding to much fuel.
Alleyoop

ADJUSTING YOUR FUEL RATIO SCREW:

FOLLOW THIS PROCEDURE, take your time DO NOT Be turning the SCREW fast and wait in between turns otherwise you will be off.

Warm Up the SCOOT for at least 5 minutes.

YOU WANT THE HIGHEST IDLE OUT OF THE FUEL RATIO SCREW YOU CAN GET.

ADJUST YOUR FUEL RATIO:

1. Turn the Fuel Ratio Screw Counter Clockwise 1/4 and wait 10-15 seconds to allow the engine to catch up with the new setting.

** IF ON THE FIRST TURN IT DOES NOTHING OR IDLE GOES DOWN- GO to 2.*** Otherwise GO to a. below.

a. If the IDLE GOES up repeat 1.
b. If the IDLE does not go up or it does nothing turn the Fuel Ratio Screw 1/8 Clockwise that should be the highest IDLE you can get out of the Fuel Ratio Screw-- GO to FINISH UP.

2. Turn the Screw Back 1/4 and GO to 3..

3. Turn the Fuel Ratio Screw Clockwise 1/4 and wait 10-15 seconds to allow the engine to catch up with the new setting.

** IF ON THE FIRST TURN IT DOES NOTHING YOUR PILOT JET AND OR PASSAGES ARE CLOGGED*** GO to CLEAN CARB*** Otherwise GO to a. below.

a. If the IDLE GOES up repeat 3.
b. If the IDLE does not go up or it does nothing turn the Fuel Ratio Screw 1/8 Counter Clockwise that should be the highest IDLE you can get out of the Fuel Ratio Screw-- GO to FINISH UP.

FINISH UP:
SET IDLE USING IDLE SPEED SCREW:
USING the IDLE SPEED SCREW set the Idle to 1500-1800 where it IDLES the smoothest AND the REAR WHEEL IS NOT Spinning-

TEST YOUR ADJUSTMENT:
Now while on the Center Stand GIVE THE THROTTLE a GOOD QUICK TWIST and Let go,
It should REV UP with with a nice VROOOOOOOOOM with no Bogging or Hesitation and Come back down to where you set your Idle.
DONE RIDE SAFE.

CLEAN CARB:
Take Carb Bowl off and clean Pilot Jet and Pilot Jet Passage and Main Jet and Passage.
Then come back and repeat this procedure.

[kz1000st]

Silly question. Are you sure you have the right heat range plug? This also sounds like the classic stuck float needle. Two cures, maybe three. First, clean the carb-which I hate to advise. Second, Seafoam in the gas tank at twice the advertised rate. Third, bounce the scooter. I had a stuck float issue on a scooter so I ran down the road bouncing over raised asphalt lumps. Picking up the rear end and dropping it might help too.

[griffo]

The scooter has not had a good run for about 2 months I think. Had it running yesterday on tick over for about an hour. I wonder if it has a good run would that help it. My son can't do his test till march so plenty of time to sort it.

[jct842]

Worst case is just go buy a $25 carb on ebay like the previous owner of the 50cc scooter I bought last spring as a gift for a friend. I would be willing to bet I could take the old carb apart, clean it and would have a perfectly good spare and I probably will do that as I have the old one in the box the new one came in.