New Chinese scoot. After 5 mins dies. Restart dies [look] By stevef2223 (Read 316 times)

[stevef2223]

Just got this scoot, Taotao Roman 150cc GY6.

Starts up cold like a champ. No issues, runs fine.

Runs for 5-10 mins and then peters out and dies.

Attempt to restart is futile.

I have replaced and checked the following…

1. Carburetor: Replaced with new carb, same issue.

2. Valves: Adjusted valve clearances to .004 intake, .005exhaust.

3. Check spark plug. Looks good, No heavy deposits or not too white.

*Noticed semi-clear gas filter is only ¼ full. Not sure if only ¼ full gas filter has anything to do with this or not.

I “feel” that this is a warm up issues, after warmup / heat issue causing this.

Please advise oh great Chinese scooter masters.

[stevef2223]

Forgot to mention... the fuel in filter is where you see blue line. About 1/4 - 1/6 the total fuel filter.

And I have to wait for scooter to "cool" down until next day or few days for it to start back up again.

Or else I just get the starter trying but no turn over. The gas filter rises slightly then goes down.

[fflintstone]

Welcome steve2223, I am fflintstone,an old scooterist with some experience with engines and components and I can give an opinion but the real knowledgeable techs and wrenches will let you know what is happening--however ,until they get in ,I will tell you I think it is not a fuel problem but electrical --you have enough fuel to crank up at least,in the filter so it must be a heat related problem with a coil or stator --or maybe some vapor lock in the fuel line if I am wrong about the electrical thing--I once had a Ford that would run fine all day or short time no problem,but shut it off and it would not start up until the next day until a wise mechanic told me about the fuel pump vapor lock,caused by heat from a manifold pipe near it --and the vapor lock was caused by a malfunction of the diaphragm in the clunky old fuel pump,it would kinda warp and refuse to work until it cooled off--on the older cars you could pour water on the pump,and cool it--nowadays ,you can't even find a pump--so I think your problem is electrical---coil -stator-,ruined plug--try holding the spark plug wire away from the plug and crank it and see if it throws a spark --no spark,/problem --anyhow,welcome and some other members will be in soon and help out--good luck ,fflintstone ----btw---if you have another spark plug ,try it,it could be a problem with the plug--I had a gas mower that had a clean looking plug ,but somewhere it was bad ,wouldn't start,new plug solved the problem--cheapest way to start checking it out

[JR]

Is this a gravity fed fuel system with no fuel pump? If so then my thinking is you are not having the fuel petcock open all the way to it being bad, or a vacuum leak that is not letting it open all the way. If this is the case the carb bowl is running dry for lack of fuel. One can test this easily by removing the fuel line to the filter and then applying vacuum to the vacuum line to see if gas flows freely and a good steady stream. vacuum can be applied by using a big syringe or by putting suction on it with your mouth. Be sure to put something under the fuel line to catch the fuel.

JR

[crwford]

maybe just loosen gas cap see if it help a mount of fuel in filter ?

[Louis Angel]

" Or else I just get the starter trying but no turn over. "
The " but no turn over " part bothers me.
Will it turn over with the kick starter after it dies?
If so, you can open the drain valve on the bottom of the carb to see if the float bowl has fuel in it.
If it does, then I am thinking it is the ignition coil. When the coil heats up, the internal wiring gets hot and as copper expands what in turn is happening is there is a break in the windings inside the coil, causing loss of electrical current.
To test this, first get spare spark plug to take with you, run the scoot till the engine quits, when it does, pull the spark plug boot off of the plug, slip it onto the spare plug you brought with you, and turn the engine over while someone looks at the plug to see if it is sparking. Remember, the end of the plug needs to be touching metal on the scooter or it will not fire due to no ground.
ALSO, lol, , , I HAVE myself had spark plugs fail when hot. Well, one plug, one time. On a 12.5 HP Briggs & Stratton engine. But was the exact same process. Started like new when cold, 5ish min. into mowing the yard it would shut off. 2 hours later, would fire back up and run another 5ish min, then die again. Rinse - lather - repeat. lol
Mind you this was about 20 years ago. But spark plugs have not changed in 20 years. (basic plugs anyways ) Drove me NUTS for 3 weeks! I pulled & cleaned the gas tank ( per my uncles suggestion ). Replaced fuel lines & filter and rebuilt the carb per dads suggestion. Replaced Coil per shade tree mechanics suggestion. Replaced spark plug as last ditch effort, and VOLA!!!! $2.00 spark plug cost me many many many hours of labor and $60ish of not needed parts. DONT OVERLOOK THE EASY STUFF FIRST!!!! :-D