Tao Tao 150 wont idle/just dies By lawless211 (Read 6,162 times)

[lawless211]

I have a tao tao cy150 and having an issue with it dying as soon as i release the throttle.  I just upgraded the fuel/air hoses with helix hoses, put in a good spark plug, charged the battery, and even put a new carb in. After doing this, everything was acting the exact same as before, so im not sure whats going on. I am also getting a hesitation when I start her up and then it takes about two minutes of hitting start and turning throttle multiple times. I wish I could upload audio because the sound seems pretty odd and would think someone thats been around scooters would have a good idea of where to start.  I adjusted the valves to .003 and .004.

The other post pointed to air/fuel ratio but the problem is right away and is acting the same with a brand new carb. I am pretty new to all of this and there seem to be some knowledgeable people here. I came across this site when reading a similar thread, but seemed different enough to write my own.  Ive done more research and reading the past few weeks and have learned a lot and I am glad I made all of those changes, but I am now lost and am pretty desperate to get this running well again. The only local scooter repair shop is where I got the scooter and know I will be over charged. Please help. 

[JR]

If you make a you tube video it'll have sound and they can be uploaded here with no problems. Have you checked the compression on it? Hearing what it is doing would be helpful.

JR

[lawless211]

Here is a clip of me trying to start it. Like I said, if I do this for a little while, I can get it running, but will die as soon as I let off of the throttle.

[lawless211]

JR Did you get a chance to listen? I went through pages 11-40 in this class and read any thread that seemed similar to mine and haven't really found anything solid. I would love some expert advice being a new student. Thanks,

[JR]

lawless211

In the above video it's obvious you have a nearly dead battery. Need to charge it at a slow rate 1 to 2amp charger for 5 to 8 hours, if it continues take the battery to a local auto parts store and have it tested. If it tests badly then replace the battery. In your video it appears there is not battery in the battery box, are you jumping it from another source?

JR

[lawless211]

JR

I recently charged it. I plugged it in to a trickle charger last night to check again and it was not long at before it said it was charged. I did some more work last night and tighted some areas around the carb to make sure there weren't air leaks and I got it started the best I have in awhile. I set the fuel ratio screw and then using the idle screw, but it would still die if I let throttle go even when i was turning idle screw. Shortly after this, I recorded this video of me trying to start it again with no luck.

[JR]

Ok if it did run then we know it had ignition spark and fuel but the way it sounds now it seems it's getting no fuel. So like with all gremlins finding out what is wrong is a process of elimination. So I'm going to give you some things to check.

In the video where it is not even trying to start do you smell gas? Reason I ask this is if for some reason it now doesn't have a sparkplug spark then after turning it over you would smell the gas like the engine was flooded? But if you know how to test it for spark do so just to eliminate this possibility and when checking the spark one wants a nice blue hot looking spark, not a orangish weak looking spark. Video section on spark testing:

thescooterprofessor.proboards.com/thread/4167/electrical-check-spark-tester-method

Now if you have a good spark then we need to move on to the fuel situation, does it have a fuel pump or is it a gravity flow system with the tank above the carb and does it have a vacuum fuel cutoff petcock? You mentioned when you tightened things up around the carb it ran better so if it has a fuel pump or even a vacuum fuel petcock and you have vacuum leaks this is going to not only cause carb issues but fuel delivery issues as well. If it's starving for fuel it'll run like crap. Let me know the answers to these questions and if you're not sure open it up and take pictures to post.

JR

[lawless211]

JR

There is definitely a good spark. I think you could be right with something with petcock or somehow not getting fuel. My tank is up higher than the carb, but I believe it is a vacuum fuel petcock. Here are some images of it.




I don't think there are any more gaps or air leaks, but what do you think? Here is the latest video on me trying to start it. I once again got it to start once or twice, but mainly getting this.

[JR]

That is for sure the vacuum fuel petcock.





Now here is how to test it. Unhook the fuel line to the carb and the vacuum line to the intake manifold. If you have nay kind of syringe you can put that on the vacuum line and pull on the syringe plunger and if the fuel petcock is good it will open and fuel will be flowing from the fuel line. If you don't have a syringe you can use your mouth to suck on the vacuum line which will do the same thing.

Also I still believe you have a weak battery. Would like to hear the sound of it turning over with it fully charged?

JR

[lawless211]

JR

Petcock is working well. Taking battery to get checked out now or buying new one. Besides that, what next since petcock is working?

[lawless211]

JR

The battery was no good. I got a new one and I am charging it now. I will update after it is charged.

[JR]

Cool and then we'll go from there.

[lawless211]

JR

Starting sounded better with new battery, but still took awhile to start. Died once I released throttle. 2nd time I tried to start it, there was a clank sound right at first and then it continued what it was doing. I would describe the sound like a pencil being put into a small fan.

While it was running, there were air bubbles moving up the gas hose. Is that normal or is that saying that the gas isn't being pulled through very well?

Here is a video of the gas line while it's running. You'll see the back wheel stop spinning which is when I release the throttle and then you will hear it die.

[JR]

lawless211 Does the fuel filter have a direction flow arrow on it? To me the fuel filter appears backwards? No you shouldn't be getting air bubbles in the fuel line in fact I don't even know how air could get in the fuel line unless there is air in the tank or it's being pulled in from the fuel petcock someway?

When you tested your fuel petcock did you get a nice steady flow of gas or just a trickle? This is a fuel problem for sure and even though you bought a new carb that doesn't mean there is not issues with it? So it will not idle unless you hold the throttle and give it gas?

I'm going to holler at a friend for some help with this problem.

JR

[cyborg]

Fuel filter is installed backwards,,,I know you have adjusted the valves,,,I think you may want to look at them again ,they could be tight