I have a coolster 150cc with a gy6 engine. I cannot get it to run excpet for when I put gas into the cylinder and of course it stops running 3 Seconds later. It needed a new carb and ignition coil. I have accurate fuel through the carb now and spark. The intake has one brass nipple I'm assuming it's a vacuum line. I have my hoses hooked up corrcetly I believe. But I cannot figure out now what's wrong. Anyone can help I'll try it! Thanks

 

Adjust the valve clearances. If that doesn't work, check compression, it should be at least 100psi. If that is OK clean the carb out. (Yes I know it is new) and check the jets etc, are the same as the old one.

 

Thank you for the ideas. I will try them. The carb either not being jetted correctly or the float stuck crossed my mind after reading on more forums alothough it's new. The only question I have before I get into the valves is wouldn't the engine start with gas in the cylinder if the valves need adjusting? I was under the impression direct fuel into the cylinder invaded a fuel problem with the carb.

 

If the valves are out of adjustment the engine wont be able to pull fuel into the engine. So yes with bad valve adjustment the engine would still run when you put gas ion the cylinder. Id try turning the quad on its side and see if fuel comes out of the over flow hoses on the carb.. if it does.. fuel is in the carb..

 

Yes there is fuel to the carb when I tip it on its side. I am going to take your advice and look at the valves today. I wouldn't be shocked if you end up being right. The quad sat for many years until I decided I wanted to use it again. That's why I had to rebuild the stock carb even bought a new one for electric choke issues. Ignition coil new battery and spark plug. I have tested all of my connections and replace all the fuel lines bc they cracked and rotted. I was told that when a machine sits like this for years the valves on the engine with tend to tighten or loosen and may need adjusting. So I will be checking this today. Not sure on how much of a turn or adjustment they will need. But I'll use a feeler gauge to see if I have drag or not. Thanks I really apprecaute your help. I'll let you know what I come up with.

 

You were right. Sure enough took the cyclinder cover off and the intake valve was to loose where the exhaust valve was completely compressed. I set the intake to 0.005 and the exhaust valve to 0.005. And she started. Problem I'm having now is when it's idling or driving it is super smokey looks like I'm running a 2 stroke. This means I'm running to rich correct? To much fuEl not enough air? And they way to adjust this is the fuel n air mixture screw on the carb?? Anyone that knows please respond.

 

The fuel screw will let more fuel in as you open it...You want to close it.. Id start at 1 to 1 1/4 turn out (from turned in until it stops) and go from there...

 

I went down to my barn to do just what you said. And for some damn reason I blew the ignition coil I just bought. It has no spark again. Tested then plug on my son's 90 and plug as spark. Only had this coil now for a week. Idk why I burnt out that coil. Maybe it's time to chance the cdi? What do you think? You have been right all along so far.

 

With regards to the smoky engine, I'm sorry My wifes quad but I don't think laying a bike on it's side is a good idea, as oil tends to get where it isn't supposed to. Check you haven't filled the air filter box with oil. Oil smoke smells quite different to excess fuel. If it is fuel, you get that "on choke" smell and if it is enough to smoke, the main jet will need adjusting, probably by lowering the needle in the slider.

Chinese electrical components are not best quality so a coil that lasts a week is a possibility. I've never known a CDI burn a coil but you never know.

Just had a thought, if it is running rich or with excess oil it could just have sooted the plug, they can still spark, but it is too weak to fire the mixture.

 

Your kidding I hope. What happens when a dirt bike falls over on its side while riding it?

Ive been laying dirt bikes on their sides for about 40 yrs to get bad fuel out of the carb.. and to check for stuck floats.. It was also a good way to get 500cc 2 strokes running (before kick starting them when cold)