Rough running gas ez go

[jwicker068]

I'm baaaaaaaaaaaaaaaaak!. Alright, got fire to the plugs, the engine will now turn over (finally), but, it will not rev at all, and back fires through the carb. Now, this is a 2007 295cc robin engine, with a little over 600 hours on the clock. I have replaced the carburetor, igniter, pulsar coil, coil pack. The air gap on the pulsar coil has been set, I have set the valve lash to .004, and have installed new ignition switch. I am running out of ideas. It will fire right up, but stumbles, and if full throttle is applied, sounds like it is loading up, and will sometimes back fire. If it was a car, I would swear it is out of time. I have even tried without the choke being engaged at all, same problem. Stumped. Any suggestions? I am wide open for them. Thanks.

new spark plugs ? wires ?

[jwicker068]

New plugs (ngk) and new wires. Could it be the voltage regulator stealing voltage?

[nobuckbuild]

this is more a mechanical problem the electrical , check your compression , you have one of three problem , carb , headgasket or a valve that has beaten itself into the head

[jwicker068]

I checked the compression on both cylinders, and they in the 145 to 150 range. I replaced the carburetor with a new one, same result. I can turn the engine over while examining the rocker arms, and they seem to be smooth running, and no unusual play. I still wonder about the timing, but I know these engines to not have adjustable time. Stumped.

[nobuckbuild]

did you check the timing belt to make sure its not out of time ? also some of the new carbs can be doa about 50% of the time you may want to pull it apart and take a look , also out of the box the adjustments can be off , as well as these engines are super finniky about sealing the intake to the carb

[jwicker068]

Now I am really going to show how dumb I am. How do I insure the timing belt is correct? I have never fooled with the timing belt on these carts.

[RibbedGiraffe]

There are alignment marks. Ill see if I can dig up some pics and post them in a bit.

[jwicker068]

Alright, a little update. Seems the fuel pump has issues, and the fuel in the tank appears to be real stale. I am going to drain the tank, put fresh fuel in it, and replace the fuel pump. I think(?) that may be a large part of the problem, as the choke seems to have no effect when cranking or running. So, maybe a fuel starvation problem, and the back fire could be bad fuel/air in line due to faulty pump. We will see, however, I am still open to any other suggestions. Thanks.

[RibbedGiraffe]

Disconnect the fuel line from the carb, and crank the motor over. If the fuel pump is good, it'll pump fuel. Also, if the gas is bad, there is a good chance the carb could be goobered up as well.