Build Number 3. Engine won't fire?

[evilball]

So, this is my third build. I'm using a random cruiser frame and an old engine that I pulled off a friends bike when I rebuilt his motor bike. I changed the cylinder body and piston as well as replaced the muffler and gasket, carburetor, and spark plug. I had it running and took it out around town. I stopped and turned it off for about an hour. When I tried to start it again, it wouldn't run. I should note that during the ride it blew the exhuast gasket because the nuts had come loose. I have since replaced the exhuast gasket, cdi, and magneto coil. It still won't run. I have checked everything I can think of. I suspect its not pulling fuel into the engine, but I'm not positive.

Is there anything you can suggest, my fellow gearheads, or should I just get a new engine?

 

[Dan]

Howdy EvilBall welcome.

If it is an old tank, would check/clean the carb.
Would post in the in the 2 or 4 stroke section, depending on which you have. You'll get a lot more thoughts.

 

[evilball]

Thanks, will post there soon. The carb and main tank are new. I have two tanks. Except for the reserve tank and the engine itself, everything is new. I did completely dismantle and clean the carb though, to no avail. I even reran the fuel lines. I'm baffled.

 

[dragray]

new parts doesn't always mean good parts.
it's possible that your float is stuck in the up position not allowing gas to flow into the float bowl.
the petcock could be plugged up with debris inside the tank.
pull the spark plug and verify that you have spark. sometimes you can have spark, but it won't be strong enough to fire the fuel.
shoot a tiny bit of starting fluid into the carb and see if it will fire.
if it fires, you have a fuel delivery problem, or possibly a bad spark plug.
if your using the stock china spark plug, throw it out and get an ngk.