Misfire in the hole!

[rks]

Have you done anything with your fuel pump yet? Their diaphragms don't last forever....especially if you run an ethanol blended fuel, and 9 years is a long time.

Runs fine on the pilot jet.....crappy when the main kicks in, sounds like a restriction somewhere in the fuel system.

How is the new carb jetted, compared to the old one? Too much main jet will cause big problems when operating past half throttle also....but being a mechanic, I'm sure you're aware of this.

[XenoMorphicRex]

Since I started this thread, I have recently solved the misfiring problem. But a new one has cropped up. I did a test ride yesterday, and she purred like a kitten. I parked her in the garage overnight, and now I can get my scooter to start. The motor turns over, and she's getting fuel, because I smell it coming out of the exhaust. I thought "Ok she's either flooded, or there's no spark."...I pulled the plug out, and put a spark tester on the plug lead. and it's getting a good strong spark. Changed the plug again, thinking I may have a defective Plug, But it still sparked with a strong blue arc. So it's not ignition. I checked all my vacuum lines, because the fuel pump is vacuum powered. The pump itself is working, because I got a strong spray of fuel. The timing seems to be correct.

But this Chinese POS still won't Start. when it was running fine yesterday.

I'm dreading the next possibility, But Could it be Rings?
If so, This engine it mounted in such a way that I'll have to pull it out of the bike for tear down. I'm not afraid of the work, It's the expense I'm worried about. If its the rings, the cylinder may be scored, and pieces of Piston ring may be in the crankcase. Which all us mechanics know that this can utterly destroy an engine. If this is the case. then it will be a long time before I cant ride again. I've been out of work due to a back injury. and I'm on temporary disability, so money is not coming in at the moment.

[XenoMorphicRex]

It's an exact duplicate of the stock carb. she was acting like she wasn't getting enough fuel. Found out that problem was an air leak in the intake manifold. I replaced the manifold, and she ran like new, until today. Now I can't get Her to start. Look at my reply above for more details.