Post by HotStuff2 on Apr 16, 2012 10:10:45 GMT -5
I posted this on another forum (unsure if it's OK to say which one, so I'll not for now), but I'm not getting anywhere, and I need help. 
Here's the deal:
I have a Taotao CY150-A 150cc, which I bought on April 1 *very* slightly used (had 413Km on the clock), and I'm now up to just over 928Km.
1. ORIGINAL PROBLEM: Scooter died on side of road on April 4; replaced spark plug with NGK CR7HSA + new spark plug boot. Still wouldn’t start or idle.
2. After leaving scooter at the shop for 4 days, it started normally and ran fine; took it home. Replaced the fuel filter with high-quality one from the shop (also lengthened the hoses to make it easier to get to, but that shouldn’t cause an issue, no?)
a. There was one hose from the gas tank that went to nothing (was just hanging there); I took it off, but again, if it went to nothing, that shouldn’t cause anything, no?
3. Roughly ~1 week later (this past Friday), sitting at stop light, scooter died again. Was able to get it started, but would not idle (had to rev engine to keep it running), and was very sluggish at take off.
4. Got it home, checked spark plug (which was 9 days old) – very fouled, engine appears to be running WAY too rich. Unable to adjust A/F micture (screw is not there, just a brass cap, Taotao apparently capped it permanently?)
5. Checked valves (next morning when cold): intake & exhaust were completely closed. Set intake to .004 and exhaust to .004
a. Checked valves again the next morning (again when cold); intake was good (still .004), but exhaust was back to closed. Re-set exhaust to .005 (tight.)
6. Finally was able to get it started, but still wouldn’t idle properly.
a. When started, the engine revs very high UNLESS I hold the rear brake (which stops the rear wheel from spinning), and then it idles somewhat normally. Releasing the rear brake = very high RPMs & rear wheel spinning very rapidly.
7. After ~10 minutes of warm-up (enough time for the auto-choke / fuel enricher to shut off), the engine idles very slow and will stall. Attempting to adjust the idle screw does not help.
Also, there is a hose from the carb that appears to be a fuel exhaust; it will occasionally have a fairly large amount of fuel spill from it. This shouldn't not happen, correct?
Possible issues:
• Bad fuel pump?
• Vacuum lines routed improperly? Tech at the shop took off the CA emissions control and re-routed the lines; perhaps one or more is incorrect? I don’t know how to check that.
• Carb fouled? Carb jets not correct?
• Compression issue? (May need to check valve clearance again?)
• Fuel lines may need replacing? (Some websites state that the cheap Chinese lines break down easily and may clog things up.)
• Jet needle may need to be be adjusted to lean out the carb some? (If adjustable)
• CDI bad? (Planning to replace it with one that removes the rev limiter + advances the timing anyway.)
Just guessing here on the possible issues, based on reading the GY6 shop manual and searching online.
I was able to start it and drive it to the shop this morning, although I have to keep the engine rev'ed or else it will stall out. Unfortunately, they're so backed up, I had to set an appointment for next Tuesday.
Here's the deal:
I have a Taotao CY150-A 150cc, which I bought on April 1 *very* slightly used (had 413Km on the clock), and I'm now up to just over 928Km.
1. ORIGINAL PROBLEM: Scooter died on side of road on April 4; replaced spark plug with NGK CR7HSA + new spark plug boot. Still wouldn’t start or idle.
2. After leaving scooter at the shop for 4 days, it started normally and ran fine; took it home. Replaced the fuel filter with high-quality one from the shop (also lengthened the hoses to make it easier to get to, but that shouldn’t cause an issue, no?)
a. There was one hose from the gas tank that went to nothing (was just hanging there); I took it off, but again, if it went to nothing, that shouldn’t cause anything, no?
3. Roughly ~1 week later (this past Friday), sitting at stop light, scooter died again. Was able to get it started, but would not idle (had to rev engine to keep it running), and was very sluggish at take off.
4. Got it home, checked spark plug (which was 9 days old) – very fouled, engine appears to be running WAY too rich. Unable to adjust A/F micture (screw is not there, just a brass cap, Taotao apparently capped it permanently?)
5. Checked valves (next morning when cold): intake & exhaust were completely closed. Set intake to .004 and exhaust to .004
a. Checked valves again the next morning (again when cold); intake was good (still .004), but exhaust was back to closed. Re-set exhaust to .005 (tight.)
6. Finally was able to get it started, but still wouldn’t idle properly.
a. When started, the engine revs very high UNLESS I hold the rear brake (which stops the rear wheel from spinning), and then it idles somewhat normally. Releasing the rear brake = very high RPMs & rear wheel spinning very rapidly.
7. After ~10 minutes of warm-up (enough time for the auto-choke / fuel enricher to shut off), the engine idles very slow and will stall. Attempting to adjust the idle screw does not help.
Also, there is a hose from the carb that appears to be a fuel exhaust; it will occasionally have a fairly large amount of fuel spill from it. This shouldn't not happen, correct?
Possible issues:
• Bad fuel pump?
• Vacuum lines routed improperly? Tech at the shop took off the CA emissions control and re-routed the lines; perhaps one or more is incorrect? I don’t know how to check that.
• Carb fouled? Carb jets not correct?
• Compression issue? (May need to check valve clearance again?)
• Fuel lines may need replacing? (Some websites state that the cheap Chinese lines break down easily and may clog things up.)
• Jet needle may need to be be adjusted to lean out the carb some? (If adjustable)
• CDI bad? (Planning to replace it with one that removes the rev limiter + advances the timing anyway.)
Just guessing here on the possible issues, based on reading the GY6 shop manual and searching online.
I was able to start it and drive it to the shop this morning, although I have to keep the engine rev'ed or else it will stall out. Unfortunately, they're so backed up, I had to set an appointment for next Tuesday.
