Scooter starts, then stalls By canerican (Read 2,571 times)

[cyborg]

i concur alley it is varnished jets and ports,,,almost a year,,,,with a certainty this is the problem

[canerican]

Great, thanks everyone.
Since I have the scooter taken apart, I'm thinking I should also adjust the valves to 0.03. I'm not quite sure how to find TDC, so I'll look that up before I do it. I know there are posts on adjusting the valves, so I'll read through those instead of asking for hints and pointers here.

[Alleyoop]

Take the valve cover off and line up the CAM SPROCKET like in the picture and adjust both valves to .003 inchs:
Alleyoop

[canerican]

Thanks Alleyoop. I had found a similar post, but I'm glad for the confirmation.

I took the carb apart again last night, but sprayed cleaner through the ports this time. Turns out that was the main problem, and the scooter is starting, idling and revving now.

When I first got it started, it was burning some oil, as evidenced by the smell and blue smoke. I'm hoping that this is because it sat unused for a long time, but I'm not certain. Should I be concerned about this, or wait and see? What should I do about it, if anything?

It's also still idling really roughly, and it seems like it's mis-firing or something. I'm going to adjust the valves tonight, and hope that fixes the problem. Either way, I'll post a follow-up tonight or tomorrow.

Thanks again everyone.

[Alleyoop]

Glad it was just dirty passages and not getting fuel. Since it is burning some oil take the plug out it may be fouled and that will cause mis-firing and the rough idling.
The oil burning if it keeps it up then that would be the rings, but since it sat for so long it may go away.
Alleyoop

To smooth out the idling adjust the carbs fuel ratio mixture:
scooterdoc.proboards.com/thread/1499/4ts-carb-tuning

[canerican]

OK, thanks Alleyoop.
I just replaced the spark plug, so I'm hoping it's not fouled already. I'll check it when I adjust the valves tonight (since I have to take it out anyway).
I adjusted the fuel ratio mixture last night, after I got it running. It got a little better, but I realized today that I didn't run the engine long enough, so the enricher was probably still engaged when I was adjusting. I'll do it again (properly) tonight.

[canerican]

Update:
I adjusted the valves tonight. The top was already at 0.003, but the bottom was almost all the way closed. I set it to 0.004.
I checked the spark plug, and it looks fine. No black deposits or anything that would imply it was fouled. The engine does still burn some oil when it first starts though. I'm still hoping that gets better as it gets used more. If not, I'll have to figure out how to order the right rings to replace them.

I then started it and it seemed a little better. I let it run until the rpm's dropped, indicating the enricher had disengaged/auto-throttle was fully extended. I adjusted the idle so it was idling steady, and then started to adjust the fuel ratio mixture. I adjusted it a small amount, and then let it steady out, and repeated until I got what seemed to be the highest rpm's and most stable idle. The deciding factor ended up being the engine skipping. It would idle fine, but then every 20-30s it would skip. I adjusted it until it didn't skip anymore...
Is it possible that the fuel ratio is the reason it would be skipping, or is there something else I should check?

Thanks again.

[Alleyoop]

Did you check the gap on the plug, it should be gaped .27-.28, It may be gaped to wide, also check the wires going to the COIL if loose give them a little crimping.
Alleyoop

[canerican]

Spark plug is brand new, so I didn't think to check it. I'll do that.
The wires look pretty good, but some of the secondary covers are pretty worn out. I was going to get some high-temp wrap tonight.
I could take my meter to the wires, and check resistance and voltages. Will have to look up what the coil should be, though.
A lot of the wires look pretty old and worn, so I was considering re-doing them this weekend. Not sure if it's worth the effort or not, though. I'm going to be installing a 12v accessory plug inside the seat, and figured I'd work on the electrical stuff while I was at it.

[Alleyoop]

Just a suggestion if your going to do some wiring DO ONE AT A TIME Many go and unplug all the crap then they don't know which plug goes where.
Alleyoop

[canerican]

Good tip. Thanks!

Any suggestions as to what type/kind of wire to use? I was leaning towards 14-16AWG stranded copper, with standard plastic coating. Am beginning to wonder if the heat will cause problems, though.
I'll search the forum on this topic as well, though. Someone has probably already asked this question.]

EDIT: From what I can tell, it hasn't come up in a direct way. So, please weigh in on what kind of wire I should use. Thanks!