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Scooters - 50cc => Super 8 => Topic started by: bahiano on August 24, 2011, 07:38:38 AM

Title: Scooter dies when i stop - Help
Post by: bahiano on August 24, 2011, 07:38:38 AM
Dear all,

did anyone else have this symptom? My 50 cc 4-T Super 8 has only 1000 KM on the meter and always dies
whenever I have to stop somewhere. I tried everything like cleaning the carb, checking vacuum hoses,
Valve clerance, Spark Plug. Even if i higher the idle speed, it will fall again automatically, air/fuel screw is put to factory adjustement.
This happens only when the engine is really warm. No other symptoms so far, it
runs smoothly until top speed. I am guessing it could be the CDI… but I am really going crazy  >:( as warranty period is
also over…
Any help would be highly appreciated...

Sorry for the mistakes as I am from Germany  ;D
Title: Re: Scooter dies when i stop - Help
Post by: thebatman on August 24, 2011, 11:15:44 AM
 ??? This may be a long shot but it sounds sort of like the "choke" is still on and richening it to much...(the auto-enrichener) or that the pilot system in the cArb is partially closed.. Check the pilot jet,etc. again
Title: Re: Scooter dies when i stop - Help
Post by: bahiano on August 24, 2011, 11:21:57 AM
Thanks a lot, i will try it.
Today i will replace the CDI and see if it will do the trick. Otherwise i will have to start all over again  :(

Cheers Markus
Title: Re: Scooter dies when i stop - Help
Post by: bahiano on August 24, 2011, 07:17:42 PM
Hi all,

the CDI unfortunately did not fix it.

@batman: What do you mean by pilot system? Sorry my english a little poor  ;) The jets i already cleaned....

Any suggestion is welcome...
Title: Re: Scooter dies when i stop - Help
Post by: JustWantToRide on August 24, 2011, 11:03:37 PM
I believe he meant the pilot jet in the carburetor.

Do you have the service manual?  Section 5 starts out with instructions for testing the auto enriching circuit.  If you haven't tested it - then that is what I would look at.  The manual calls it a "bystarter".  Once you get used to the odd translations - then the manual is very helpfull.
Title: Re: Scooter dies when i stop - Help
Post by: bahiano on August 25, 2011, 04:12:58 AM
I already changed the auto-enrichener, still the same problem...
Thanks so much anyway
Title: Re: Scooter dies when i stop - Help
Post by: JustWantToRide on August 25, 2011, 06:39:47 AM
Da passiert es nur, wenn es heiß ist - ist es überhitzung?  Die Lüfter laufen?  Wie funktioniert die zündkerze aussehen?  Ich denke, es läuft zu reichen, und die apark plug wird dunkel.
Title: Re: Scooter dies when i stop - Help
Post by: bahiano on August 25, 2011, 06:45:55 AM
Yes, it only happens when engine is hot! Fan is working... I check the Spark Plug, looked ok so far...

Dein Deutsch ist sehr gut  :D
Title: Re: Scooter dies when i stop - Help
Post by: bahiano on August 25, 2011, 08:12:10 PM
i cleaned the carb again, tested the auto-enrichener, changed the spark plug (the old one looked quite dark).... Still i could not
adjust the carb, idle cannot maintain and it dies again  ??? ??? I even checked ignition system with the Ohm-Meter, everything ok as per manual values....
Ok now i am done and dont know what else to do :(
Any ideas? Feel like givin up and selling it  >:(
Title: Re: Scooter dies when i stop - Help
Post by: JustWantToRide on August 25, 2011, 08:49:15 PM
Vielen Dank, werde ich nicht mehr in die Praxis meiner Deutschen viel mehr.

Es läuft zu reichen. Öffnen Sie das air box, entfernen Sie den filter, und stellen sie sicher, dass sie gar nichts blockieren die Luft. Starten sie ihn mit der airbox noch offen und keine filter.

Wenn es läuft - dann prüfen, ob die filter ist erstickt - oder wenn der vergaser es stranguliert.
Title: Re: Scooter dies when i stop - Help
Post by: bahiano on August 25, 2011, 08:54:47 PM
Ok vielen Dank, werde es morgen versuchen...
Thanks and Gute Nacht!
Title: Re: Scooter dies when i stop - Help
Post by: bahiano on August 26, 2011, 04:17:54 PM
Ok i tried as you said, it seemed a little better, it did not die, but i could not adjust the carb the same. Idle speed only raises when i close the air/fuel screw, or when i
nearly reach the closing point. What can that symptom be? I thought it would no run at all with the air/Fuel Screw closed  ???
I think i will bring it to the dealer and let him go crazy with it :(

Cheers Markus
Title: Re: Scooter dies when i stop - Help
Post by: JustWantToRide on August 26, 2011, 04:35:00 PM
I could be a weak coil - but I would think it would not idle with a weak coil. 

It isn't able to burn the fuel it is getting.  I think you have missed something in the carburetor.  Either a jet is clogged, the needle is in the wrong position, or the float is not adjusted properly.   
Title: Re: Scooter dies when i stop - Help
Post by: bahiano on August 26, 2011, 04:38:25 PM
ok i think i will try to get a new carb... is the one with the "metal top" in ebay ok? Are they all the same? We can get them here in eBay quite cheap for
chinese scoots...
Title: Re: Scooter dies when i stop - Help
Post by: bahiano on August 28, 2011, 04:51:30 PM
ok i cleanes all jets again with air and they are all clean. Still the same symptoms, i cannot adjust the the carb, when i close the air screw, the idle speed
raises instead of dropping... there seems to be a change only when closing the air screw :( opening it, no reaction from the idle speed....
I am no really out of things to try...  :-[
Thanks everybody anyway...
Title: Re: Scooter dies when i stop - Help
Post by: bahiano on August 29, 2011, 07:09:56 PM
Ok everybody, i think i found the mistake, i checked the voltage that arrives at the auto-enrichener and i found nothing. There is the black wire and the green/yellow one. I checked the black one against ground and i had 12 Volts. So the green/yellow cable was not connected to ground (-). I connected a new cable to the auto-enrichener and grounded it at the frame. Now it runs like a V8 muscle car :)

Thanks everybody, at least now i know my scooter in detail  ;D

Markus
Title: Re: Scooter dies when i stop - Help
Post by: JustWantToRide on August 29, 2011, 08:09:47 PM
 8)  Glad you're back on the road!
Title: Re: Scooter dies when i stop - Help
Post by: bahiano on August 29, 2011, 09:05:42 PM
Apprecciate it  ;D
Now the 72cc project can start  ;)