Author Topic: Kymco UXV 500 - No Spark Carb model  (Read 2035 times)

dbardell

  • Newbie
  • *
  • Posts: 9
    • View Profile
Kymco UXV 500 - No Spark Carb model
« on: October 10, 2018, 03:35:35 PM »
This thing is driving me nuts.  Starts and runs fine for awhile, then shuts off.  Will not restart.  Let it sit overnight, and it will restart.

Last time, it sat idling for about 3-4 minutes and shut off, Checked and no spark.  Tried spark plug and no help.  Any sensors that will prevent this from starting that I can check ? 


CROSSBOLT

  • Hero Member
  • *****
  • Posts: 7763
  • West Tennessee, USA
    • View Profile
Re: Kymco UXV 500 - No Spark Carb model
« Reply #1 on: October 10, 2018, 04:59:48 PM »
What tests have you done?
Karl

Three motorcycles 1960-1977 (restored a 1955 BSA)
Agility 50
Yager 200i
Downtown 300i
Navy tech, Ships Engineer, pilot and aircraft mechanic

dbardell

  • Newbie
  • *
  • Posts: 9
    • View Profile
Re: Kymco UXV 500 - No Spark Carb model
« Reply #2 on: October 11, 2018, 12:16:36 PM »
Just the normal stuff.  Engine turns over fine.  Changed spark plug, checked wiring to coil.  Seems to quit when it is warm.  I was thinking maybe a high water temp shut off sensor, but not sure it it has anything like that.  But does lose spark when it quits. 

CROSSBOLT

  • Hero Member
  • *****
  • Posts: 7763
  • West Tennessee, USA
    • View Profile
Re: Kymco UXV 500 - No Spark Carb model
« Reply #3 on: October 11, 2018, 01:53:13 PM »
Humor me: how do you know it loses spark when it quits?
Karl

Three motorcycles 1960-1977 (restored a 1955 BSA)
Agility 50
Yager 200i
Downtown 300i
Navy tech, Ships Engineer, pilot and aircraft mechanic

Louder North

  • Full Member
  • ***
  • Posts: 117
    • View Profile
Re: Kymco UXV 500 - No Spark Carb model
« Reply #4 on: October 11, 2018, 04:33:22 PM »
If it quits when it is warm, it could be a problem with the stator - small cracks become big ones when it warms up.  You can check it by measuring the output when cold and see if it changes when you point a hair dryer at it. 
2009 Kymco Frost (aka Yager 200i)
10,000 km
bought used in 2018
2007 Aprilia SR50 (Morini motor)
2013 Aprilia SR50 (Piaggio motor)
1986 BMW R80

dbardell

  • Newbie
  • *
  • Posts: 9
    • View Profile
Re: Kymco UXV 500 - No Spark Carb model
« Reply #5 on: October 11, 2018, 11:29:55 PM »
Humor me: how do you know it loses spark when it quits?

Pull spark plug wire and connect a good - new plug.  Ground on engine and try to start.  Original plug is left in head. No spark.  Yes, I have the engine cover removed. 

CROSSBOLT

  • Hero Member
  • *****
  • Posts: 7763
  • West Tennessee, USA
    • View Profile
Re: Kymco UXV 500 - No Spark Carb model
« Reply #6 on: October 13, 2018, 12:03:33 AM »
Good answer. Louder North may be on to something since the "pulsar" is part of the stator. Any way to set up measuring for the service manual resistance of the pulsar coil when the spark fails?
Karl

Three motorcycles 1960-1977 (restored a 1955 BSA)
Agility 50
Yager 200i
Downtown 300i
Navy tech, Ships Engineer, pilot and aircraft mechanic

hypophthalmus

  • Hero Member
  • *****
  • Posts: 598
    • View Profile
Re: Kymco UXV 500 - No Spark Carb model
« Reply #7 on: October 15, 2018, 04:50:00 AM »
Failing ignition coils can also be heat sensitive.

scooterfan

  • Hero Member
  • *****
  • Posts: 764
  • Durban, South Africa to Ankeny IA.
    • View Profile
Re: Kymco UXV 500 - No Spark Carb model
« Reply #8 on: December 11, 2018, 06:45:43 AM »
I experienced an exact similar problem on my 125 Agility. Eventually discovered that the CDI was causing the problem.
I initially saw a comment by someone who mentioned that a CDI just dies, and the engine will not start again. To my experience a faulty CDI does not behave like that.
When the CDI is on it’s way out, the engine start switching off suddenly during a ride, and will start again after a while. The engine switches off more regular as time goes by, but always starts after a while. Untill the CDI finally dies.


http://www.kymcoforum.com/index.php?topic=27442.0


« Last Edit: December 11, 2018, 08:25:04 AM by scooterfan »
Life is a journey. Just spend some time, and enjoy the trip.

An Error Has Occurred!

Call to undefined function split()