Author Topic: Mongoose 90 riden, parked, and now no spark???  (Read 3387 times)

Border411

  • Newbie
  • *
  • Posts: 3
    • View Profile
Mongoose 90 riden, parked, and now no spark???
« on: January 26, 2020, 01:51:33 PM »
Ok peeps.... Braintrust time. I rode my daughter's Kymco ATV 2 months ago. Put it in the shed in the back and let it sit on the trickle charger. Went to start it today.... Wouldn't start. Fuel preserver was in it. Pulled the plug.... No spark, but was wet from fuel. Also tried a new plug and grounded it with the same results. Checked all the wire connections and everything looks clean and good to go. Coil is within specs. Battery is charging to perfect voltage. Thoughts? What the hell would have changed in that time frame just sitting there? I'm thinking corrosion somewhere on a wire. Got a service manual and I don't have a way to test the CDI (no specs). I have a tether/plunger type kill switch, and I don't get a spark with it in or out, however the engine will turn over even with it out????? Does that just kill the spark, or do they usually stop the starter from turning over as well? It is the same ATV, essentially, as the Kawasaki KFX90 and Suzuki 90.

CROSSBOLT

  • Hero Member
  • *****
  • Posts: 7721
  • West Tennessee, USA
    • View Profile
Re: Mongoose 90 riden, parked, and now no spark???
« Reply #1 on: January 29, 2020, 09:22:20 PM »
Is there a run/stop switch on those?
Karl

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

manny77

  • Newbie
  • *
  • Posts: 1
    • View Profile
Re: Mongoose 90 riden, parked, and now no spark???
« Reply #2 on: April 19, 2020, 11:34:44 PM »
@CROSSBOLT - did you ever get this resolved?

I am getting what sounds like the exact same issue on my Mongoose 300.  I also went through basically the same steps; spark plug was wet went it was pulled.  No spark when grounding.  Tried new spark plug with the same results.  Tested the coil and getting 3.1 resistance between the positive and negative plug (seems borderline to me, does anyone know if this is an acceptable range for this ATV?) and 19k resistance between the positive plug and the spark plug cap.  Followed all the wires and all look good with no fraying anywhere.  I also checked all fuses and they were fine.

At this time I am leaning towards it being a bad CDI. 

Does anyone have a good way to bypass or check all the kill switches to make sure this is not an issue before I fork over cash for a new CDI?  I read you can cut one of the wires that goes to the CDI to bypass the kill switches but I am not sure which one it is.  Also does anyone have a good way to test the CDI?

jbuffum1

  • Newbie
  • *
  • Posts: 1
    • View Profile
Re: Mongoose 90 riden, parked, and now no spark???
« Reply #3 on: February 06, 2021, 10:09:45 PM »
Did you guys resolve your issue with your Mongoose?  I have a Mongoose 90s for my daughter i bought new in 2019,  barely has 20 hours I bet.   Same thing happened to me.  I was riding, I parked it, then it wouldn't start.  I was able to get it to start once or tice but now it hard over dead.  Turns over but no spark.

I narrowed it down to the CDI.  I found specs online  for it here https://www.manualslib.com/manual/1386957/Kymco-Mongoose-90.html page 239.

It says it should be roughly 5 ohms from Black, black/yellow, and blue yellow to greeen.  I measure open on all three.

My problem is finding the correct replacement.  The sticker on it say "30400-PTA7-900".  I can't find it anywhere.  I have found ones that look like it but do not say they are for the mongoose 90s.  It also has an 8 pin connector which is unlike most of what comes up in the search. 

If you guys know a reliable parts replacement site that would help. 

An Error Has Occurred!

Call to undefined function split()