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So My 07 Kymco Mongoose 300 was having a bit of choke issue and I have an Ultrasonic and decided to dip it in for a good clean up,and now the atv don’t want to start,it tried but it backfired a little bit but still won’t start,any suggestions?

 

 

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What do you mean a bit of a choke issue ?

Did you disassemble the carburetor? If not you may need to open the carb up and take it apart.  Ultrasonic cleaning will only go so far.  They loosen things up quite well but if the stuff that came loose  can’t get out of the carburetor then it’s useless.  

I would open the float bowl and blow the crap out of it.   Blow into where the fuel line connects and raise the float up and down while you doing this to make sure air is coming through and into the carb. 

Blow out all the jets etc, that should clear things up, by chance did you mess around with the air fuel screw ? 

 

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What do you mean a bit of a choke issue ?
Did you disassemble the carburetor? If not you may need to open the carb up and take it apart.  Ultrasonic cleaning will only go so far.  They loosen things up quite well but if the stuff that came loose  can’t get out of the carburetor then it’s useless.  
I would open the float bowl and blow the crap out of it.   Blow into where the fuel line connects and raise the float up and down while you doing this to make sure air is coming through and into the carb. 
Blow out all the jets etc, that should clear things up, by chance did you mess around with the air fuel screw ? 
 

Yes I did take I took apart the entire carburetor and after the ultrasonic I sprayed carburetor cleaner and blew out each jet,I did take out the A/F mixture screw so I could properly dip in the carb on the ultrasonic,I just have to get the specs for how many turns out do I need for that screw,a Bit of choke I meant I normally choked the atv and it would start,but since I cleaned up the carb it won’t start,I did notice the gasoline had water and it was more yellowish than normal so I drained that and I will buy 91 octane or Ethanol Free gasoline I had regular gasoline on it,which the manual says that 91 octane is better,I’m pretty good at cleaning carbs,just asked if anyone thinks is either gasoline issues or a/f mixture screw,I did take apart the carb yesterday again but did not have time to install it on the atv,other stuff came up.


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Ok now I understand.  Well I would assume it would not fire because of the water in the fuel.   I would set the air fuel mixture screw at 1-3/4 just to get the engine fired up and adjust from there.  If your not familiar with the final adjusting let me know and I will explain.  It’s pretty simple. But this all hinges on if the bike fires up.  My guess is once you change the fuel you should be good to go if  carb is clean like you said.  Double check for spark as good practice and make sure your plug is not fouled and give it a shot.   

If spark is good and the bike still does not fire up then hit it with a little starting fluid into the air intake. If she tries to fire up then there’s obviously a fuel delivery issue. 

 

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Ok now I understand.  Well I would assume it would not fire because of the water in the fuel.   I would set the air fuel mixture screw at 1-3/4 just to get the engine fired up and adjust from there.  If your not familiar with the final adjusting let me know and I will explain.  It’s pretty simple. But this all hinges on if the bike fires up.  My guess is once you change the fuel you should be good to go if  carb is clean like you said.  Double check for spark as good practice and make sure your plug is not fouled and give it a shot.   
If spark is good and the bike still does not fire up then hit it with a little starting fluid into the air intake. If she tries to fire up then there’s obviously a fuel delivery issue. 
 

IMG_0196.JPG
read the statement on the picture I attached I’m using an iPhone and I’m not very familiar with it yet,but that’s the reply to your last conversation.


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Ok well that’s a great post Lisa 43 and single! 😂 just kidding. 

All I’ve ever used with Quadcrazy is my iPhone it’s easier for me.  Any additional information you have in the Kymco can be posted right here. If it’s a downloadable manual then maybe @Admin can explain how it’s vetted for any malware and put on the Quadcrazy platform library.  Its very much appreciated since there are quite a lot of members that have these machines. 

As far  as a valve adjustment that should be pretty standard as any other machine and most likely long over due.  Did you happen to do a compression test ?

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Ok well that’s a great post Lisa 43 and single! just kidding. 
All I’ve ever used with Quadcrazy is my iPhone it’s easier for me.  Any additional information you have in the Kymco can be posted right here. If it’s a downloadable manual then maybe @Admin can explain how it’s vetted for any malware and put on the Quadcrazy platform library.  Its very much appreciated since there are quite a lot of members that have these machines. 
As far  as a valve adjustment that should be pretty standard as any other machine and most likely long over due.  Did you happen to do a compression test ?

No I haven’t but I do have the kit for that and I will try and get it done today after work


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@orvilleortiz538 looks like you are using Tapatalk, which runs on their app connected to our forum. You can also just use a browser on your phone and access this site with more features. With Tapatalk, you really only have access to the forums. 

All files in our downloads section added by members go through an approval process where we check the files. This is in the downloads section. URLs and files posted in our forums do not go through approvals and we sometimes don’t see them unless someone reports a post.

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3 hours ago, Frank Angerano said:

Ok now I understand.  Well I would assume it would not fire because of the water in the fuel.   I would set the air fuel mixture screw at 1-3/4 just to get the engine fired up and adjust from there.  If your not familiar with the final adjusting let me know and I will explain.  It’s pretty simple. But this all hinges on if the bike fires up.  My guess is once you change the fuel you should be good to go if  carb is clean like you said.  Double check for spark as good practice and make sure your plug is not fouled and give it a shot.   

If spark is good and the bike still does not fire up then hit it with a little starting fluid into the air intake. If she tries to fire up then there’s obviously a fuel delivery issue. 

 

Yeah,I’m very familiar with the A/F Mixture screw,I buy this atvs to fix and flip and it works out pretty good,anyhow I did check the spark,maked sure battery is fully operational,and if this persists then I think I may have to dig a little deeper and do Valve adjustment,I don’t know if anyone even attempted such thing on this atv,it’s an 07 Kymco Mongoose 300cc  so it’s been what 12 years? I bought it and it was sitting outside on the Florida weather and as you may know this ATV’s don’t do well outside because they rust away very quickly,I have some wiring diagrams I dug up doing an extensive search for the Rapidity and found some interesting stuff where would I post such info for other fellow riders,thanks for your help Frank!!!

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55 minutes ago, Admin said:

@orvilleortiz538 looks like you are using Tapatalk, which runs on their app connected to our forum. You can also just use a browser on your phone and access this site with more features. With Tapatalk, you really only have access to the forums. 

All files in our downloads section added by members go through an approval process where we check the files. This is in the downloads section. URLs and files posted in our forums do not go through approvals and we sometimes don’t see them unless someone reports a post.

Ok I did acces the forum now not using Tapatalk,I was just letting Frank know that I found some Images of 250cc water cooled engines wiring diagrams and just wanted to know where would I share this images so anyone looking to wire up a 250cc water cooled engine can have access to a wiring diagram because I know how frustrating it is no knowing what is what,having a harness looking like a spaghetti bowl!!! This diagrams have Fan wiring hook up and diodes etc,I did an extensive search because I bought a 07 250cc Rapidity atv and the owner trashed the original harness and bought one of (VMC Chinese parts) I’m not trying to sponsor anything or advertise,but they sold him a harness for a 250cc air cooled engine and the harness was way off,it had a/c cdi instead of D/C,but any way is some images that might help others because I spent days literally on my phone and laptop looking for info and this was the closest I got,I have a harness coming today and fingers crossed it matches the original because this is coming from UK UD-Spareparts.com has a lot of Chinese wiring harnesses that Amazon and EBay don’t have.  @Admin thanks for such an awesome forum!!! Hopefully I can contribute to alot of our Quadcrazy brothers and sisters....

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That’s some good stuff. I would def like to see them diagrams. Post a few pics if you can. 

We just had a member that needed a diagram for the water cooled rapidity.   

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