New Jonwa won`t start By danso (Read 3,183 times)

[danso]

Bought the Scooter about a month ago. Ran fine for 2 weeks the started getting hard to start. I noticed when running it wasn`t as good as before. Kept geting worse and eventually quit starting altogether.
I have come to you seeking help on the advice of someone who recomended you.
Here`s what I`ve done so far. Bought and installed a new carb.New Plug and made sure it was gaped correct. Oh by the way this is a 139 qmb 4 stroker. ok still no start. Learned how to check the valves and did an adjustment. They were almost closed. I set them for .OO4. Put it all back together and still no start. I am frustrated as i need this scooter for transportation. Awaiting your advice if any is out there. thank You.

[alleyoop]

First make sure the KILLSWITCH is on the RUN POSITION, that is on the Right Hand Grip usually it is RED on top above the Start Button. Have you checked for SPARK?
Take the BOOT CAP OFF the plug on the motor and stick the old plug in and HOLD THE SPARK PLUG metal part on the VALVE COVER or MOTOR and crank it and see if the Spark Plug is FIREING. IF IT IS SPARKING THEN WE GO TO THE NEXT STEP- FUEL DELIVERY CHECKS:

CHECK FUEL DELIVERY:

Take the Carb Fuel hose off the Carb put it in a container and crank the motor over.

A. IF FUEL STREAMS OUT, fuel to the carb is good, Filter is not clogged and Petcock is working now

Re-connect the Fuel hose back onto the carb—GO TO CHECK CARB.

B. NO FUEL COMES OUT, take the Fuel Filter off and crank it again

a. If fuel comes out the Fuel Filter is Clogged.

b. If fuel does not come out –GO TO CHECK PETCOCK.



CHECK PETCOCK:

Take the Vacuum Line OFF going to the Petcock from near the carb and suck on the VACUUM LINE.

A. If fuel comes out you have a VACUUM PROBLEM.

B. If fuel does not come out you either have a bad petcock or a clog from the tank to the petcock.

Disconnect the fuel line going to the Petcock from the tank.

a. If fuel comes out the petcock is bad

b. If fuel does not come out either the hose from the tank is clogged or the tank outlet is clogged.



CHECK CARB:

First turn the Fuel Ratio Screw Clockwise until it stops and then turn it out Counter Clockwise 2 ½ turns

And try to start it.

A. If it does not want to start get a paper cup and put in about teaspoon of gas. Take the Vacuum hose off the Intake Manifold squeeze the paper cup and make a point and pour the little bit of gas straight into the Vacuum hose and connect the hose back onto the intake manifold. Now try to start it.

a. If it attempts to start or start and die now we know gas is not being sucked out from the carb bowl

Let me know the results of the items above so we can get it running.
IT ALSO WOULD Be Good to take a picture of the Carb AREA on both sides so I can see if anything is wrong.
Alleyoop

[danso]

OK I`ve got spark. As for fuel delivery when i took the fuel hose off and turned it over it spurted a little gas out but didnot stream out so maybe thats the problem. Will check it out and podst back tommorrow. Thank You very much I am much releived.

[alleyoop]

Great, It is either Fuel Delivery Problem or you may have adjusted the Valves wrong.
Not a problem we will get it going. So next follow the steps so we can pinpoint the problem.
Also since you put on a new Carb the IDLE SPEED SCREW may not be set correctly and that ALONE will cause it not to start. If the Butterfly is closed it will not start Also if it is OPEN to much it will not want to start. So also try to open the throttle a little when cranking and see if it attempts to start.
Alleyoop

[danso]

where is the fuel ratio screw?

[danso]

I took the vacumn line off and sucked on it and i got fuel coming out of the hose going into the carb. So now i think i have a vacumn problem. Could you show me the schematics of the vacumn system because i took off some of the polution stuff off not thinking i was creating a problem It appears all my trouble is brought on by myself.

[alleyoop]

Ok so you took off emssions stuff off, DID YOU PLUG up the VACUUM LINES GOING TO THE EMISSION Canisters AT THE ORIG near the INTAKE MANIFOLD or "T" OR "Y" splitters?

Also any hoses that you took off connected to the AIR FILTER and or TUBE SHOULD BE PLUGGED UP as well.
Like I mention it would HELP A LOT of you took pictures of the CARB AREA and HOSES going and coming to see if you left something open and not plugged up.
Alleyoop
Your Carb is very similiar to this but SMALLER. Notice where the FUEL RATIO SCREW IS.

[danso]

My carb doesn`t have a scfrew where it shows one in your picture. I tried to take a video with this laptop but I don`t know how to post it here. I have a phone camera I might be able to take some pics of the motor and hoses and post them up here if i can figure it all out but I think i`ll have to wait until tomorrow when my kid can come over and help me. It sucks to be so computer illiterate but i`m doing good to have got this far. thanks again i will post more when i get it all figured out. in the meantime the scoot just sits.

[alleyoop]

BUMMER you have a PLUGGED FUEL RATIO SCREW. You can drill out the PLUG to get at the SCREW behind it. THEY do that per EPA requirements so the mixture cannot be changed. Or some just go and buy an AFTERMARKET carb which has the Screw available and not plugged.
Here is a VIDEO on how to take the PLUG OUT:


Well if you can get the pictures to your computer put them on the desktop or folder Then you can Use Pushapicture.

picturepush.com/host.php?image=10075950

Just click on UPLOAD ANOTHER PICTURE in blue and find your pictures then Go down to the SECOND SET of links PRINTABLE PICTURES and click on the URL that SAYS FORUM 1 it will turn BLUE then RIGHT CLICK and CLICK on COPY then come here and PASTE IT.
Alleyoop

[danso]

Sorry for the delay.when i checked carb i found thart it did indeed have a fuel ratio screw. turned it all the way in and back out 2 and a half no start, put about a teaspoon of gas in the vacuum hose and reconected it and tried again not even a sputter. S now thats what i know you needed and again sry for the delay.

[alleyoop]

I am here to help you I know this stuff backwards and forwards so you are not telling me something you did or did not do.

So it is time to show me some pictures of the Carb area and the area you took stuff off. I also want to see the SIDE WHERE THE FUEL RATIO SCREW IS. YOU MAY HAVE A SLIDER CARB which are different.


If you dribbled some gas straight into the intake and it did not fire or nothing I have to say you DO NOT HAVE SPARK. Did you hold the PLUG on the VALVE HEAD or the motor when you checked for spark? Because if you held it on the frame that does not mean squat it may fire on the frame but not on the motor. The Battery is grounded to the frame so if the electrical is ok it will fire on the frame. But if it has a bad ground to the motor it will not fire while in the motor.

SO WITH THAT ARE YOU SURE you tested for SPARK CORRECTLY. Reason I say you may not have is because if you have spark the Little bit of gas you poured directly into the intake would have created an explosion NO IFs OR BUTS ABOUT IT. Unless of course when you adjusted the valves it was NOT AT TDC(TOP DEAD CENTER).
Alleyoop

[danso]

rechecked everything and now i am getting no spark when checking on the manifold. i am sure i had spark before so i am confused as to why i don`t now. the ground wire is attached and doesnt appear damaged.

[alleyoop]

How about your KILLSWITCH is it on the RUN POSITION?
Did the scoot get dropped or anything, when was the last time it was running and did anything happen that the problem started to happen. Are you checking for spark on the PIPE MANIFOLD, that may not be a good enough ground, check for spark on the VALVE COVER or the MOTOR ITSELF.
Alleyoop

[danso]

I gave up trying to fix my scoot. I just don`t have the place to work on it or the tools. I took it to a shop that sells mopeds similar to mine and they said they would look at it. They put a running new moped with the same motor as mine next to it and checked everything. Mine has low compression and they think thats why it won`t run. They didn`t charge me a dime but suggested i take it elsewhere. The compression was 90 and they said it should be well over 100. I looked on the internet and found that was not necessarily the case, since it is hard to get an accurate reading with so small of an engine. So now i`m stuck with a new scoot that won`t run. Only rode it 250 miles. Any offers?

[alleyoop]

Sorry to hear that Danso, But really all you need are simple tools. A Socket Set and a Set of Screw Drivers that is all.

Most shops will NOT work on Chinese Scoots unless you bought if from them. So going to a shop that sells BRAND scoots like honda and yamaha they will not touch it.

If you would put up some pictures of the CARB that is on there and the hoses I can help you get it running.

I can run you through some simple Fuel Delivery tests to make sure the Carb is getting fuel as well if the motor is sucking in fuel.
Alleyoop