mantas1992 Posted April 12, 2014 Share Posted April 12, 2014 I have recently joined this forum , to get some knowledge and advise from Yamaha lovers. I have 50cc Yamaha neos scooter, it not powerful enough as i need to travel to work on A roads which speed limit is minimum 40 mph. So i have purchased non runner Yamaha YBR 125 which been standing for two years. I have experience fixing bikes with carb, but I never had something with fuel injection system. After I got it in my yard I have took it apart cleaned tank, all hoses, filter, fuel injector,changed oil and it didnt start so I started narrowing down the problem, it creates the spark so I have looked in fuel feeding and noticed there is no fuel coming from tank to ejector. I took out fuel pump and connected to power and tried to start bike and once I turned ignition on it makes click noise and once I trying to star its not doing anything and gets a bit hot, can it be blocked? also I put some fuel inside fuel line from tank to injector and tried to start it just to see if fuel injector will work, but its not taking fuel in is that because the pump generates pressure or it could be blocked to? Thank you Link to comment Share on other sites More sharing options...
blackhat250 Posted April 12, 2014 Share Posted April 12, 2014 Hi Mantas " You"l be praying for a quick fix " ... the pump needs to pressure , it will be goosed. did it run before you stripped it,, Link to comment Share on other sites More sharing options...
mantas1992 Posted April 14, 2014 Author Share Posted April 14, 2014 No it haven't, of course if I squirt some petrol on piston it tries to start. So fuel pump then is most likely seized, should I get new one and new injector ? as is fuel pump is clogged up I suppose the injector will be the same Link to comment Share on other sites More sharing options...
dt502001 Posted April 14, 2014 Share Posted April 14, 2014 Most likely the injector will be fine,the bike wont run unless it has the 30-60 psi(not sure what the specs are for a ybr125) of fuel pressure from the pump. You can soak the injector in cleaner if it looks dirty just be sure to remove the outer seals first.There is f all to a injector ,a needle, a coil,seals and a nozzel and they rarley plug up to the point the bike wont run.Most injectors on gas engines will go 600k and never fail Link to comment Share on other sites More sharing options...
wild foamy Posted April 14, 2014 Share Posted April 14, 2014 As above, if the pump isnt pressurising the fuel gallery to the injector, the injector will do sweet f*all Link to comment Share on other sites More sharing options...
Moderator Airhead Posted April 14, 2014 Moderator Share Posted April 14, 2014 from what i've read over the years on here...the fuel pump is the biggest let down with this bike. Dont know if it can be fixed or whether you can strip and clean it but it's goosed anyway so theres no harm trying? Link to comment Share on other sites More sharing options...
wild foamy Posted April 14, 2014 Share Posted April 14, 2014 There are replacement in-tank pumps available HERE Link to comment Share on other sites More sharing options...
dt502001 Posted April 15, 2014 Share Posted April 15, 2014 After following Foams link I kept going to the home page that fuel pump is used in somany bikes and scooters it shouldn't be hard to find one or a injector used,thoe for 30 bucks would be silly to not put in a new one. Also a good way to find out the working pressure/flow rate of a fuel pump for different bikes yours is 3 bar (45 psi)opereating and a working pressure of 4.5-6 (65-80psi max) bar with a flow rate of 35lph. or aprox 1/2 a liter per min .All usless information if you dont have a fuel pressure gauge but good for me. After you install your new pump,if the bike still dosen't run you will need to check the circut to the injector for a pulse.To do this it best to use a noid light any noid light will work but try to find one with the same pin connection as the harness has then you dont have to make jumper wires to connect it. Here is a whol lot to choose fromhttp://www.calibex.com/Noid-Light-Tester/search-html?nxtg=25940a50051a-410904226C860CFC Link to comment Share on other sites More sharing options...
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