# Kymco Cobra Cross (Top Boy) 50cc no start



## Mike2daE (Apr 18, 2018)

Hello everyone!!! Newby to the forum here... Not sure if I posted this in the right place, but here it goes... I have a Kymco Cobra Cross (Top Boy) 50cc, Oil injected, Reed Valve Engine Scooter (not 100% sure of the year, somewhere between 2000 & 2004 I believe) & I'm having some issues... The scoot was running fine till 2wks ago at which time, I parked it when I got home form work & when I went to leave the next day it wouldn't start for nothing!!! It turned out that it needed a good carb cleaning due to both jets being plugged, so I did that & it fired up perfectly & ran great for the next 2wks... My wife rode it to her work yesterday & said it felt like it was going to die when coming to a stop, then after work it would only crank, but wouldn't start at all... I went up to her work assuming it was doing the same thing it's been doing all winter long, which was giving me hell to start it after it set out in the cold for a while... Normally I just cover the air intake with my hand until it starts, then let go & play with the throttle until it revs up & off I go, but this time it didn't work... I got it to catch a couple of times for about half a second while "manually choking" it like this & got it to catch a couple of times & rev once or twice by holding wide open throttle while starting, then playing with the throttle once started, but that was it... Got it home & inside to warm up & tried it again, but nothing... Let it sit overnight & tried again this morning & nothing... I pulled & cleaned the carb twice today & still nothing (although the pilot jet was clogged again the 1st time, but the 2nd time everything was clear)... It's getting good spark & the plug is good, it's getting plenty of air flow & the filter is good, the carb is squeaky clean, if I pull the plug & stick my finger against the hole while starting, I can feel good compression & my finger gets wet with fuel, so I know fuel is getting to the combustion chamber & if I put my hand against the air intake side of carb, it sucks it in pretty good & fuel starts coming out of the intake side of the carb... The only other thing I knew to try was a valve adjustment, but this is a reed valve engine, so that's not exactly something that can be done, but I did take the reed valve out & inspect it... I found that the actual reeds (plastic flaps) were worn into the open position & had pretty big gaps, so I turned the reeds around & it sealed up pretty much completely, other than a very minuscule & almost non existent piece of a sliver of light... I put it all back together & nothing changed, I even played with air fuel mix & idle a little bit, but nothing changed so I put them back where they were... I even tried spraying starting fluid directly into the intake side if the carb, but nothing... I just squirted gas into the spark plug hole & nothing... I have no idea where to go from here & this is my only means of transportation, so it's very important that I get this figured out as quickly as humanly possible... Any & all help will be greatly appreciated I assure you... Thank you in advance for your assistance.


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## finaprint (Jan 29, 2006)

Finger getting wet with fuel checking compression means utterly fouled out, the engine will not start like that. Baby 2 strokes foul out super easy.


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