JCL-250 starting & running issue By hotdogman (Read 746 times)

[hotdogman]

Ok, this could be long, have patience. 2007 JCL-250, 289 miles on it. It has been sitting since 2013 because of a no start issue. I get it home, take it apart and replace fuse by starter solenoid, BAM, we have power with the key to everything(battery is bad so using a jump box). Turn it over but no gas to carb, check for fuel in tank, nothing, fill it up, still very little fuel to carb, check all vaccum lines, fuel lines, no cracks or leaks, will start with starting fluid but stops when gone. Pull vaccum line at pump, have a lot of vaccum, connect it back and pull fuel line it is pumping a lot of fuel all the way to back of exhaust as it pulses. hook lines back up and disconnect at carb and it is pulsing good here now but still wont start after hooking line back up.(it will with starting fluid). Pull carb, disassemble and clean, looks pretty good but the main jet was a little dirty and the pilot jet was plugged. cleaned and reassemble. still only starts with starting fluid or at half throttle. When it does start at half throttle without starting fluid it will run but will not idle, pull carb back off and check everything, all looks good, screw is set at 2 1/2 turns out, I adjust the idle screw to max and it will idle at about 600 then die but it will start right back up  and run if I hold throttle half way or more. I am still getting a good pulse of fuel from pump, no vaccum leaks or fuel leaks have been found. I know this is probably in a thread somewhere but I have not found it yet, any help would be greatly appreciated. Low mileage scooter looking to put a lot of miles on. Feeling lost without a ride. hmmmm, wish I had my Harley back, lol

[darrell]

sounds like the idle passage is still plugged a little. when I tore my carb apart and cleaned it up real good the kit I bought gave me a 35 idle jet and a 105 main jet. the idle jet was a 35 and the main was 110 originally but the air mix screw was turned all the way in. I installed the 105 and back out the air mix screw only 3/4 a turn. when I rev it up and let go of the throttle I can here a little back fire going on. when I ripped apart the engine to rebuild it, I thought it had a little to much carbon build up on the head and piston. my next step is to buy a 108 main jet and back the air mix screw out another 1/2 turn.

[hotdogman]

Thanks Darrell, I will be trying to work  on it a little more tomorrow or at least this weekend, I will be pulling the carb back off and making sure I didn't miss something and double check all passages. I hear people talking about fuel pumps being a major problem on these units but this one appears to be pumping good up to the carb.

[darrell]

I like to use the clear fuel lines and place the filter after the pump and before the carb. it's easier to see debris flowing. and it's normal to use a whole can of carb spray cleaner and compressed air when a scooters been sitting for years. lol I have read stories where the air mix screw likes to vibrate out so when I get mine dialed in to where I like it, I will apply some rtv and tape to prevent the loss.

[hotdogman]

I have some yellow Tygon fuel line i will use and may move the filter.