BBP250
New member
I got a et250 for my kid to ride and Im having trouble with the carb. It has a keihin with the site tube on the side. originally it was running fine, it started kinda hard and had alittle bit of a bog but always ran ok. It got warm one day (about 45) and I let him ride in the yard and it lost power, wouldnt move. So I took the carb off and cleaned it and checked all the gaskets etc. put back together, now it keeps flooding out. I have adjusted the bolt on fuel pump on the bottom of the carb all the way out and all the way in, and still floods. kinda of at a loss,as I dont know alot about these carbs and have no manual. any help would be great! thanks!
They can be a pain to adjust. Make sure you got everthing back in place on the inside, and try starting with the fuel level adjustment screw at 6 full turns in. Be sure to lock it doen with the locknut every time you adjust it. They have a habit of falling out. Also the pilot screw can be opened up to get rid of the bog. They never were overly snappy (1 lunger) but they did pull fairly well (low gearing).
There are some posts on this in the last 3 months.
I also suspect that your pilot circuit may have gotten clogged, or some water freed up (ice melted).
There are some posts on this in the last 3 months.
I also suspect that your pilot circuit may have gotten clogged, or some water freed up (ice melted).
BBP250
New member
Thanks for your reply! Ya, I thought I might have to take it back apart! Can you run these without the aircleaner boot? I started it without the boot on and thought I had the fuel level adjusted, but after putting the boot back on (what a pain in the ***!)it started the flooding. Also there is a small hole next to the adjuster bolt on the bottom is that supposed to be there?Thanks again!
I have run several of these sleds without the airbox. That hole is a vent for the pump diapraghm. If it is leaking gas, then you have a leaking diaphragm.
BBP250
New member
OK thanks again! I have currently taken it back apart and cleaned it, just haven't put it back on. I think I might try to run it without the boot. This sounds stupid but when I had it apart last time I found that hole and sylconed it, maybe thats why it would adjust right!!!
BBP250
New member
also, the main jet, is that supposed to be bottomed out or screwed out 1 turn(It has the alum. screw over it)
Do you have a pic of what you are calling the main jet? The carb for the ET250 should not have a main adjustment screw, but should be plugged off.
Yah, that hole on the bottom is the vent for the diapraghm. With that plugged, the diapraghm cannot move freely with the pulses from the crankcase.
Yah, that hole on the bottom is the vent for the diapraghm. With that plugged, the diapraghm cannot move freely with the pulses from the crankcase.
BBP250
New member
Yes it is plugged off with the alum. cap screw. I was just reading some other post from slast. He talked about a needle being adjusted to 3/4 of turn and you suggested 1 turn. The only adjustment I thought was the air screw which is 2 turns. He also refers to this as the mainjet, so I was confused. Is the Main jet supposed to be bottomed out before you put the cap screw back on?
Yes on the MJ
BBP250
New member
thanks ding you have been a huge help, this is my first time on this forum and you saved me from alot of guess work.Thanks again!!!