IM having problems with my 03 250. I took the carb apart to check the float level and jetting because it was running rich and fuel was coming out the overflow tubes when i kick it. Float level was perfect, if i measured it correctly, slow jet was partially plugged so i cleaned it out. I put it all back together and kicked the hell out of it, it wont start and kicking it like i was made fuel come out the overflow still. I pulled the plug and it was wet so i checked for spark, plenty of spark. I know it takes 4 things to make a bang; fuel, air, spark and compression. The compression is great, its a new top end, like i said, there is plenty of spark, the plug is wet so i know im getting fuel and there should be no reason its not getting air. The filter is clean. What am i missing?
Im stumped, please chime in.
- Thread starter Maverik
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Ok, that certainly makes sense. Are you familiar with the carbs on these bikes? Something struck me as rather odd with the float valve assembly. There is a needle that is pushed by the little lever on the float to shut the valve off, that much is normal, but the peice that the needle pushes up into moves out when i drop the floats, and pushes back in to a point where the needle starts pushing into it. Is this normal? I would think that the valve should stay put and the needle would be the only thing moving in and out.
The way the floats work is as the fuel level goes up floats go up. the floats have the little metal tab that pushes the needle up into the seat closing of the fuel to the bowl. If some thing is wrong with any part of the mechanism it will either not let the bowl fill up or always over fill the bowl running fuel out the over fill tubes on the carb and into the cylinder.
What it sounds like you are saying is that you said tha metal tab is moving enough that the needle is not seating and letting fuel by.
I would check thr float measurement (probably in your owners manual and bent the floats to match that measurement.) Take the floats out so you can look at the needle and seat.(look for junk in the seat or a severe ring on the rubber tip of the needle)
Check to see if every thing is attached correctly and moves freely.
Hope this is not too much info and it helps :cool:
What it sounds like you are saying is that you said tha metal tab is moving enough that the needle is not seating and letting fuel by.
I would check thr float measurement (probably in your owners manual and bent the floats to match that measurement.) Take the floats out so you can look at the needle and seat.(look for junk in the seat or a severe ring on the rubber tip of the needle)
Check to see if every thing is attached correctly and moves freely.
Hope this is not too much info and it helps :cool:
- Jul 16, 2004
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When you pull the carb apart again, spray carb cleaner in every little hole in there and through the lines this way you can make sure you get everything out and there is nothing clogged in any of the lines.
- Thread starter
- #7
I took it apart again and rechecked the float assembly. I checked the float height it was 6.0mm. 6.5 +or- 1mm is normal according to the manual. I also tested the valve seat by blowing into the fuel line, i couldnt blow into it when it was seated, so its seating properly, right? Is there anything else you can think of that i should check before putting it all back together again? I didnt change anything so i know i didnt fix anything. Is there any reason it wouldnt be getting enough air if the filter is cleaned and the air screw is turned 1.5- 2 turns out?
sick 96 250, i had already cleaned everything with carb cleaner the last time i had it off, which was about an hour before my original post. I will do it again though now that its apart again, just to be sure. Thanks.
sick 96 250, i had already cleaned everything with carb cleaner the last time i had it off, which was about an hour before my original post. I will do it again though now that its apart again, just to be sure. Thanks.
- Thread starter
- #9
Its hadr to measure accuratly, but i did it like 5 times, and came up with 6.0mm. Thats within the range they mentioned is factory spec. Im assuming you mean i should go up to 6.5 or 7.0mm? Wouldnt that actually alow more fuel into the bowl by closing the valve later? Or do i have it backwards?
Its hard to go by the directions they give in the manual to measure float height, they tried to show it, but it just isnt clear enough or Im to dense to understand it. The tab on the float assembly is almost touching the needle on the valve as it is because of that clip they have holding it on the little tab.
Its hard to go by the directions they give in the manual to measure float height, they tried to show it, but it just isnt clear enough or Im to dense to understand it. The tab on the float assembly is almost touching the needle on the valve as it is because of that clip they have holding it on the little tab.
Hmm, interesting. Tis only spits out fuel when it is bouncing around. Is the pivot pin to the floats ok?
Try putting the bowl back on and hooking up the fuel line and turn the gas on and bounce the carb without putting the carb in the bike.
Maybe That will help you figure out what passage in the carb is responsible for the over fill. and you can narrow down possibilities.
I hope I am helping and not running you around.
Try putting the bowl back on and hooking up the fuel line and turn the gas on and bounce the carb without putting the carb in the bike.
Maybe That will help you figure out what passage in the carb is responsible for the over fill. and you can narrow down possibilities.
I hope I am helping and not running you around.
- Jul 16, 2004
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Shouldnt most floats be set to 16mm and not 6mm? I havent looked at my specs in a while but I just remember it was higher that 6mm for the float height? But I could be wrong
