carb not taking gas

[gurt]

Hi everybody,
I'm having trouble with my 1976 yz 125. Im running a 34mm mikuni round slide that just doesnt seem to be working correctly. Whenever I turn the gas on, the carb doesn't want to take any in. Instead, it just barely trickles down the line (and I mean barely). I checked the lines, and gas pours out when it isn't connected to the carb, so thats not the problem. I cleaned out all of the breathers and ran wire through them, so I know that the are clear. The only way the lines fill up is if I really rev the bike up so the gas gets sucked down, and even then it isn't enough. Any ideas on what the problem is?

 

[IndyMX]

Take the petcock off the bottom of the tank, and make sure that the screen on it is clean..

Also check to make sure your gas cap is clean, and that the breather on it is clear.

 

[ZOMBIE666]

have you checked the carb float and needle valve? sounds like it could use a cleaning

 

[gurt]

Yea, I checked all of that. I know it isn't the tank or petcock because when I disconnect the line from the carb, gas just pours out. I cleaned out the needle valve and made sure the floats werent getting hung up on anything too. The thing that is driving me crazy is that it wasn't doing this a week ago.

 

[2strokerfun]

Take the carb apart again and clean it well.

 

[gurt]

I took it all apart and let it soak in a solvent tank, but it is still screwed up. I think I will just end up buying a new needle valve and seat, to see what happens.

 

[Beuford]

Is your carb empty?
If you are judging the flow by a inline filter then it will show only a trickle and will fill up as you rev it.
My 06 does this and runs fine.
None the less, your float level may be off and could be giving you problems.

 

[whenfoxforks-ruled]

The seat and float valve should be replaced. Make sure the passage is clear. Blow cleaner through all the vent connections. Make sure the floats are installed correctly. You do have the floats below the brass tang?

 

[2strokerfun]

And if you don't have an air compressor, go buy a can of that computer cleaner air to help you clean the carb after you take it apart and soak the parts. If there is gunk in your carb, you have to get it out.

 

[gurt]

I bent the tang to the extreme, and that turned out to be it. At first, gas came out of the overflow so I took it apart and did a little less. works fine now. Thanks for all the input guys.