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Can't Solve Carb Flooding

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2003 XR250R with air box mod and baffle removed.  135 main and 48 pilot at sea level.  I'm a self taught and very novice mechanic...

After a hard crash, I had problems hot starting and began to investigate possible carb flooding.  I have never adjusted the float level and began to limp my way through setting the level by watching videos, reading service manual, etc.  After a total clean of the carb to include new float and float valve, I am still leaking fuel from the overflow tube when turning the fuel on.  I am setting the level with the carb on it's right side, float valve seated and tang barely touching the top of the valve.

I am wondering if I am reading the float tool correctly as silly as it sounds.  It's the Pit Posse pictured below, the same one shown in the XR service manual which calls for the height to be 12.5 mm. The photo in the manual shows this setting as well but i'm at my wits end as to why it continues to flood once I turn the fuel on.

Any help would be greatly appreciated.

 

 

20170807_101959.jpg

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Omg i had the exact fault drove me mad ,full carb kit adjusted to 12.5mm overflowing no joy was the float side to side play on the pin had to tweek it so held tightly . Also i set it to 13mm directly inline

with the main jet and the drop 5 mm more so total drop of 18mm

hope this helps 

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6 hours ago, Romney1 said:

Omg i had the exact fault drove me mad ,full carb kit adjusted to 12.5mm overflowing no joy was the float side to side play on the pin had to tweek it so held tightly . Also i set it to 13mm directly inline

with the main jet and the drop 5 mm more so total drop of 18mm

hope this helps 

Can you explain why the discrepancy between what the service manual says and what you found worked for you?  Is this standard for the XR?  

Thank you

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is the needle and seat doing its job shutting the fuel off ?

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7 minutes ago, S.O.A.N.Z said:

is the needle and seat doing its job shutting the fuel off ?

I would sure hope so, I just replaced both needle valve and float.  Not sure though....

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Use a flashlight to look down in the needle valve bore and look at the seat and walls of the bore. Make sure they show no signs of corrosion. You can use a Q-Tip with a polishing or rubbing compound to clean the seat.

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Well I tested all the shut off valve on mine plus they where brand new . I left

the bole off and manually operated the float to make sure it was shutting the the fuel off . 

Also placed the float in fuel to make sure it wasnt taking any fuel in and holding it open .

i set and set the float fo 12.5mm and it overflowed everytime the Xr400 have a drop of 14mm or around that so i was running out of options so set mine to 13mm and its operated perfectly since then ino it different from the manual but worked for me but do check that the float has no side

to side play and just tweek the bracket to get it slightly tighter.

 

aslo i found that the pin that shuts the fuel off the sping wire can get stuck and hold the float down i made sure it was the way round so it say under the hinge side . 

That should make sense while looking at your carb 

 

cheers 

 

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Falling will allow fuel in every port of the carb. After falling the best way to restart is to turn off fuel. Hold throttle wide open and kick the bike normally until it starts. Once it starts turn the fuel back on.

Getting the internal ports of the carb clear off fuel by turning off the fuel and holding the throttle open works just about every time.

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31 minutes ago, 4strokeridertt said:

Falling will allow fuel in every port of the carb. After falling the best way to restart is to turn off fuel. Hold throttle wide open and kick the bike normally until it starts. Once it starts turn the fuel back on.

Getting the internal ports of the carb clear off fuel by turning off the fuel and holding the throttle open works just about every time.

I appreciate the feedback.  This problem has persisted since the crash and only happened when the bike was warm.  Cold start was easy, two kicks and it would fire up.  After hitting the kill switch the bike refused to start.  This started the  process of cleaning the carb, setting the bowl height, and now the perpetual drain from the carb overflow tube...LOL.

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To put on a bow on this thread my issue was the float bowl level.  I had it set to the service manual specs of 12.5 mm but like @Romney1 recommended, it was way too low.  Also, as@Trailryder42recommended, with the new float valve, a good polish of the port was needed as well.

Thanks all for the help. 

Edited by Rodeojones
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On Monday, August 07, 2017 at 9:38 PM, Trailryder42 said:

Use a flashlight to look down in the needle valve bore and look at the seat and walls of the bore. Make sure they show no signs of corrosion. You can use a Q-Tip with a polishing or rubbing compound to clean the seat.

Exactly where I would start right after new rubbers.  A qtip and lapping compound.

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