07 450 gas leaks out of carb overflow


7 replies to this topic
  • warrior86

Posted January 31, 2007 - 10:45 AM

#1

well i just got done putting my bike back together. I had a lot of it apart so i could clean it, grease it, and adjust the rear shock. Adjusting the rear shock did require me to take the airbox boot off the carb, but other than that, the carburetor was NOT touched.

So i got everything back together and go to kick it over after sitting for about a month. Turn the fuel ON and about two seconds later i hear liquid dropping to the ground...its gas. I turn the fuel off and the gas stops.
Ok, i think to myself "maybe the bowl is full" because while i had the carb visible, i twisted the throttle several times in fascination of "the squirt"...which eventually led to all the "squirted" fuel being dumped out of an overflow. Atleast thats what i figured because the flow of fuel stopped after a couple of seconds without me interfering.

I dont see how dirt could have gotten into the carb because i had the orifice covered the whole time. Bike ran perfect before i tore it down.

Also, i said what the heck, let me atleast get it started. So i kicked it with the fuel off. Started right up and its about 30 degrees out. I rode it up and down the block with the fuel off and it ran great and idled fine. Tried turning the fuel on again and a second later i had a puddle of fuel under my bike.

Any ideas? I love this bike but the bs is starting to get to me.:ride:

  • Reyndogg

Posted January 31, 2007 - 10:56 AM

#2

sounds like your float drain bolt is loose...

  • warrior86

Posted January 31, 2007 - 11:28 AM

#3

nah, float drain bolt was fine. I tapped the bowl about 20 times with a 1/4 inch ratchet and then "see-saw" the bike on the stand to get it to bounch around. Slowly turned the petcock on and crossed my fingers and wow...good luck. Everything seems to be good now. Thanks for the quick response reyndogg. :ride: :ride:

  • grayracer513

Posted January 31, 2007 - 11:39 AM

#4

A simple matter of a bit of dirt on the float needle. It's a common occurrence with any type of motorcycle. Quite often, the cure can be nothing more than just riding it, but sometimes it's helpful to run it with the gas off for a ways to lower the float level, then open it back up. The flood of gas rushing in to refill the bowl is stronger that way, and more likely to wash a piece of dirt off the needle seat.

It's just a little thing. They all do it. Chill.

FYI, the accelerator pump squirt comes from the float bowl, and is delivered to the throat of the carb and down the intake port. It doesn't cause float bowl overflow.

This whole thing is one more problem that will vanish when EFI gets here, too, BTW.

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  • warrior86

Posted January 31, 2007 - 12:14 PM

#5

Thanks gray. Dont worry, this isnt another "my 07 reliability sucks" thread. To be honest i was just alarmed. I know that in general, dirt gets in, but i wasnt going to rule that as a possibility because the bike has 13 hours on it, im using a twin air filter, AND i have a filter skin over that...plus i havent been riding in dusty conditions.

I guess from sitting for a month the gas began to turn to laquer or w/e they say happens to gas after a while.

btw, as stated earlier, i tried running the bowl out of gas then turning it on so that the fuel would have a blasting effects but no go. Luckily, tapping it knocked it loose.

and yes, efi will cure a lot of these problems, but i think it will bring a new set of different problems. Atleast initially. Thats actually why i was determined to get an 07, being that it was probably the last year for carbs. I didnt wanna purchase a first or even second year efi.

Let me tell you tho, its nice to get back on this bike!!!:ride:

  • warrior86

Posted January 31, 2007 - 12:16 PM

#6

btw, as far as the squirt goes, it didnt drain from the bowl overflow but rather "a" overflow. Theres several of them and i have no clue which is was, i just remember the sound of gas pissing onto my garage floor.

  • grayracer513

Posted January 31, 2007 - 12:59 PM

#7

btw, as far as the squirt goes, it didnt drain from the bowl overflow but rather "a" overflow. Theres several of them and i have no clue which is was, i just remember the sound of gas pissing onto my garage floor.

There should be 5. One comes from the bottom of the float bowl, and serves two purposes; one as a bowl drain, and one as an float level limiting overflow. It's connected to a standpipe in the bowl which is open at the top, and stands a little above the normal bowl level, but lower than the top of the needle jet/discharge nozzle. The idea is that if the float needle doesn't seal completely, the fuel can't get any higher than the top of the pipe without running out. The passage leading from this pipe out to the hose is T'd into a drain passage that you open with the small screw at the base of this hose. This hose is the most likely place a flooding carb would leak from.

The rest are float bowl vents. Typically, there are two ports that come straight up out of the roof of the float chamber. There is a T fitting in each of these to which two hoses are attached, one going down the side the port is on, and a second going up over the carb and down the other side. The use of 4 separate hoses is for redundancy and to break any vacuum in the case that one hose should pickup any water.

  • YZ426F Rider

Posted January 31, 2007 - 01:23 PM

#8

It's just a little thing. They all do it. Chill.

Of all the great technical info I've read from Gray this is by far my favorite.

This whole thing is one more problem that will vanish when EFI gets here, too, BTW.

Yeah, can't wait for that! Although, just today I discovered that I have to replace the injector control manifold thing on my pickup :ride: I was just getting ready to sell the dang thing and get a new one...





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