04 WR450 leaking gas

I just picked up a 04 WR450 today that has been sitting for a few years.. The carb is leaking gas out of the drain hose at the bottom of the bowl. The drain screw doesnt go in all the way.. Is it supposed to? its about an eighth of an inch from going all the way in.. any ideas as to why? If i shut the gas off, it wont leak, the second i turn the gas on it leaks like a sieve..

floats are stuck, you'll need to clean the carb and replace the pilot jet anyways.

floats are stuck, you'll need to clean the carb and replace the pilot jet anyways.

+1 Normal issue if it's sat for so long

did you remove the drain screw from all the way in? have you messed up the threads? just take off the float bowl and look you need to remove it to clean that carb anyways...

yes i have to clean the carbs i know. figured the float was stuck, just wasnt sure if the drain bolt was supposed to go all the way in. I did not mess up the threads, they are fine, took it all the way out yes. I will take it apart tomorrow and clean it up and try it. Thanks for the info guys!

Took it all apart and cleaned it.. It was gummed up pretty good. Put it all back together and it didnt do it, but i started it and let it idle for a bit and was messing around with the idle and it started leaking again, but it doesnt do it constantly now like it did before??

Set the float height per the manual and replace the float needle if it has sat for a while. The needle can look clean yet be screwed up from sitting in an undrained carb for a while. Also make sure the floats seem to be in good shape and actually still float. Probably fine, but while your in there..... :thumbsup:

My 426 did the same thing. I replaced the needle valve assembly and the problem went away. There is a rubber O-ring that dries up and causes the leak. Check your manual and pull yor carb apart and I'm sure you will find your problem.

FYI my bike required part # 5BE-14107-00-00, but it looks like your carb is a little different acoording to the online parts fisch.

listen to dust dog

He knows the answer

My 426 did the same thing. I replaced the needle valve assembly and the problem went away. There is a rubber O-ring that dries up and causes the leak. Check your manual and pull yor carb apart and I'm sure you will find your problem.

FYI my bike required part # 5BE-14107-00-00, but it looks like your carb is a little different acoording to the online parts fisch.

There are a couple of things that could be causing the fuel leaks. 1) Debris is stuck in the needle valve. 2) The needle valve assembly is bad and not sealing properly. Instead of replacing the the whole needle valve assembly, I bought an o-ring for less than $1 and replace just the o-ring. If after replacement of the needle valve assembly and you still have problems, make sure to back flush the fuel line to get rid of all junk and retry again. This is a common problem when storing a bike and forgetting to drain out the fuel in the carb. Always drain the gas from the carb before storing the bike and you'll not have this problem.

It seems to have gone away. Hasnt leaked since. thanks for the help guys! Now i just gotta time the accelerator pump to get rid of the horrible bog!

It seems to have gone away. Hasnt leaked since. thanks for the help guys! Now i just gotta time the accelerator pump to get rid of the horrible bog!

Yep... do that with the Oring mod. Don't forget to go down a size on the leak jet too. I think stock is 50, I put in a 40.

My bog went away after that.

...and after you fix it try using an oz of Marven's Miracle Oil or Lucas gas treatment ~ an oz or so for a full tank.

It helps reduce the effects of ethanol in the gas that oxidizes the brass jets.

...and after that, start and run the bike once a week (if possible).

gonna do the o ring mod and see what happens. bike will be ridden everyday once i get it registered in my name!

did the o-ring mod, and checked the squirt timing seems to be right on. cold weather here so i think the jetting is off a bit... needs to warm up!!

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