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WR450F Fuel adjustment screw spring/o-ring STUCK!

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Hello everyone!

I am brand new to the dirt bike world and managed to get a my hands on an '05 WR450F with 428 miles! It's basically brand new! I bought it from a friend who had a few other bikes and this one sat for about a year. There was no fuel in it, but the small amount in the lines varnished over. No big deal. I put a few cups of fresh premium through and let it sit while I cleaned up a few other things when I noticed the fuel/air adjustment screw was leaking fuel. It is not the OEM screw, so it was pretty easy to take it out after tilting the carb. 

The issue is that when I removed the screw, the o-ring and spring did not come out with it. With as much as it was leaking, I figured that the spring and o-ring weren't there. There are a few things on the bike that make me think that someone tried working on it, but wasn't quite sure what they were doing. Anyhow, a friend of mine had a few Yamaha maintenance parts in his stock, including a spring and o-ring. I went ahead and put those on the screw and reinserted it into the carb thinking, "hey, if there is a spring in there already, I won't be able to thread this screw in easily." Sure enough, the screw went in without issue. They leak stopped, until we fired it up. We ran it for about 20 seconds before the leak started up again. Just like before. Drip drip drip. So, I went back and pulled the screw and the new spring and o-ring stayed up in the hole. I tried jiggling them out with the screw. No dice. I even took a super thin hard wire and bent a little hook in the end to try to pull it out. Nope.

How do I get the spring and o-ring out without pulling the carb and dissassmebling??

Please help! 

Like I said, I'M NEW. I'm pretty mechanical, but take it easy on me. 

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Fuel shouldn't be able to leak from this spot regardless of the condition of the adjuster and o-ring. You likely have a float valve (ie. needle & seat) issue causing the fuel to rise into this area. Sounds like you're going to be pulling the carb for a proper fix.

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Hey Slug,

Thanks for the response!  I was afraid of that. But that's life, I guess. Even then, do you know how I can manage to get the spring and o-ring out without damaging the "bore" where the screw goes in?

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It seems unlikely that those parts would be stuck that bad - I'm sure once the carb is off and upside down those pieces should come out easily with a bent pick or paper clip. Just make sure that the tip of the needle on the adjusting screw isn't broken off in the carb!

Edited by doug the slug

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Very good! Thanks again. The tip of the needle is still intact. I'll follow up once I dive into it a bit.

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Update:

Pulled the carb and decided that there were a few other little maintenance items that needed addressed anyway. Replaced a the float bowl gasket and the float bowl screws with some heavy duty hex head screws. The float valve needle did not appear to have an issue, but the the float itself needed some adjustment. I was able to pull out the spring and O-ring from the airscrew hole. Ordered a new one on ebay for $12 with all of the hardware...should receive that today. Also, spent $7 on a billet hot start nut. The threads on the OE nut were a little mangled. I'm replacing fuel supply line as it's kinda rigid and would likely crack(eventually) until stress. Replacing all of the gaskets to the petcock assembly as well. Replacing all vent tubing as they are looking to be more on the brittle end as well. I should have this beast buttoned up and ready to roll this afternoon! Looking forward to it!

Thanks again for your help , Slug!

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Sounds good! Here's a tip to check if the needle/seat system is holding: before you mount the carb on the bike, secure it on the bench or in a vice in the normal position. Hook up a piece of clear fuel line to the inlet and fill the float bowl up with fuel right to the top of the line. Once the float does its thing, the fuel should not drop in the line. It is pretty easy to observe this way - even a slow leak will be visible. Do this first so you don't have to go through the agony of pulling that carb off again! Good luck, it sounds like you're on the right track.

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Got it all buttoned up today and runs great! Better yet...NO LEAKS! Still waiting on a few less critical items, but the carb is ready to rock'n'roll! Thanks for your help, sir! Much appreciated.

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