Float Needle Valves

I think the needle valve on my 426 is bad is there a source where I can buy just the needle? There is a kit but it is like $56 and has a bunch of parts I don't think I need.

The needle seat from '03 onward is not serviced, and so the needle for those carbs is sold by itself. I do not know if an '03 needle will work in a 426 carb, but you might have a look at one. PN= 4MX-14392-00-00

Why do you think the needle is bad..?? I just checked mine on an 01 426...It was leaking fuel...I replaced the o ring..its fine now..

same as above had fuel leak replaced O ring all good now:ride:

Why do you think the needle is bad..?? I just checked mine on an 01 426...It was leaking fuel...I replaced the o ring..its fine now..
So the 450 O-rings did actually fix your 426?

I assumed it was the float needle since the carb fills with so much fuel and drains a ton of it out.

I forgot to mention mine is a 2002 YZ426

Was this similar to your fuel problems?

What O-ring did you guys use?

Sorry if I'm stating the obvious and you have already checked, but make sure your floats are adjusted correctly. I've found that after several years, float settings tend to drift a little, almost always higher. All the whoops and jump landings eventually take a toll on that tiny tab of metal.

I assumed it was the float needle since the carb fills with so much fuel and drains a ton of it out.

I forgot to mention mine is a 2002 YZ426

Was this similar to your fuel problems?

What O-ring did you guys use?

yep mine is a 2002 was leaking excess fuel, O ring was stuffed it looked more like a plastic washer than a rubber O ring got mine for free from a specialist O ring and gasket company here in nz

So the 450 O-rings did actually fix your 426?

Dont know yet....i just ordered them today...these were for the inlet...

I replaced the needle valve o ring last week and it stopped the leaking from the overflow tube...Ill post results when I get the 450 0 rings in for the inlet..

I assumed it was the float needle since the carb fills with so much fuel and drains a ton of it out.

I forgot to mention mine is a 2002 YZ426

Was this similar to your fuel problems?

What O-ring did you guys use?

More than likely its the o ring around the needle valve....Yamaha wont sell them, they want you to buy the needle valve and seat complete for 75.00..

I bought mine from Sudco....Problem there is they have a 25.00 minimum order...If one is leaking...more will soon...Go to their website and look at their schematic...Pick out several different o rings....get the 3 at the inlet, those will go soon..they did for me..

An alternative might be to buy a complete gasket kit for a CRF from Honda for $18 or so. The PN for an '02 is 16010-MEB-671

An alternative might be to buy a complete gasket kit for a CRF from Honda for $18 or so. The PN for an '02 is 16010-MEB-671

Are they the same? Have you tried it? If so that would be awesome.

Does anyone have a part number for the O-ring or the dimensions?

Can I just use a hardware store O-Ring? If so what size?

Can I just use a hardware store O-Ring? If so what size?

I couldnt get any to work...So I ordered it from sudco..

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