Sign in to follow this  
Followers 0
Frank Grimes

Float Needle Valves

14 posts in this topic

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.

Share this post


Link to post
Share on other sites

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

Share this post


Link to post
Share on other sites

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..

Share this post


Link to post
Share on other sites
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?

Share this post


Link to post
Share on other sites

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?

Share this post


Link to post
Share on other sites

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.

Share this post


Link to post
Share on other sites
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

Share this post


Link to post
Share on other sites
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..

Share this post


Link to post
Share on other sites
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..

Share this post


Link to post
Share on other sites

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

Share this post


Link to post
Share on other sites
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?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0