Float issues

[JoshP]

I've been having a major issue with my float. I have set the float so many times now I can't even count. I have even had a bunch of friends set it as well, but the same outcome each time. I re-set the float level Saturday took the bike out for 1/2 hour with no issues or leaking. Took the bike out Monday and it was pissing out even while I was riding. Basically even though the float is set to what my manual stated, gas is pissing out of the float tube. I've never had a carb problem like this and I'm running out of ideas since I have set the level probably 20 times at this point. Any ideas? Nobody say check the float level either!

 

[eff]

How long do you let gas sit in you carb?

Ethanol is wreaking havoc on all kinds of vehicles. Using a stabilizer is more important then ever and if your bike is going to sit you need to drain your carb, even if it's two weeks.

Which reminds me I need to do mine. My bike leaked for the first time this summer and it had only sat for three weeks with stabilizer. I drained after that and the problem was gone as fast as it started.

 

[JoshP]

Thanks Eff, Nope the gas is brand new. The weirdest part is that I will take the carb apart, check the level, reinstall it and no leak, ride a little and no leak. Then when you go out for the day of riding it will start leaking as the ride goes on. Really annoying. If carbs weren't almost 700 bucks I would just buy a new one. I'm curious if the float assembly or some of the other parts in the float are shot.

 

[fury1]

when you take the carb apart is the float still at the correct level? if it is,assuming it doesnt have any pin holes in the float and taking in gas(which you should feel if your removing the float)it sounds like you needle vavle is either worn or sticking(dirt) up too high,you probably have cleaned the carb out already,but you may have picked up something along the way,do you have an inline fuel filter? maybe a clogged vent?how clean is your airbox behind your filter?

 

[eff]

I have a friend at a Yamaha Dealer in NH and they have had to rebuild a large number of carbs this year.

I would start with cleaning the needle (might need to be replaced) and seat. I'd also check to see that your float still floats.

 

[cdn280]

Replace the needle/seat and make sure the carb is 100% upright and not tilted. My 06 has not leaked since adjusting the float height from new. It came set as high as it would go.

 

[Gonzo]

it might be worth checking any o-rings or rubber seals that are in the carb as my old suzuki 125 suffered this continually until i pulled the carb completely to bits and found an o'ring had perished letting fuel through from the tank continually.

 

[onebrow]

Check that the float pivot pin/axle is not too loose. I have heard of carbs where the pivot becomes sloppy in the towers that support it. When this happens you get varying float heights.

 

[jeffd]

Someone noted previously that the float can be twisted slightly - so the left side of the float is not the same height as the right etc. To ensure that this isn't happening - check the float height from both right and left sides of the carb. (I think eric k gets credit for this tip).

jeff

 

[bobr]

I have a friend at a Yamaha Dealer in NH and they have had to rebuild a large number of carbs this year.

I would start with cleaning the needle (might need to be replaced) and seat. I'd also check to see that your float still floats.

yup, he's correct. we've had a huge problem. new bikes that have sat for as little as 2 weeks have had stuck or etched float valves. pay close attention to the valve. if it has 4 raised edges running parallel from top to bottom of the valve and have any marks on them at all it will cause them to stick. i've seen valves with the tiniest marks that would hang up. it's recommended that the fuel be drained from the bowl if the bike is going to sit for a week or more. also use a fuel stabilizer that prevents corrosion.

 

[lvermey]

Gas draining from float needle.

I just bought an EC 300 08. The guy I bought it off of told me that he had put some tripple tapper needle in the carb for better performance. He told me that gas was coming out of float needle over flow. He told me to make sure to turn the tank off when I stopped. I would prefer to have it working properly. I have read all of the possibles in this thread to check on, which I will do.(Float aready done). What he told me a friend of his who had the same problem did was to bend the float needle tang that it hangs on just a bit in the proper direction to make sure the needle was seating properly. Is this a good idea or not?

 

[iancp5]

I just bought an EC 300 08. The guy I bought it off of told me that he had put some tripple tapper needle in the carb for better performance. He told me that gas was coming out of float needle over flow. He told me to make sure to turn the tank off when I stopped. I would prefer to have it working properly. I have read all of the possibles in this thread to check on, which I will do.(Float aready done). What he told me a friend of his who had the same problem did was to bend the float needle tang that it hangs on just a bit in the proper direction to make sure the needle was seating properly. Is this a good idea or not?

It's a good idea.

Try and do it a tiny bit. In theory you can set the float height exactly off the bike and it's done by bending the tang & measuring. I've never had much success this way and it always leaks so I set it by the book then move it just enough to stop it leaking. Must be the way I measure or my old worn needle valve.

 

[moto9]

Check that the float pivot pin/axle is not too loose. I have heard of carbs where the pivot becomes sloppy in the towers that support it. When this happens you get varying float heights.

This is so true, I have seen it several times, my fix in this case is to JB weld the holes closed and re-drill them.

I never go by the manual specs when it comes to float level for trail riding because the bike is all over the place hopping logs etc and with a 2 stroke it's more important to conserve on fuel than say MX.
I usually go a few mils past the factory specs and test ride and so on until it stops pissing...then I do some WOT runs and make sure it doesn't starve for fuel.
It took me a couple of trys to get my CR 250 to stop pissing and it's way past the factory specs.

 

[gasgasman]

SUDCO has carb rebuild kits for $40.
The float is $16.

The float tang that operates the float needle needs to be parallel with the float needle.
Like it shows below.

This is critical because the tang will push the float needle over to the side preventing the seat from sealing.
The Gas Gas carbs are not horizontal like most bikes, that's why we have issues with the fuel dribbling out.

 

[Noel]

Fine sand particles

Hi Guy's

I had the same problem with my 07 250 ec. I replaced the needle, adjusted the float, cleanned and re-cleaned and still fuel over flowed. Due to my bike having a in-line fuel filter I thought that my fuel was cleaned. In the end I took off the tank and fuel tap, to my surprise it had a huge amount of very fine sand particle's. I could hardley see them but I could feel the grit. I cleanned the tank so many times, replaced the fuel filter. No more problems.
I went looking for the harder issues to resolve, keep your investigation process simple check off the easy reviews first, take this advice from someone who did the opposite spent too much time & money and didnt check the most basic requirement "clean Fuel".

Noel

 

[gasgasman]

The Gas Gas carbs are not horizontal like most bikes, that's why we have issues with the fuel dribbling out.

I looked at some KTMs today and their carbs are at the same angle as ours.

Anyway.
My carb has been dribbling fuel a lot lately.
I replace the float , all the gaskets and the float needle.
Rode today and the dribbling is gone. The bike totally rips like it used to.

 

[gasgasman]

had a huge amount of very fine sand particle's.
Noel

Dirt can also enter through the carb vent hoses.
This filter kit would be the hot set up.

http://www.7602racing.com/prod_t6cf.php