Carb Rebuild?

[Wheels434]

So I just got this 2003 Blaster and Its in great condition. When I brought it home I noticed that it needed gas so I filled it up. Not 5 seconds after I screwed the gas cap back on I realized that gas was pouring out of the overflow hose on the carb. This only happens obviously when the gas is on. It does not leak when the bike is running. Also it's hickuping and bogs out when I crack down on the throttle. Is this the float in the carb not working properly? Just wanted to get some answers/Ideas of what to look for before I start taking apart the Carb.

 

[Awk08]

So I just got this 2003 Blaster and Its in great condition. When I brought it home I noticed that it needed gas so I filled it up. Not 5 seconds after I screwed the gas cap back on I realized that gas was pouring out of the overflow hose on the carb. This only happens obviously when the gas is on. It does not leak when the bike is running. Also it's hickuping and bogs out when I crack down on the throttle. Is this the float in the carb not working properly? Just wanted to get some answers/Ideas of what to look for before I start taking apart the Carb.

yep, sounds like the float is out of adjustment, or the float valve is gummed up or bad and needs replaced.

try these links.......

http://www.blasterforum.com/carburetor-138/how-clean-your-carb-pics-209/

http://www.blasterforum.com/carburetor-138/float-heights-how-adjust-them-50565/

http://www.blasterforum.com/carburetor-138/easy-almost-free-way-stop-leaky-carbs-33335/

 

[Wheels434]

Right on dude.. thanks.

 

[Wheels434]

So I pulled the carb off last night and the piston on the needle was black and everything else was pretty gunked up. I couldn't really tell if the float was bad or not. How do I remove the piston from the needle to clean it? I have ordered a rebuild kit for everything else.

 

[Blaaster]

If you refer to the pointed rubber tip on the needle, it does not come off.

If it is hard to the touch it may need replacing.

You may be able to clean it up with toothpaste, a mild abrasive.

You can clean the varnish out of the seat by rotating a toothpaste covered Q tip in it.

Drop the float into a bath of warm water to see if any bubbles come out of it, if so replace it.

Adjust the float.

Float level should 20 to 21.5mm on a stock carby.

 

[Wheels434]

Okay, thanks. I'll give these options a try.

 

[Wheels434]

No luck with the carb rebuild. I replaced all the parts that looked like they needed to be replaced but nothing changed with the gas leak. Gas is still pouring out of the drain tube when turned on. Also I cannot figure out how to reattach the black tube that was connected to the carb (opposite side from choke) from the right side of the engine. Is this some sort of fuel/oil injector? I'm at a lose... I have never had any problems like this while rebuilding and cleaning the carb on my RM125?

 

[Blaaster]

Did you remove the seat?

There is an O ring under it which can be the cause of a leak which bypasses the needle.

The black tube is from the oil pump and is the oil injection line.

Pull back the brass ferrule and apply a little heat (not an open flame), the pipe should now press on. Slip the brass ferrule back up the close to the end of the pipe.

 

[Wheels434]

An O ring under the seat? Could you explain more haha. Also I don't remember where the oil injection pipe goes back into the carb. I was a little baked when I when I pulled it out haha Could you also give more detail on this as well?

 

[Larry's Shee]

There is a philips head screw holding a forked shaped piece that holds the brass seat, which has the O-ring on the out side. I'm sure the lincs Awk posted show this. Did you set the float height? Did you clean the needle valve seat?

Lesson to learn here class is don't work on your stuff while BAKED if you can't do it properly.

 

[Wheels434]

Okay.. initialy I could not remove the float pin seat for some reason, it would not come out even after removing the fork shaped holder thing. However, I cleaned the ever living crap out of it as AWKs post described. Im pretty sure it has to be the float. I ordered a new one which will be here tomorrow hopefully. I'm going to take it apart again tonight and look everything over once more, taking pictures along the way so that you dudes can see exactly what everything looks like and a step by step process of what I'm doing. Also there is a large O ring that came with my rebuild kit.. where does this go? and Im still unsure about the oil injector plug that goes back into the carb opposite side of the choke. I need a picture showing me which plug/hole it goes back into. Thanks for all the help again dudes! BTW just put the 5" wheel spacers and some new 20x11-8 rears on the blasty last night. I must say she is sitting mean

 

[Blaaster]

Could that large ring go under the cap at the top of the carby?

 

[Wheels434]

I dunno...Could it?

 

[Awk08]

If it is a flat rubber ring?
That is the Carb cap seal

 

[Wheels434]

I finally found a picture that shows the side of the carb I need info about. If someone could explain the hoses coming out of this side and where they go that would help me tremendously!

 

[Blaaster]

The one nearest the TORS is the oil injection line, the left one is the drain.

Remove that length of blocked off line and slip a cap filled with sealant over the brass nipple.

 

[Wheels434]

Well that takes care of that problem. Now to focus on keeping the gas from pouring out of the drain plug! Thanks dudes.

 

[Wheels434]

By the way that's not my carb. Just needed a good pic to figure out the placement of those hoses. My oil mixer is still intact and will stay that way as long as it works. I plan on checking all the lines tonight as well to make sure none are dry rotted or clogged.

 

[Blaaster]

Be very aware, that if you remove any of the oil lines they will need to be bled free of air before you start the motor.

The complete oil system must be air free.

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Carb overflows are caused by,

Incorrect float level.

Needle not mating with seat because of wear, dirt or varnish.

The rubber O ring under the seat cracked or broken.

Leaky float with fuel inside.

Float supporting posts may be ridged, causing float to stick.

Float rubbing against bowl not allowing movement.

Float arm pinching on pivot bar.

If the float level is correct, does the fuel shut off fully when the float is gently lifted with a finger, with the fuel bowl off?

Float height is 20 to 21.5mm.

If so the problem is not with the needle and seat assembly and may be a mechanical problem, like the float sticking.

Not only spray jets, use a bit of wire broken from a wire brush to poke any debris out, especially the pilot as it has some very small holes in the side.

Remove the seat from the carb, and thoroughly clean the passage where the fuel line comes in.

Make sure the rubber O ring on the seat is not broken.

Put some toothpaste on a Q tip and revolve it up in the seat , to clean out any varnish.

Re assemble and check the float level, 20.0 to 21.5mm on a stock carb.

 

[Wheels434]

Thanks for all the very useful information. Now.. how to bleed the oil line of air? Do I do this before or after hooking it back up to the carb? How do you you remove the seat for the needle float?