Jonway YY250T CF 250 cc with 30 mm carburetor Carb rebuild By rcapete007 (Read 4,489 times)

[rcapete007]

Anyone have instructions for rebuilding a 30mm carburetor? including float adjustment specs and how to set it?

[Bashan]

How about a new one for $37.00? or you can Google rebuild kits and they're about $20.00.

There's a float adjustment tutorial in the carb section of the Library. Not to be a smart aleck but you pretty much take them apart, take pictures as you go so you remember what you did, clean everything, and use the new parts to reassemble if you're using a kit. Unless they're really old or really gunked up they usually don't need a rebuild.

What's it doing to make you think it needs a rebuild? I actually need to clean a CF 250 carb and I could do that tomorrow. I need something for the tech section so I'll see if I can get some pix and post them but it might be a couple days till it gets up.

[Alleyoop]

Yep, unless the carb is really old no need it just actually needs adjustment, but even a new one you will have to adjust. But hey it's your dime

[rcapete007]

Its the carb I wrote about about 3 weeks ago its dumping gas out the overflow hose on the top. That's why I need the float info so I can set it properly so it doesn't overflow again.

[rcapete007]

I did get a new one for 35.00 but now have the old one and bought a rebuild kit from china for 6.00

[Alleyoop]

[Bashan]

If it's dumping out the vent it's a bad float valve. It might just have some crud in it. The adjustment isn't going to change to do that. Something happened to the valve. I'll post something tomorrow for you. It'll get me moving on this CF 250. Rich

[Alleyoop]

We all know that CARNAC I think they do, but maybe not, anyone with any kind of worms up there would check to see if the fuel inlet where the float moves the shut of valve into would make sure it is clean as well as the tip on the valve itself. BUT THEN AGAIN I think you better further explain it with pretty pictures and flowers and a yellow brick road(rofl). I guess I assumed to much
DANG BLEW IT AGAIN

[Guitarman]

Gee Alley, Don't hold back now... Just tell us how you feel...

[Alleyoop]

Not a problem BRO I am blunt at times and sometimes I will sugar coat things. The sugar coating happens only usually to the real noobs have to be gentle with them The ones that should know better get the fire breathing dragon and even then It all depends on the questions and problems and if I haven't taken a dump or not

BUT JUST REMEMBER I WILL HELP YOUR POOR arse OUT OF YOUR JAM IF I CAN So don't be offended by my straight shots just get pissed and learn is all we ask. So you then can help others with what you learned.
Alleyoop

[Guitarman]

[Bashan]

What I meant Alley was that the float adjustment wouldn't somehow change on him for no reason. I mean something would have to bend the plunger or something like that and there's just not a lot going on in the float bowl to do that. My point was if his float adjustment was good before and he didn't open his carb up, why would it be different. I worded my response poorly. I'm uploading a video right now on the first phase of cleaning the CF 250 carb. I'll do the cleaning and reassembly tomorrow. My fame as a Seinfeld hand model will be epic.

[Alleyoop]

I agree so the only way that carb is flooding is due to the valve not sealing the fuel inlet. So I would suspect a really old carb with the rubber pointer damaged or deteriorated or all gummed up as well as maybe the inside of the fuel inlet or a leaking float. Or if that scoot was knocked down the pin holding the float may have partially come out of one side IF it has the pin type holder and maybe binding the float so it does not rise as the fuel is pouring in.
But won't know until it is opened up to find the problem.
Alleyoop

[richardv]

I say it's the ethanol. It destroys every thing it touches.

[Bashan]

Here's part one of the video, I'm not real happy with it but I am NOT reshooting it! It took 4 hours to upload! I'll make things clearer on the reassembly video and get some detail pix:

vimeo.com/102882974/download?t=1407455378&v=277168054&s=2104cf5f77eadfe75fbc2f77e4df6903