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Jeremy61761
04-24-2013, 10:46 PM
168227

My carb leaks fuel through the overflow. One idea is that the float is bad.

Can any trained eye tell if it is a bad float? I don't know how high it should float...

Any help is appreciated!

yaegerb
04-25-2013, 12:01 AM
Could be a number of things. Needle off of the float isn't seating, bad float (see if they float in water, dunk to check for holes) or it could be a plugged main jet (blow the main and pilot jets out with compressed air).

falloutboy
04-25-2013, 01:55 AM
chances are it's either the float needle not sealing or the float height needs adjusted.

3wheeled roofer
04-25-2013, 09:34 AM
chances are it's either the float needle not sealing or the float height needs adjusted.


yup......what he said. just messed with mine on my 500 conversion. mine runs on methenol and it dries seals on everything.

Jeremy61761
04-25-2013, 08:18 PM
I had a little more time tonight. Looked close at the bottom of the carb, and sediment all over. I'm thinking step one is a fuel filter now.

$35 for a float that may or may not work. $90 for a new carb.

Thinking hard about just buying a whole new carb. Hate to drop the cash, but also hate to spend the summer trouble shooting instead of riding!

falloutboy
04-26-2013, 02:08 AM
take the time to work on what you have. If theres crap in carb the tip of the float needle is probably worn.

go buy a float needle to start. if it has sat for a while, it probably needs it, either way, can't hurt. I think they are like $10-$20 so it's MUCH cheaper than a new carb. You can test it by reassembling your carb but leave the bowl off.

-blow into the fuel inlet with your mouth. it just takes a little bit, so no air compressor needed.
-manually raise and lower the floats. if you can not keep blowing when the floats are raised, you're float needle is sealing.
-also use this procedure when adjusting float height. You basically want the floats to be parallel with the bottom of the carb.

Adjusting float height: If its still leaking out the over flow, bend the little metal tab that the float need rides on. If you're holding the floats in the working position (metal bracket on top, like in your picture), bend the tab up just slightly, it's easy to go too far, then you'll be running out of fuel. Ideally, you want the flow to stop when the floats become level.

There is a specific way of doing it in the manual but this is how I did the carb on my 85 and haven't had a problem since I adjusted the floats when I first bought the bike 3 years ago.

Hope this helps!

barnett468
04-26-2013, 02:32 AM
Hello


I can not view your photo so I don’t know what type of carb or bike you have.

All good suggestions from above however I do not understand the purpose of placing the floats in water to see if they sink. Perhaps if he sees this he can tell you more specifically the purpose of doing this.

xxxxx

I had a little more time tonight. Looked close at the bottom of the carb, and sediment all over. I'm thinking step one is a fuel filter now.

Yup.

xxxxx

$35 for a float that may or may not work.

Once your floats have been exposed to fuel for 30 minutes or so you can simply remove the float bowl pour gas in it and see if they float. If they totally submerge they are bad. If they float they are useable.

xxxxx

$90 for a new carb.

Again I have no idea what bike you have. A new Chinese carb for many bikes is $29.95 on amazon.com. They seem to work fine but occasionally require jetting.

xxxxx

Thinking hard about just buying a whole new carb. Hate to drop the cash, but also hate to spend the summer trouble shooting instead of riding!

Trouble shooting doing ALL the tests above takes from 45 minutes to 1 ½ hours hour. It will take you much longer than that to order the new one install it then rejet it if neccessary.
I can not view your photo so I don’t know what type of carb or bike you have.

All good suggestions from above however I do not understand the purpose of placing the floats in water to see if they sink. Perhaps if he sees this he can tell you more specifically the purpose of doing this.

Jeremy61761
04-26-2013, 06:24 PM
The trike is a 1984 Yamaha 200 EL. The float does float, but roughly half is submerged. I plan to add the fuel filter this weekend. I will adjust the float based on suggestions above as I go.

She seems to run fine until it leaks. Generally after I kill the power.

Thanks!

tri again
04-28-2013, 02:14 AM
Depending on the model and year, it could have a spring in the float needle too.
Impeccable cleanliness is important.
Not a bad idea to clean the tank real dry and blow it / rinse it out, so you don't have to go through this again.