what causes sinkin floats

[two-stroke-brit]

in the space of two weeks the float in the center carb on my buffalo has leaked ,letting gas and turning from a float to a flood.

i replaced the first one with a spare i had, but that too drowned.
so two questions what causes it and can i relace it with gt380 float or is ir smaller/incompatable.
thanks mark

[crash277]

you need to submerse them is a cup of gas and find the leak and solder it. they have a crack or a pin hole causeing them to let gas in.

[advant63]

if you put the float in a freezer to cool, then quickly to a container of hot water you will see a stream of bubbles at the hole. you may have to do it a couple of times to track a pinhole. don't leave it under water as it will draw water in once the bubbles stop.
if you choose to repair your own, unsolder the centre hole first and resolder it last. it will act as a vent while you repair a seam. work quickly on resoldering the centre hole. if you build up too much heat you will collapse the float body as it cools down. try not to used too much solder as it affects the weight of the float and throws off the level. it appears that the darker float is collapsed.

[tz375]

And remember that the more a float assembly weighs, the lower it will sit, but a collapsed float will displace less gas and a collapsed heavy float will allow enough gas in to leak out of the overflow.

A good trick is to modify a stock float bowl to add a level tube and measure the actual fuel level in a known good float chamber and then check the fuel level (v's teh float level) in the leaky ones. Those that leak will probably have a higher fuel level.

[Coyote]

The float part number for your 73' is 13252-18010 and is still available from Suzuki (about 20 bucks). The part number for a 380 is 13252-11010. That float is probably dimensionally smaller.

[two-stroke-brit]

thanks everyone ,
mark
i will order a spare today.

[GT500Andy]

I ask this question a while ago on the board, why does the float collapse I had a couple on my GT500 go like this, never got a good answer??
Andy

[djfisher22]

what causes sinkin floats

Always being a wise guy, the first thing I thought when I read this thread title was.................


a big ass fish

[GT500Andy]

Yes and a "tench" will push your float up

But nobody knows why the collapse??
Andy

[Coyote]

If you or some PO has forced compressed air into the fuel inlet of the carburetor with the bowl attached, the pressure will collapse the float. Every time.

[H2RICK]

Coyote +++1.
That's a favoirite trick of bodgers to clear out the needle and seat.....instead of diassembling the carb properly.

It can also happen in colder climates IF the bike has stood for a long time and gotten water in the bowls. Water freezes, then expands until -4*C and crushes the floats. Lovely......NOT!!!

As to why brass floats fail, it's usually a combination of thin solder in a particular spot on the seam and then some good old galvanic corrosion happening. The solder gets eaten through by the corrosion, a pinhole forms and.....goodbye.
Dennis' (advant63) procedures for finding the leak and fixing the float are bang on......but when new ones are so cheap, why bother ?? The aftermarket also makes replacements for the Mikuni VM floats so that's another option.
Save the old/bad float(s) and practice your "float repair" technique when you have some spare time this winter.

[advant63]

i was going to add a why bother but everyone should fix one once.