float help

[Guest]

I have a 1977 gs750. I have a sportster bobber gas tank and it no longer has a petcock cause it will not fit in the location it needs to be so it is now gravity fed. My #2 carb is overflowing like the float is stuck but I have adjusted it many times and no difference. My question is would it being gravity fed now affect that or would the float shut off the fuel flow if at proper height? And what way should I adjust the float?

[Agemax]

if you have tried adjusting the float level with no luck it sounds like the float valve isn't sealing correctly. take it out and check if it is worn or just stuck with goop. if it is worn, replace it.
if you are unsure of its integrity, swap it with the float valve on carb #1 and see if the overflow problem transfers to that carb.
also make sure the float itself isn't punctured!

[GregT]

What he said - plus, at least put an inline tap in the system for safety's sake.

[1977jonc]

I have an inline petcock if that's what you mean. it just doesn't need the vacuum line anymore so it makes it gravity fed.

[jsandidge]

I have an inline petcock if that's what you mean. it just doesn't need the vacuum line anymore so it makes it gravity fed.

The ones with vacuum lines are also gravity fed. The vacuum just pulls on the diaphram allowing the gravity fed flow of gas. When there is no vacuum, the diaphram returns to a closed position. The vacuum doesn't actually pull gas. Make sure you shut off your petcock when the bike isn't running or you could fill your crank case with gas. Not a good thing.

[81GS850]

if you determine the needle valve is suspect, I would suggest getting the finest grit you can find, or better yet rubbing compound and try to smooth out the needle. If you need to buy a new needle and seat I would try everything else first.