carb float

[ikeholt40]

need help adjusting float can it be done with carbs on bike. i have 79 xs 1100 special. i am restoring it and after tank removal and painting two days later gas is flowing into air intake after starting bike. i drained all four carbs while tapping on them. I can use any help on adjusting carb float while carbs are on bike I really dont want to remove them again. thanks! jarrod

[randy]

Welcome, Jarrod.

You didn't indicate if you had this problem before you removed your tank, but if not, then it seems that some gunk from the tank may have worked it's way into one or more of the float valves.

Or, the float valves were shot to begin with.

The carbs must be removed to set the float levels. Get yourself a good aftermarket manual such as a Haynes or a Clymers. The procedure is very detailed in either manual.

The carb floats are set with the carbs upside down, the measurement is from the flat on the carb body where the bowl gasket sits (measure without the bowl gasket). The setting is around 25mm from the carb body to the highest point on the float. I say around because 25mm is the middle of the acceptable range.

I would suggest that you clean the carbs thoroughly while you have them off. Before closing them up, do the 'blow test' through the fuel lines with them upside down to be sure the float valves are seating properly.

Randy

[skids]

Re: carb float

Originally posted by ikeholt40
need help adjusting float can it be done with carbs on bike. i have 79 xs 1100 special. (snip) I can use any help on adjusting carb float while carbs are on bike I really dont want to remove them again. thanks! jarrod

[skids]

Re: Re: carb float

Opps! Must have hit the send key prematurely. OK, try this. This can remove a particle trapped in the float valve, if that is what ails 'ya. Turn the petcocks to "off." Drain the bowls. This opens the float valves all the way. Close the bowl taps. Open the the petcocks to "Prime." This will hopefully rinse out the particle and fill-up the bowls and properly seat the fuel valves. Turn the petcocks to the normal position. You can drain the bowls again if you think a washed-out particle might work its way into the pilot circuit.

[fxrer]

There is a wealth of useful information on carbs, posted by XS11, a.k.a Mike, in the Maintenance> carburetors section of this site. Be sure to read "carburetor removal" and "re-installing carburetors" which makes the job easier.

[ikeholt40]

Skids no I had no problems at all before removing the tank. I rebuilt all four carbs 2 years ago. I know how much of a pain it is. so I was trying to find a fix w/o removing the carbs. thanks to all for a very quick reply any other help would be great!! I will try to turn the petcocks off and drain because I believe there is just a little gunk or rust in the tank. Then I will redrain bowls and let you know what happens.

[nashville_bill]

IMHO - If you think there is a chance of any rust in your tank you will be fighting a loosing battle until you install fuel filters. Without the filters, you will have lots of problems with leaking gas.

[prometheus578]

If you remove the carbs to check the float level, make sure you remove the floats and needles to check for garbage in the seat. Usual is rust, grit, chunks of deteriorated fuel line... even found two legs and a wing of a fly! Before you reinstall the carbs, check to see if the needle and seat are still good. With the bowls removed, set the carbs upside down and level. Place your fuel tank on a milk carton on the bench and hook it up using extra fuel line. Turn to prime. The weight of the floats should keep the gas from flowing. If it doesn't leak, step outside for a smoke and re-check it in 15 minutes. No leaks? Put the bowls back on, flip the carbs right side up, and let it set again for 15 -20 minutes to see if they overflow. If they leak... time to polish the seats with Q tips and chrome polish, and get new needles.