Leaking Right Carb

[jazzyrigged]

Finishing up my 78 special for the road and I seem to have a significant leak from the Right hand carb. It was not leaking this morning when I first took it out for a test ride, but this afternoon I took the carbs off and gave them a really good clean. After I installed my new fuel line filter and breather hoses I took it for a ride again and noticed the right hand carb was leaking and it was barely running. I was lucky to get back home without having to push it.

Anyway I took my shower after the sweltering day here in St Louis and I am formulating my attack plan for tommorw. I think I will start with taking the carbs back off and making sure the floats are all set to the proper level. Although it does not seem to do this when it's not running, but it's worth a look.

Can anybody think of something else it could be that I'm not thinking of. Any and all ideas and opinions would be extreemly helpful. Too bad John's not around anymore, he could have solved this problem in his sleep, I know he helped me with so many problems from the 650 rider forum.

Thanks all!

 

[retiredgentleman]

You're doing the right thing by checking the float levels. Have you confirmed that the floats do not have holes in them?

You may need to buy a new float valve needle. The 78's (B38) have metal to metal sealing, while the 80 to 83 (B34) had the vitron tip needle for better sealing. Speaking of xsjohn, he always talked about using a "qutip" with some fine steel wool, inserted up into the float valve seat, and rotate lightly.

 

[5twins]

Many times, dirt or debris can make it's way down from the tank and get stuck in the float needle seat, holding the needle open. When an overflow problem occurs suddenly like yours, this is often the cause. Yes, check the floats but also remove the needle and look for gunk in the seat.

 

[jazzyrigged]

Success! I took the carbs all apart and low and behold I found the float was out of adjustment. A quick adjusting and bingo. Thanks for all the help gentleman!

Now all I have left is to rebuild the back breaks and I am going to be good to go. At least for now I think I have one problem solved.

 

[Ludlow]

Hey guys, I know this is a little after the thread, but I've got a similar problem and just rebuilt my carbs including verifying float integrity, hight setting, and new float valves. If I understand the whole concept, correct carburetor hight and no debris in float valve = no carb leaking, right? Does a '72 XS have some other secret leak causer, or do I just need to keep checking/cleaning? Nothing on this bike seems to get done the first time around, but the new paint looks terrific and I got to test ride around the block yesterday. My last bike was a 75 honda CB200. I had to hang on - grinning. Thanks for any pointers.

 

[gentlemanjim]

Leaking carb float or float needle problem.