Carb leaks gas out the drain

KZ802 · Posted: Mon Jul 21, 2008 9:18 pm Post subject: Carb leaks gas out the drain

I have a 1980 KZ 750-4. Kehin carbs. The inner left carb leaks gas out of the drain when it's running. The bike leans over pretty far when it's on the side stand. (leans left) I'm thinking maybe some crud is stuck in the carb so the floats can't come up. Seems like if there was any sediment it would affect that particular carb first. Or the floats have a hole in them so they become gas-logged and don't float. Does this sound like I'm on the right track at all? I'm new to working on carbs. Any help would be appreciated.

gaj55 · Posted: Tue Jul 29, 2008 9:03 pm Post subject:

First get rid of crud and be sure to check with the overflow tube - they crack!

KZ802 · Posted: Tue Jul 29, 2008 10:08 pm Post subject:

They don't even have the rubber overflow tubes on them- it leaks straight out the nip. you mean the metal tube in the bottom of the carb body?

gaj55 · Posted: Wed Jul 30, 2008 11:11 am Post subject:

70s Honda carbs have a brass overflow tube that extends out the bottom of the bowl and becomes the nipple for an overflow line. It can get a not so obvious crack in it that will drive you nuts and make you think you have a stuck float. Typically you discover the crack after losing most of your hair into your tightly gripped fists. I have asked several mechanics and no one had an answer for a fix.

I have to plead ignorance to the Kaws. I was hoping to give you something more to look for.

Good Luck

KZ802 · Posted: Tue Aug 05, 2008 7:08 pm Post subject:

So, I opened the drains on the left side carbs (the ones leaking) a few minutes before I tried to start. Then I started the bike and it leaked gas out of the right carbs. Could the floats all be getting gas logged? am I gonna have to drain all the carbs after every time I ride until I rebuild them?

gaj55 · Posted: Tue Aug 05, 2008 7:43 pm Post subject: leaky carb

The old trick is to rap the side of the bowl to unstick the float. If that doesn't stop the leak then - yes - you need to rebuild the carbs, rest the floats - etc....