Float Needle or Drain Screw (Gas Leak)

Here's a bizarre question,
1980 KZ750H LTD
I have gas leaking out of the drain of my #1 carburetor, I was adjusting the float level today, the tank was about 2 feet above the carburetor, The fuel level stabilized where it was supposed to. I put everything back together, But now there is gas leaking out the drain at the bottom.If the float needle was bad, wouldn't the gas keep rising above the spot where it was supposed to level out?
This leads me to belive the drain screw and o ring are bad. The clown that had the bike before has made a mess of the drain screws, it looks like he used a butter knife to tighten them. Is it possible that I just need to replace the drain screws and o-rings? I've had the carbs off three times in the last week, If I can fix this leak with a screw, I'll be pretty happy.

well if the fuel is coming out of your drain's than it sounds like a bad seal there if it was the float level it seems to me it would go out the overflow not the drain. thats just my two cents i am in no way genius when it comes to this stuff tho.


Braden

Yeah, I geuss overflow would go into the airb0x or engine. I was thinking it would go out the drain tube, thanks for making me see the light. I'll get some new drain screws and o rings.

Thanks Man
Requiescat

Requiescat wrote:

Here's a bizarre question,
1980 KZ750H LTD
I have gas leaking out of the drain of my #1 carburetor, I was adjusting the float level today, the tank was about 2 feet above the carburetor, The fuel level stabilized where it was supposed to. I put everything back together, But now there is gas leaking out the drain at the bottom.If the float needle was bad, wouldn't the gas keep rising above the spot where it was supposed to level out?
This leads me to belive the drain screw and o ring are bad. The clown that had the bike before has made a mess of the drain screws, it looks like he used a butter knife to tighten them. Is it possible that I just need to replace the drain screws and o-rings? I've had the carbs off three times in the last week, If I can fix this leak with a screw, I'll be pretty happy.

The fuel level stabilized where it was supposed to.
This could happen where leakage from drain screw location was less than fuel being allowed into floatbowl via the float valve.
This would likely not happen with leaking float valve allowing excessive fuel into floatbowl, because fuel would continue rising to overflow level.

But now there is gas leaking out the drain at the bottom.
Is the gas leaking only from the drain screw or also from the overflow nipple??

If the float needle was bad, wouldn't the gas keep rising above the spot where it was supposed to level out?
Yes, up to the overflow level.

This leads me to believe the drain screw and o ring are bad. The clown that had the bike before has made a mess of the drain screws, it looks like he used a butter knife to tighten them. Is it possible that I just need to replace the drain screws and o-rings?
Messed up drain screw and bad o-ring (leaking from drain screw area) won't cause floatbowl overflow.

If threads on the drain screw itself are stripped (male threads) and female threads in floatbowl remain sound, could replace drain screw and o-ring.

Where female threads in floatbowl are stripped, might try using fuelproof Permatex in threaded area to avoid the leakage until acquiring a replacement floatbowl.

Sometimes the overflow tube inside floatbowl gets cracked, whereby fuel drips out overflow nipples regardless of level inside floatbowl.

Good Luck!

My drain screws have no O rings and they always seeped gas. I just put some hard fiber washers on them and it stopped. If yours have O rings, new ones should stop it.

Requiescat - According to Ma Kaw the KZ750H1 drain screw o-rings are part number 92055-1053 and the drain screw is part number 92009-1095. Both parts are still available. The carb bowls were not sold separately, so if they're stripped you may need to search recyclers or ebay. Good new is - leaks from drain screws are not related to float height.

The carb overflow hoses are normally routed down behind the engine to discharge on the ground (at least that how KZ650's are done). If overflows leak the float valve is probably dirty unless the floats are really riding high or something is cracked. Ed