Honda Twins banner

1 - 9 of 9 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter · #1 ·
I've been fighting this for months, but no matter what I do it keeps leaking gas from the over flow tubes. I've adjusted the floats so it should be running super lean, but as soon as I attach the gas tank and allow fuel to flow into the carbs the over flow tubes immediately start draining gas.

Any advice on how to fix this?
 

·
Registered
Joined
·
3,257 Posts
Check your overflow tubes on your float bowls, they could be visibly cracked and in need of repair. Some have slipped a piece of heat shrink tubing over them, I'd use that as a diagnostic test but not a long term fix. Long term I'd solder the cracks.
 

·
Registered
Joined
·
16 Posts
I have a 1982 CM450C, that used to have both carbs leaking gas. I replaced both float needles. After, I replaced both float needles, I still had gas leaking from the left carb. I ended up replacing the plastic float on the left carb, even though it looked ok. Two new float needles and one new float later, my carbs no longer leaked. The fix was pretty easy, because one year earlier I replaced all the float bowl screws with stainless steel metric Allen head fasteners.
 

·
Registered
Joined
·
353 Posts
You can check the plastic by dunking them in in gas to see how they float it weigh them to compare.

Sent from my SM-J320V using Tapatalk
 

·
Registered
Joined
·
1 Posts
I had a carburetor that kept leaking, despite good seals and seats on the fill valves. In my case, fuel would spill into the cylinders while the bike sat. Turned out that the tiny spring WITHIN the needle valve was seized due to corrosion, with no plunging spring action. If your needle valve has an internal spring and pin, check that it freely moves on and out. Otherwise, the float can't fully act on the seal.
 

·
Registered
Joined
·
2 Posts
Discussion Starter · #9 ·
Sorry, I forgot to update. I got the leak fixed. as it turns out the gasket I had in place for the drain screw stopped it from coming out there, but made it leak out of the over flow tubes instead.

I removed the gaskets and backed them in the rest of the way, and boom. Problem solved.
 
1 - 9 of 9 Posts
Top