Carby Gas leaking where fitting attaches to carb

Thanx for all of the posts guys-very informative! I checked the float level and it was around 3mm low-reading 18mm instead of 21 mm. These brass levers just don't seem to keep their adjustment that wall-at least that's been my experience. Still looking for a source for the fibre washers-Gearhead222
 
Dear Fellow Members-After searching the local nut and bolt house and several auto parts stores, I FINALLY found some fibre washers after scrounging through several old carb rebuilt kits at my crazy Iranian mechanics shop. Gasbike.net doesn't carry them-you'd have to buy a carb to get the washer.I even checked the local motorcycle shop where I buy my synthetic 2-stroke oil. If ANYBODY knows a source, I'd like to know. Current rubber O-ring is holding up well. I realize that these carbs are cheap, but would like to know if there are any gasket sets out there for these carbs. It's labor intensive and a waste to me to replace a well running carb just because it has a bad float bowl gasket, fibre washer or other bad seal that can be fixed with a replacement gasket or seal-Gearhead
 
its a common fibre gasket/washer, available from fastener supplies. or engineering supplies. etc.
about 10c... but usually a pack of ten... should even be in the local hardware in plumbing...

but the washer isnt the isssue.

look at the object...its basically a brass TUBE.

the fuel in the bowl is BELOW the thread. fuel, like water, dont go uphill!

the thread is below the washer. so fuel wont normally ever touch the thread, hence the washer is unnessecary. the thread never has to SEAL.

if there is fuel leaking around here...have you clamped the hose? the hose doesnt have a tiny pinhole? the tank isnt leaking from one of the studs and throwing you off the track?

youve already checked the fuel height apparently, so...

the only other thing possible, which i refuse to believe, is the brass fitting is cracked...
 
Dear Sir-Replaced the fuel line, adjusted the fuel float level and replaced the paper gasket. Brass nipple and carb body appear fine. Bike is not leaking now. Keeping fingers crossed:)-Gearhead
 
I can tell you what I did in my experience about this.

That screw at the bottom of the carb leaks. It's leaked on most of the builds I do. Common sense tells me that the purpose of that screw is ONLY for draining the fuel before removing it and tinkering - it could serve no other purpose. I too tore down and rebuilt my carb many times in hopes of finding a leak around the gas intake nipple or gasket, but alas, no dice. So, I just leave it alone and let it drip!

The solution I found for this is... turning off the petcock from the tank! It's a pressure driven fuel line powered by gravity, this is why there's no fuel pump, this is why the tank is above the motor. When you stop the pressure from pushing gas unrestricted (due to the gas tanks venting), it will leak for a minute, but all that will leak is the gas that has collected under the float, and even then - not all the gas from that chamber will leak out! So, if you're turning off your petcock and you see leaking, that's why - don't freak out.

Personally, I don't mind the leaking. It's leaking unburnt fuel out of the exhaust and out the carb drain screw. Eh. I leave the petcock on all the time (with the exception of storage for weather reasons). The reason I leave it that way is so that when I fire it up the next morning it fires up immediately without setting the choke. I know it's slightly irresponsible maintenance, but there's a reason behind it at least.

NOTE!!! If you see a leak like this, it is a VERY MINOR leak. If you are noticing a very MAJOR LEAK, then check your gas tank and fuel lines. My first build I didn't think twice about mounting the gas tank above the metal brackets for the brake line (the ones welded to the frame). After a season of riding I lost a full tank in about an hour while it was parked, and there were two holes! One was about 2mm, the other about 1mm. The vibrations of the motor caused the brake line brackets to bore holes. I was able to remedy this by JB Welding the holes shut, and placing 5 or so strips of denim between the tank and the frame. I considered using a cut tire, which would work better, but denim was more easily accessible. So, before you diagnose it as the carb drain screw, be sure you have checked everywhere else!
 
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Dear Sir-I've stopped the leak between the brass fitting and the carb with another paper gasket, and just noticed ANOTHER leak where the fuel line attaches to the gas filter. I think that the main problem is the cheesy spring expansion type 1/4" fuel line clamp that has the 3 ears that you squeeze with pliers to open. Does ANYONE know of a good source for quality 1/4" spring or screw type fuel line clamps? Cannot find anything locally. Should I even use a separate fuel filter? Getting rid of this filter would decrease my leak probability.
As always, thanx again for any feedback-GREAT forum:)-Gearhead
 
Well, maybe you should get some different fuel line and just a metal screened filter. I just got gifted a metal screened one yesterday, so I can say good bye to my paper filter.

I say get some wider walled fuel line (same tube inside, about 3/4 - 1" diameter outside), and just get some small standard threaded hose clamp.
 
The fuel line that i use is 1/4 inch inside diameter and it's clear. It's made and sold for lawnmowers and is sold at auto-zone.
once you put the line on, and it comes in contact with gas, it slightly shrinks, making a leakproof seal and no clamps are needed. the line is soft and felxible when it's newso it's easy to bend without kinking. Once it's on it does get slightly hard over time and it will hold it's shape. I have not had a leak yet and i've had the same line on one bike for 2 years, and on another bike for almost a year.
I use clear mini fuel filters that are slightly bullet shaped and they have a fine screen filter inside. They are also for lawnmowers and sold at auto-zone.
 
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Or you can go to any motorcycle shop and get 1/4 fuel line for about $1 a foot and a stainless steel screen filter for about $5. $7 out the door and your set up. The hose I got is a clear blue and the filter is clear so you can easily see any crud build-up. No clamp needed.

If your useing the stock fuel tubeing throw it away, it's junk.:poop:
 

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