Topic: SO TIRED of leaking gas

[Tugboat]

PD carbs on my '77 750K. So this problem used to be related to a missing float bowl o-ring for the accelerator pump on carb #2. Replaced that, and replaced the float needle and that seemed to fix the problem. Sprayed all jets with carb cleaner while I was in there. Then I was having some fuel delivery issues (#3 wasn't getting enough gas) so I took the carbs off again this weekend, took the bowls off 1, 3 & 4 and sprayed carb cleaner & compressed air through all orifices. Put it back together last night, took it out for a lil' shakedown and it does indeed run better. Still need to sync the carbs and sort out timing but it was a definite improvement.

When I got home, I shut off the gas and pulled into my garage. About a minute later, gas is dripping out the overflow tube for #2. Ugh. So I drained it into a gas can... still more drops of  gas. I removed the fuel line from the carb rack to make sure my NEW petcock wasn't leaking (it wasn't). Still dripping. SO WTF?!? Is gas from the other carbs making its way back into #2 and causing it to overflow?! Seriously, I'm SO done with this thing right now. Any advice would be appreciated.

[bollingball]

Tug: Even if it were coming from the other carbs it should not over flow. Your float valve is not shutting off or the float level is to high.IMO
Looks like you need to go back to square one Tank clean filter good? these carbs do not handle thrash at all.

[coma13]

I've been having the same problem and it appears that my drain screw was the culprit. not sealing properly. The little o ring is thrashed and the seating surface at the tip was pretty rough. i wrapped it all up with some teflon tape and that stopped the leakage. Total ghetto fix and I am sure the gas will break down the teflon tape but it is helping for now.

[KingCustomCycles.com]

If you have a persistent, and difficult to find drip, it is often a cracked or pitted copper overflow tube inside the bowl.  Solder will fix it. No need to remove the rack or anything drastic. BTW, modern carb cleaners are worthless, I consider them $3.00 worth of compressed water basically.  I manually clean all orifices with wires, qtips, properly sized drills, scotchbrite pads, brass wire brushes, etc.  and then use compressed air with a rubber tipped nozzle to clean and verify flow. Be careful not to oversize or scrape anything critical with the cleaning.  You'll get it, hang in there.

[dtmmil]

I second the copper tube inside, take the bowl off, fill it with gas and let it sit and see where, if its leaking. I use the carb cleaner in the gallon can with a basket to soak my carbs when I clean them, depending on how dirty they may soak for a day or 2.

[KingCustomCycles.com]

I second the copper tube inside, take the bowl off, fill it with gas and let it sit and see where, if its leaking. I use the carb cleaner in the gallon can with a basket to soak my carbs when I clean them, depending on how dirty they may soak for a day or 2.

I have a gallon can of Gunk from 1986 that I still use for soaking jets.  They don't make it like they used to.  I remember it just about killing me to cough up the $29.00 back in the day.  One of the best $29.00 I ever spent.

[dtmmil]

I agree with you there also, its not made like it use to be, no where near as strong.

[Tugboat]

Like I said, I drained all of the gas out of the #2 bowl and verified that no gas was coming out of the petcock. So how did the bowl fill back up and start dripping again? The amount left in the tank-to-carb hose couldn't hold enough gas to fill the bowl again.

[mrrch]

On the side stand carb #3 & #4 can drain gas back down to # 2 & #1. Not very much if the petcock is turned off but a little bit.

[Trav-i]

Hey Josh,

I recently learned that the fuel drain out the overflow tubes not only if they overflow, but also if you pull the bowl drain screw (a weird bottom drain setup).  Only thing I can think of is that the hose is draining into #2 float bow(since that's where the inlet is), and it's getting past the drain screw and dripping out. I had simmilar problems with my carbs too, due that dirty gas tank.  Which I have now fixed, I cut it open and had the inside bead blasted.  I'm just wating on Chris (Fabricator) to get it back together for me.

Hope you get it all sorted before Barber.  I'm hoping this fixes my problems.

Travis