Can't stop gas leaking past float needles

I have polished the brass seats, replaced floats and needles abet with the less expensive kits you see on Amazon and eBay, hung a test tank with carbs in a plastic tray for hours with no puddles, reinstalled and started/idled then shut off the petcock. A week later hydrolock

Do I need to find OEM carb parts or will K&L work? I read somewhere K&L is now rebranded Chinese parts, I don't want to pay extra for that. Man a single carb is starting to look like an attractive option.
Also where is the fuel pressure coming from with the petcock off and filter/pump below the carbs?

Do you still have your original needles? If so, clean the rubber tips with emory cloth (sands the rubber off) to remove any hardened gunk and try them back in the carbs first. How does the gas get past the petcock when closed? Well, that has always been a mystery with classic goldwings. My '82 had the same issue sitting in a garage and then hydro-locking. I recleaned the tips of the needles and that helped. The only thing I was able to discover is the tank would pressurize when sitting from temp changes in the garage. I had to clean the gas cap to remove rust from the vent. When the tank pressurizes, it pushes gas past the petcock.

My experience with 6 sets of carbs is...only oem float valves are reliable. This is the setup I use to see what level the bowls are at when the float valves close. The clear tube is connected to the bowl drain (open)

OEM (even used) float vaves, and fix the petcock so it doesn't leak.

I would agree that the original carb parts should be used. Do you or a friend have a ultrasonic cleaner? You can get a cheap one at harbour frieght. I use pinesol for a cleaner, but there are many cleaners that erveryone will swear by. Oem parts are held to a much closer tolerence then knock offs

How was that carb float level tube thing done, it looks like the drains were drilled for barb fittings.
I think the petcock is indeed leaking due to the tank pressurizing. A new fully vented fuel tank cap is on the way, the measurements from the diagram are spot-on so hopefully it fits.

https://www.motomentum.com/2fastmot...ome-fuel-tank-filler-cap-17620-402-010-139657

You can get good float needles here Misc Carb Parts for GL Models Special O-Rings and Seals , use the original seats. Randakks did have petcock rebuild kits, the rubber dries out and cracks and will let gas leak past.

K&L parts have always been from the Orient.
Several years ago, Mr Lee opened a factory in N Korea.
Makes all sorts of equipment to work on motorcycles
They sell very good parts, many shops use their parts.
Then charge yuo full price for stock Honda parts
Have used them for years, always with great results.

Im having the same problem with my 82. Used new K&L float valves. Cant get them to seat reliably.
I have a set of new OEM valves coming. Still have the original seats but they are so gummed up I dont think I could ever get them clean. I hope the K&L jets are better than the float vales.

Now apparently I need to be concerned about the petcock. Tabk is empty now.

Motörhead said:

I have polished the brass seats, replaced floats and needles abet with the less expensive kits you see on Amazon and eBay, hung a test tank with carbs in a plastic tray for hours with no puddles, reinstalled and started/idled then shut off the petcock. A week later hydrolock

Do I need to find OEM carb parts or will K&L work? I read somewhere K&L is now rebranded Chinese parts, I don't want to pay extra for that. Man a single carb is starting to look like an attractive option.
Also where is the fuel pressure coming from with the petcock off and filter/pump below the carbs?

Click to expand...

oem is best. i have used K&L stuff for decades and always happy. but for float valves on anything, i will use OEM if its available.
rebuild the petcock, as stated above, the oring quits sealing, and the valve itself will gunk up and push itself away from the surface.
the tank is under constant pressure while running, and if the cap is good, the tank remains pressured for dayyyyyys! run the bike for a few minutes down the road. when you turn off the engine, open the gas cap. you year whoosh! as the pressure is relieved.

I've had Japanese motorcycles off and on since the 1980's and never had so much trouble with petcock and carb fuel leaks, had similar trouble last year with a Kawasaki ZG1000 Concours. Is it the age, high levels of ethanol, or both?

It is possible that the needle and seat are working fine, but the gas is leaking between the brass seat
and the carb body.

Motörhead said:

I've had Japanese motorcycles off and on since the 1980's and never had so much trouble with petcock and carb fuel leaks, had similar trouble last year with a Kawasaki ZG1000 Concours. Is it the age, high levels of ethanol, or both?

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It is both age and ethanol gas.

Ordered this petcock, will give a short and long term review on that and the cap for the benefit of others

Motörhead said:

I've had Japanese motorcycles off and on since the 1980's and never had so much trouble with petcock and carb fuel leaks, had similar trouble last year with a Kawasaki ZG1000 Concours. Is it the age, high levels of ethanol, or both?

Click to expand...

I ran into trouble with my 1100 a couple years ago and found the aftermarket ones seem to come with rubber o rings at the floats, the factory ones use metal, once I replaced the o rings I quit having the issue.

Motörhead said:

Ordered this petcock, will give a short and long term review on that and the cap for the benefit of others
View attachment 49226

Click to expand...

you have worked on japanese motorcycles for decades, and you ordered a part that can set your balls on fire, from sabercycle?

claydbal said:

you have worked on japanese motorcycles for decades, and you ordered a part that can set your balls on fire, from sabercycle?

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I wasn't aware there are differences in Chinese vs Japanese pot metal.

My original 1200 has viton tipped rubber on the float valve needle tips. If the needle tips dry out from no gas present in carbs over a long period, the rubber in the tips slightly shrinks. This can cause overflow leaks when the needle tips are first exposed to the gas after a long storage period with the tank valve shut. I have found I need to have gas to and in the carb bowels, then shut off tank valve to remove tank pressure while I let rhe valve tips reswell a day or so. Then on reopening the tank valve, no more overflow leaks occur.

Motörhead said:

How was that carb float level tube thing done, it looks like the drains were drilled for barb fittings.
I think the petcock is indeed leaking due to the tank pressurizing. A new fully vented fuel tank cap is on the way, the measurements from the diagram are spot-on so hopefully it fits.

Click to expand...

The barb fitting is threaed to fit the drain screw threads. M5-.75. Some say you can get a plastic hose barb from the fish store that works well enough. Other folks just warm up the plastic tube and work it into the threads till it seals. I make the fittings from aluminum because I can.

Motörhead said:

https://www.motomentum.com/2fastmot...ome-fuel-tank-filler-cap-17620-402-010-139657

Click to expand...

Fuel cap fits, springy too.