Fuel drip problems - on the right track?

[KEITH KRAUSE]

Your new Pingel should operate correctly. It's easy to check if you thought it was a leak source.
Your leak is something to do with the float valve or the float.
The factory float level acceptable range is from .90 to .98" .94 is right in the middle and allows for a little tuner error. If you use the same method to set all four, I doubt the leak is because of the level adjustment. And if the float operation appears smooth and the floats haven't been damaged, it's likely the float valve isn't sealing.
Only other thing I can mention regarding the floats is to look at the "bright spot" where the adjustable float tab contacts the float valve spring tip. Usually, the spot is just a little rub mark that's smooth. But sometimes the spot can wear enough (pit) to cause a new or replacement float valve to not seat correctly. The new float valve spring tip won't line up perfect like the old one and it can lead to a sealing problem. If pitted or you see/feel a slight bump or lip to the spot, just gently rub it out with emery cloth. Just rub any bump or lip smooth. Don't bother to rub out the whole spot.
If that's OK, I'd focus on the valve.
Did you buy new float valves? Are they aftermarket? These aftermarket valves are often made cheaply and I've had new ones leak upon the first leak test. I always suggest to the owner to buy genuine Mikuni valves but I know they're expensive. I just want you to know the cheaper valves don't always work. Also, if you're using used valves, they MUST stay with their valve seat. The seat and valve wear as a unit and leaks can occur if you mix the valves and seats up. Also, check the valve spring for good operation. Is there any slack in it? Hold it with the spring facing up. If you gently push it in 1/2 way (no more) and gently release it until it stops rising, can you still pull out a little more? If so, that's too much slack. Do the test by using your thumb nail upside down because if your skin is a little sticky, the spring pin may stick to you a little. Also, if used, check the valve tip for grooving. Too much grooving will cause a leak.
After all you say you've done, I have to believe it's the valve and/or the seat.

[rustybronco]

The fuel is coming out of the lowest nipple on the bottom of carb 2. Per your previous suggestions back in the summer, I've rebuilt the carbs with 4 new kits including the o-ring kit available from another member. All new jets, needles, gaskets, seats, etc. My ruler only does 64ths so I set it to just a skosh below 1". With the carbs upside down, tab just touching the needle and gasket removed I adjusted all 8 individual floats as above. I spent alot of time trying to get that just right.

Please take this in the context that i'm NO EXPERT and for discussion it's just what i do...
i adjust the floats so they're parallel on a flat surface then install and set float level.

hold the carbs at 90 degress with the floats hanging vertical and tilt them until the float is JUST setting on the needle plunger and then measure the float height.

I have not reconnected the airbox or most of the vent lines. However when I first started tracking this problem down, everything was connected and installed. Could an air leak really be the cause all this time?

i don't think so.

Update: I just took off all the rest of the bowls and No.1 floats are obviously higher than all the others. Also, checking my math, .94 = 60/64th's right?

yes.

1. I'm getting way too much fuel delivered. After going for a brief ride, No.2 carb drips at a rate of 1/sec. on the side stand and dumps a solid squirt of gas when on the center. I've ridden the bike and tested the petcock in all positions and found that on PRI I'll flood the bike out and get alot of gas dripping from No.2. While in the ON position, the bike will starve and die. While in RES, the bike runs great though No.2 will still drip.

when on the side stand it will effectively raise the overflow pipe height.

1. I see that you have replaced the needle and seats but the floats are the same one that were in the carbs?, did the # 2 float sit lower in the container of gas than the others?
2. did the o-ring for the seat get damaged allowing gas to by-pass the needle and seat?
3. with the carbs off the bike and on the bench in the position they are on the bike, hold the 1-2-3-4 floats closed (use tape to hold the floats up) put gas to the fuel line and see if the're is a leak past the seat allowing fuel to over fill the bowl..
4. remove the fuel supply and tape, with the floats hanging down and pushing the floats up do they seem to hang or catch on their way up to closing the needle valves? see Keith's response for checking the floats.
5. if it doesn't leak anywhere past the seat or through the needle and seat may i suggest you lower the floats 1-2mm more and see if this stops the flow of fuel? the floats may be floating lower on the fuel bowl than normal.
6. if you change float height you must do plug reads when done!!!!

the honda that i worked on about 2 months ago i had to lower 3mm from the factory spec.(spec's 21mm and i had to set them at 24mm) they were at 25mm when i got it but i could not get them to stop leaking at 21mm (both with the stock and replacement needle and seats) so who knows what may have been done to it at some other time. at 24 mm float level the bike ran great with no drivability issues or starting issues or fuel leaks.

[demark]

Maybe I missed it this earlier in the thread, and I apologize if this is too simplistic a question, but have you determined where exactly the fuel is leaking from? (I come from an IT background and you may be surprised how many IT issues come down to "Are you sure it's plugged in / powered on?")

You say it's #2, but did can you find out where exactly on #2 it is leaking? It could very well be some place far from the point at which it drips. Liquids can flow an awful long way along a surface before pooling into a drip.

Being able to say, with 100% confidence, where the fuel is exiting the body might go a long way toward figuring what's wrong.

Example: A minute crack in the fuel line causes gas to flow down the body and drip from the bottom - you could spend weeks ripping apart the carb and not find the issue.

Thanks,
- Tony

[Sandy]

I just read most of this post and it's very possible this is the fix for your problem. Scroll down a bit for the fix. It's been 1 1/2 years since the repair and the carbs are still totally dry.

http://www.thegsresources.com/_forum/showthread.php?t=79717&highlight=carb+o-rings

[Pearson]

Prize goes to Rusty Bronco

First off a big THANK YOU!! to all who helped me but Rusty Bronco wins the prize. He suggested I take the bowl off and fill with water and when I did I observed no dripping from the bowl. But my neighbor just came over and in looking REALLY close at the pipe there's a hair line fracture running the length of it. You could hear it when he dragged his nail across it and frankly, I'm early 40's and my vision is going . When we filled it with gas...the dripping was almost immediate. His comment to me was that gas will go where water won't. I don't know how true that is (and I'm so happy I really don't know that I care!) but I'll just assume I did a poor water check, kinda like what Demark was saying.

Do I feel like a dummy? You bet, he found it in less than 5 minutes. I'm in IT too Demark and agree with you and sometimes you need a second set of eyes.

Now off to find a bowl for No.2

[rustybronco]

Clean and solder the crack...