flooding/petcock issue

[kevsgs]

Yes, unfortunately I had already gone through the carb cleaning before I found this site, but I have read it and we did do everything except the changing of those o-rings, I'm really hoping that fixes the problem, old ones looked fine but when I went to one of the suggested web sites for o-rings there were a few sizes that were almost the same. So I just went ahead and ordered a new set from suzuki. With any luck tomorow she'll be leak free. Valves and needles are shiny and brand new, floats are fine and set to proper level, so this only leaves the o-rings. I'm keeping my fingers crossed.

[kevsgs]

I think I will also leave them sitting for hours this time, last time I got a bit excited when after a good 15 mins. and no leaks, put the bike back together and then got the flooding. lol. If nothing else I am learning patience from this project. I am feeling a little more confident about getting them to work with all the years of experience of you all. Thanks again for the help and suggestions I've recieved.

[kevsgs]

Temp fuel cell

Hey everyone, somewhere I read someone had converted like a radiator overflow as a temp fuel cell for bench testing. I tried doing something similar but got leaks where I tried to seal. What is the best epoxy for this?

[koolaid_kid]

Yes, I use a radiator overflow tank for my temporary fuel tank (I got the idea from bwringer). I went to AutoZone and bought the large one (they had two sizes). I use a 5/16" fuel line (don't tell Steve) secured with a zip tie to the tank. I use an in-line connector (also from AutoZone) to connect my tank to the exist fuel line on the carbs (the line on the carbs is also zip tied on). The tank had 3 nipples on it. I use the bottom one for the fuel line, the top one as a vent line, and left the other uncut. When I am not using it, I put the attached fuel line on the vent line so fumes won't escape. It also came with a cap, so you never have fuel exposed to the atmosphere while you are using it. Gasoline explosions, while they look good on cop shows, are detrimental to the garage in real life.
I'm not sure what you mean about leaks and epoxy, however. Mine has never leaked, and for a total investment of perhaps $15 it has provided a safe, capped solution to a temp fuel tank.
Did you start with something different?

[kevsgs]

Yea I started with something else, very poor setup, thats why I'm looking for a better idea, I'm not even going to say what I tried..lol. Your idea sounds great though, I'm heading down now to go get that setup, thanks.

[koolaid_kid]

Hey, like I said, I got the idea from bwringer. My setup/configuration might be a bit different (IDK), but he was the originator. It does work really well, though. I especially like having a cap on the tank. I have seen pics where folk are running their engines with an open container of gasoline connected, and it makes me shudder.

[silverhorse47]

Could you specify what you mean by "flooding" or "The float bowls just flood"?

Is your bike running? If so, is it running rich? Is fuel pouring out of the carbies? Is your air cleaner dirty?
S.

[kevsgs]

Hey, like I said, I got the idea from bwringer. My setup/configuration might be a bit different (IDK), but he was the originator. It does work really well, though. I especially like having a cap on the tank. I have seen pics where folk are running their engines with an open container of gasoline connected, and it makes me shudder.

That worked out awesome! Here's a pic:

[kevsgs]

Could you specify what you mean by "flooding" or "The float bowls just flood"?

Is your bike running? If so, is it running rich? Is fuel pouring out of the carbies? Is your air cleaner dirty?
S.

Well the fuel level rises above the floats and runs out of what I believe is the air ports for the mixture, the holes at the bottom facing towards the airbox. When the needles should be stopping the fuel as the float hits its hieght, they're not and it just floods/flows out of those holes.

[kevsgs]

And yes it runs, I don't run it very long because it overflows while idling, but if I stay on the throttle allowing the fuel to be used up it doesn't flood, and it sounds good. One reason I'm trying so hard to get it fixed is because of how strong the motor sounds while running.

[silverhorse47]

Thanks for the clarification. To me 'flooding' is raw gas in the combustion chamber, and 'overflowing' is gas running out of the vents of the carbs. Either way, this sounds like a mystery.

You said you can find a point in the float level adjustment where there is no leakage, but then at only .025" lower the carbs overflow? Is that right? It's hard to imagine how there could be a problem with the float needles or seats if they seal at some point in the adjustment. Could the floats be hanging up on the sides of the float bowls?

I was taught to 'spin' the float needles on the seats by hand, gently, a few times before finalizing installation, just to make sure the seat and needle were mated together properly, ...similar to how you might lap a valve. The idea isn't to grind away at either, but just to give the rubber or metal a chance to seat...especially if you have changed one without changing the other.

I hope new orings solve your problem. It sounds like you have been thorough, but do make sure the floats aren't rubbing on the sides of the fuel bowls. The sad truth is that on the bench the floats can be perfectly adjusted, but once the fuel is pushing up on them, all kinds of slop in the mechanism comes into play, and so you never really know (unless the bike runs like a clock) if the fuel levels are equal across the board.

A sight glass or clear tube attached to the fuel bowl drain plugs tells you exactly where your fuel is inside the bowl, and if your problem persists after you install the new orings...consider making one from an old drain plug. One would 'think' that if all the floats are set at the same level on the bench, that the fuel levels in the bowl would also be at the same level, but this is not always the case.

S.

[JEEPRUSTY]

The valves have spring loaded pins. Could these be weak and contributing to the problem?

The brass seats have an o-ring that may be weeping.
It seals the brass seat to body gap.
If it is seeping fuel it will not matter how new or good the needle valves are.

[BassCliff]

Hi,

Are you floats really floating? Or are they leaking, taking on fuel and not floating? Check the floats for damage, pin holes, cracks at the seams, etc.


Thank you for your indulgence,

BassCliff

[btbarb]

Well the fuel level rises above the floats and runs out of what I believe is the air ports for the mixture, the holes at the bottom facing towards the airbox. When the needles should be stopping the fuel as the float hits its hieght, they're not and it just floods/flows out of those holes.

(I'll start with I'm not an expert and I didn't sleep at a Holiday Inn last night.)

If you have new OEM needle valve assemblies that would seem to rule out bad parts, maybe there is something causing too much pressure on the needle valve assembly, the floats are engaging the valve incorrectly, or the floats aren't floating like BassCliff mentioned.

I think I've read here that if your temp tank is too high, that can create too much pressure on the needle valve assembly. Maybe someone else can answer if a clogged air passage in one of the carbs can create the wrong force somewhere else.

I just started learning, testing and messing with float levels and needle valve assemblies on two differnet sets of VM carbs. I check the float levels with the clear tube method out of the drain hole. On mine, I've noticed just very slight variations in how the tang on the float engages the needle valve can make a noticeable difference in the fuel level. How you bend, or how level each of the red lines in picture-A can affect exactly how the tang hits the valve needle. Also, picture-B show the tang itself with the red line, if bent slightly, it can affect the needle valve too. A little bit of change has a bigger affect than I originally imagined.

[kevsgs]

Made some progress

So the new O-rings came in. Got them installed and while in there just went through the jets to make sure they were nice and clean. I have previously checked the floats, that was actually one of our first thoughts but they function perfectly as far as floating, no holes at all. So with new O-rings in I set up for bench test. First try at .81", factory spec, I turned on the fuel and the bowls filled then the fuel stopped flowing. Now with this setup it would be like running on PRI. After about 15 mins they began to overflow just a bit, and I mean not much at all, a couple drops every few mins. Just out of curiosity I set them to .90", float height, with this it took 45 mins before it began to overflow, and it was the same, just a few drops over time. So I chalked it up to possibly running on PRI, so I set float height back to factory spec and put the carbs on the bike. This is where it got interesting. On PRI the carbs would overflow, but on ON they would not, this is with engine off. So with engine running, PRI would still overflow, but the ON position worked great. They were not overflowing, the bike ran for a few minutes with no problems to the point we were starting to adjust the idle and thinking we had finally got her going. Then it just stopped, like it was out of gas. Which is what started happening. I could fill the bowls with the PRI, then turn it to ON, and it would run fine but was just sucking the fuel out of the bowls and then die, the bowls for some reason were not filling anymore while it was in ON position. But for a good few minutes it was perfect. So I am momentarily stumped. Any ideas or suggestions?