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[cywelchjr]

I found some yellow vinyl type hose made by Briggs and Stratton for lawn mower engines at my local hardware store. It has held up fine for over a year now.

Yep, that's the stuff I'm runnin. Works pretty good so far, we will see how it continues to go over time. I even put it on my lawnmower right before some creep took off with it.

[The Lorax]

when you do the "breadtie" sync, depending on how thick the bread tie is, you will need to asdjust the main idle screw out in order to return the rpm to a normal level. when it shot to 5k, it may have just been that the idle was set way too high from the bread tie. that said, fix the leaking carb first, no more fires please. have a nice day and ride safe

[Riddle]

the leak is still haunting me! cant figure it out.. does you guys think that placing the float in a bowl of water is a good way to test if it even floats? im startin to think that might be the problem. or maybe im measuring the hieght with the wrong tool. im using the mm side of a ruler... dude that sucks about your mower! i'd be bummed too

[WMarshy]

Have you tried this to make sure all floats are balanced with eachother? JAT Might be time for some new float valves and seats...

[DGXSER]

You probably have the older metal/brass floats. They have been known to leak before. I think I have read to put them in hot or boiling water to check for air bubbles.

[Riddle]

i did the bench test and it held the gas back so i think they are seating properly. but i dunno

[dbeardslee]

Are the little fiber washers in place underneath your fuel valves? I've heard of them leaking from there before. Teflon tape on the threads of the fuel valve will fix that one. Just trying to think of things that can leak there . Don's idea about a leaky float sounded pretty plausible too.

[Riddle]

ya the washers are in place. its a fast leak. its pretty much streaming out of the air vent and then dribbles out the air jet and the hole above that...

[dbeardslee]

There's only a few things that will make them overflow -crud in between the needle and the seat, worn fuel valves, incorrect float adjustment, leaking float, sticking float, or a plugged vent. Those are the only things I can think of.

Line filters between the tank and carbs is pretty much mandatory on these things. If it's not a problem with chunks of fuel line going downstream, it's rust from the tank, or chips of paint or old tank linings - always something.

If you want to see something interesting, pull the vent line that goes to the carbs that aren't leaking, put your finger over the end of it, turn on the gas, wait 10 to 20 seconds and watch what happens. It's going to look a lot like what you describe. Keep a rag handy .

[Riddle]

If you want to see something interesting, pull the vent line that goes to the carbs that aren't leaking, put your finger over the end of it, turn on the gas, wait 10 to 20 seconds and watch what happens. It's going to look a lot like what you describe. Keep a rag handy .[/QUOTE]


Haha I think I'll skip that one.

[dbeardslee]

Here's something for you to think about, as it relates to fuel valves. The 78/79 carbs use a metal tipped needle in a brass seat, so the fluid seal is metal to metal. It works fine as long as the needles don't get worn, which they do relatively quickly. The 80/81 carbs use a viton tipped needle in a brass seat. Instead of metal to metal, they have a rubber to metal seal which does a better job of shutting off the gas. They clip over the float tab, so not only will the floats close the valve, they'll open it too. They also last longer, and when they do fail you don't have to replace the needle and the seat - just the needle. I replace mine when I was having issues with overflowing carbs (hence my obsession with clogged vents ) with XV920 fuel valves, and their performance has been great. If you determine the fuel valves you've got need to go, it's something to think about.

And one final note - EVERY time I drain the bowls on my carbs, and let it sit without gas in them, I wind up with a stuck float or two when I first turn the gas on. A wrap with the back of a big screwdriver on the bowl and they come unstuck, and work great until I drain the bowls again. You also want to make sure your bowl gaskets aren't old and flattened out. I kept reusing mine, and applying a bit too much torque reattaching the bowls, so every time I would take the bowls off and reattach, the gaskets kept getting thinner and wider. They finally got wide enough to catch the sides of the floats, and that was an overflow party too.

[Ken Talbot]

Is there anything else that would cause the carb to overflow besides float or needle seat..

I've heard of this when someone with early model carbs connects the fuel line to the upper "T"s between the carbs instead of the lower "T"s.

[psycoreefer]

Hey, if you keep having problems with it shoot me a PM, I'm about 4 1/2 hours away but I'd be willing to come take a look and see if I can help you.