Carb work...forgot about the gas

[jcgss77]

Sooooo, I just got a new bike, and the previous owner went and let the air filter disintegrate, which means the air lines in the carbs got clogged with...gunk. So I got it all cleaned out, and I went and forgot about putting some gas into the carbs. I also installed a new fuel filter, and the deal is now bone-dry.

Is there an easy way to run gas through the system, so my battery doesn't go dead from cranking? I don't know how old it is, but it has been pretty good so far, but I don't want to chance it, as I am pretty much broke and when I moved into my new place, I ended up getting rid of a lot of my stuff, which includes many of my tools and gear for working on my bike.

I think I need an eyedropper to get the gas into the filter, but is there a trick to getting some down into the carbs without having to take the whole thing apart again? I am not in a big hurry, since I am still waiting for the new air filter to come in.

[DannoXYZ]

Apply at least 10-in.Hg vacuum to little petcock hose. This opens valve and drip fuel through filter into float bowls.

[Triple Jim]

Danno is right, except it doesn't take anywhere near that much vaccuum to open the petcock. A tube into your mouth and some moderate sucking will do it.

If it took ten inches, the petcock would close every time you opened the throttle all the way.

[jcgss77]

Originally Posted by DannoXYZ

Apply at least 10-in.Hg vacuum to little petcock hose. This opens valve and drip fuel through filter into float bowls.

Originally Posted by Triple Jim

Danno is right, except it doesn't take anywhere near that much vaccuum to open the petcock. A tube into your mouth and some moderate sucking will do it.

If it took ten inches, the petcock would close every time you opened the throttle all the way.

Thank you for the replies!

So, just apply a little lung pressure to the carb side of the fuel filter will bring some of it down? Am I hearing you correctly?

[Triple Jim]

No, a little sucking on the vacuum line to the petcock.

It's made to automatically turn on the flow of gasoline when it sees carb vacuum (engine running), and turn it off when you shut off the engine and the vacuum stops. Sucking a little on the vacuum line will make it think the engine is running and it will open.

[jcgss77]

Originally Posted by Triple Jim

No, a little sucking on the vacuum line to the petcock.

It's made to automatically turn on the flow of gasoline when it sees carb vacuum (engine running), and turn it off when you shut off the engine and the vacuum stops. Sucking a little on the vacuum line will make it think the engine is running and it will open.

Ok. And that should then start the pressure down to the fuel filter, and then it is (hopefully!) smooth sailing?

[Nextbesthing]

Originally Posted by Triple Jim

No, a little sucking on the vacuum line to the petcock.

It's made to automatically turn on the flow of gasoline when it sees carb vacuum (engine running), and turn it off when you shut off the engine and the vacuum stops. Sucking a little on the vacuum line will make it think the engine is running and it will open.

Damn you Bernoulli!

[THusker]

Leave the fuel line to the carb in place and apply suction to the port on the Petcock to open the valve.

[VaFish]

Originally Posted by Triple Jim

Danno is right, except it doesn't take anywhere near that much vaccuum to open the petcock. A tube into your mouth and some moderate sucking will do it.

If it took ten inches, the petcock would close every time you opened the throttle all the way.

That just sounds so dirty.

[ducatiman]

^ but doesn't have to be

[jcgss77]

Ok, so I went and picked up the new air filter today, and after putting everything back together, I tried the suction on the fuel line deal...and it in no way worked. So either I have a petcock that is going bad, or more likely I was just too worried about getting gas in my mouth, I just opened up the choke and cranked the bike, and as I was watching the new fuel filter, it filled up, then a couple cranks later it fired right up. Ran like a top, and before I could take it for a ride, I got a call where I needed to pick up my kids. So the first ride is going to have to wait, but we are running. Thanks so much everyone!

[Triple Jim]

For future reference, there is a fuel inlet fitting on the petcock, and a fuel outlet fitting. There is a third fitting for vacuum on it. That's the one you suck on. Unless the diaphragm in the petcock is ruptured, you can't get gasoline in your mouth from that fitting.

[DannoXYZ]

Yep, there’s TWO hoses exiting petcock. Bigger hose is fuel line, leave it alone. Smaller one is vacuum line to turn on fuel flow. Hook up a 2-Ft section of vacuum hose and suck on it.

[sarcaz]

The purpose of the PRI setting on the petcock is to fill up (prime) the carb after it’s bone dry. Set it to PRI for 15 seconds and then set it back to On. This shouldn’t require vacuum to operate.

[Triple Jim]

Originally Posted by sarcaz

The purpose of the PRI setting on the petcock is to fill up (prime) the carb after it’s bone dry. Set it to PRI for 15 seconds and then set it back to On. This shouldn’t require vacuum to operate.

Pregens don't have a prime position. The have off, on, and reserve. On and reserve both require vacuum to pass fuel.

[sarcaz]

Apologies, I assumed it was the same as mine (1986).

[Triple Jim]

Well, I learned something too then, because I didn't know the very early ones had prime too. My old H2 has a prime position, which is pretty handy since it's kick start only.