petcock question

[labbatom90]

today i experimented with my petcock. it ONLY runs on prime.

this weekend ill check all the connections to see if the vacuum hose is connected, if not, ill have to look to see if its the the actual petcock.

is that pretty much all i need to check?
it literally purrs when on prime. so i figure the engine and carbs are fine. any diagrams to see where the vacuum hose plugs into the carbs? i really dont know what im looking for as far as that goes. but i know where it should plug in to the petcock.

so yeah any input would be awesome.

i wont get to check it out til friday or saturday

THANKS!

[labbatom90]

really? no responses? haha

[JaxKat]

All I know is that PRIME is really BAD to run in... Something about fouling up your engine.

Needs to run in ON (Pointing Down) I think it is down.

Yes it is:

RESERVE to the front.
ON down.
PRIME to the rear.

[beherenow71]

Do you mean the bike only runs on prime or the fuel only flows? I assume you mean the bike only runs. Not really sure, but I would try a petcock rebuild kit. It doesn't cost a lot and its about the only thing you can do to a petcock that I know of. Of course, checking to make sure all your hoses are connected probably isn't a bad idea either.

[labbatom90]

yes i do know that it SHOULD run in the ON position. but it doesnt

it runs PERFECTLY in the PRIME position, but does not run at all in on ON or RESERVE. and as far as fouling the engine and everything, it has been running great.

so i figure its one of two things:

1. vacuum hose in not connected properly, or not connected at all.
2. petcock needs a rebuild.

so my main question: where does the vacuum hose hook up to the carbs/engine? i am failry certain that it is connected to the petcock, but will check this weekend. and it has a strong possibility of not being connected correctly. so any pictures/ descriptions/ diagrams of where it would go would be helpful

[RossW]

#4 carb I believe. It should be pretty obvious from the side of the bike. The easy way to check if you petcock is bad is to hook a hose up to the vacuum port and suck. One of three things will happen:

1. Gas will flow: you have a vacuum problem
2. Gas won't flow: you have a petcock problem
3. You get a mouthful of gas: you have a petcock and mouth problem

[labbatom90]

#4 carb I believe. It should be pretty obvious from the side of the bike. The easy way to check if you petcock is bad is to hook a hose up to the vacuum port and suck. One of three things will happen:

1. Gas will flow: you have a vacuum problem
2. Gas won't flow: you have a petcock problem
3. You get a mouthful of gas: you have a petcock and mouth problem

so what is the good thing out of those three? haha

ok first thing though i just remebered that when my bike wasnt starting a while ago, we found that something hissed and sucked in air on the RIGHT side. is that the vacuum??! we put a little hose over it and zip tied it shut haha. hmmm
(that didnt fix the starting problem, but it was an open hole that could suck things in.... ) i eventually found the choke and it started right up.... i know im a genius.. haha

fo you have a picture somewhere, tomorrow i will get one and either post it, or campare to yours

[Kreylyn]

Black hose coming off the left side of this pic is the petcock vacuum hose. It should be plugged onto the center backside of the petcock, the NON brass nipple.



Krey

[labbatom90]

thanks,

well seeing as how i most likely wont be pulling my carbs off to check, unless i HAVE to if it came down to it. so when the carbs are on the bike (a pre) will this be visible through the opening of the fairings on the right side of the bike?

and is the other thing on the right (in the pic), the idle adjuster or choke? cuz that would confirm my guess.

[Kreylyn]

Your looking at the engine side of the carbs... so sitting on the bike...

vacuum nipple on the carbs on the right side...

petcock on the left side...

idle adjustment on the left side...

You would not need to remove your carbs... at the most, just lift the tank a little to see what is routed underneath it. Vacuum crossing from the right side to the left side for the petcock.

Krey

[labbatom90]

ok yeah that is what i thought. I honestly dont think that there is a vacuum hose even hooked up to either, ill check it out though, thanks. if nothing is hooked up, will any rubber hose work, or should i shop around for a real hose. most likely, because it will get hot correct?

[labbatom90]

ok thanks everyone! i checked it out, there was no hose hooked up from the petcock to the vacuum, so i went out, bought one, and now the bike is working perfectly! on the correct setting! im ecstatic, my bike for the most part is running as good as i want it to. maybe my gas mileage will pick up and be normal.

thanky you!

[scottynoface]

There you go man.

It was that little blue thing wasnt it?

[labbatom90]

well yes. that is where the vacuum is. i had to buy a hose to connect it to the petcock. and that was it. i rode it like 60 miles since then and i will figure out my gas mileage, i think i was geting below 30 MPG. and its already looking up! haha. i just bought some rubber vacuum hose from Autozone. and that was it,

[scottynoface]

That's awesome man, is it starting up any easier for you now?