Hi everyone

So I have this issue
(it can be read about here for anyone who feels ambitious) > https://www.hdforums.com/forum/sport...-and-dies.html

I'll keep it simple here though.

today I went through the process of removing my tank, I knew it had gas in it so I did the whole disconnect from the carb when the petcock is set to 'Off'.
A little gas drained out from the hose, but not much.
And so i got my container for the gas, and flipped the petcock to 'Res'
What came out was a trickle of fuel, so slow i turned it back to Off and rigged up a string to hold the container.
Then I was fiddling with the petcock while it was draining cause, well, it was taking forever!

So I disconnect the vacuum hose from the petcock (with way more force than I thought it would take by the way) and then fuel starts to move MUCH faster, it actually fills up the hose and empties the remaining fuel in the tank in a few seconds.

So my questions are
Could the petcock be clogged past the screen?

How would taking the vacuum line off affect this?

How is the vacuum pressure actually created? could it be a problem with the hoses?

I am thinking about getting a gravity fed rather than hooking this guy back up to my existing vacuum system without really knowing what happened
if i did this..
Would I still need the vacuum line on the Carb?


Thanks

 

the vacuum that is hooked up to the petcock actually turns the fuel on its a safety thing even with the petcock on the on position there should be no gas come out of it till you add some vacuum to the port

 

Plug the vacuum line to the carb and run gravity feed, less stuff to fail.

 

Right, okay, Thats how I thought it worked

So how come when I disconnected that vacuum, there was more flow?


My thoughts exactly.
Should I bother going online for one?
I saw this guy, a Vacuum Petcock By-Pass Kit
Or would it be a better idea to get a high flow petcock? or do dealers have decent prices on these?

 

Yes, what Scratt ( Hi ) says. I replaced my stock HD petcock, with the vacuum line, for a gravity feed Pingel - it works great. I took the vacuum line, doubled it over and put a tie wrap around the line choking it off. The carb is happy with the vacuum line plugged and the Pingel petcock drops the gas without the need of a vacuum.

 

Advance auto sells vacuum line plugs, or do what Artlee (Hey lol ) said, I just put a bolt with gasket sealer(make sure it's dry before you start the bike) on it in some vacuum line and put that on.

 

Thanks guys
What are your thoughts on this > http://crapmods.com/phpBB3/viewtopic.php?f=16&t=8954

But I am curious if I can somehow test my petcock without installing it in the tank and filling with gas and such?

I kind of want to do it the real cheap way, but if my petcock has some sort of other issue, then it still may not work... right?

 

That is a bad idea. You basically have a vacuum leak waiting to happen. A kink in a rubber hose will eventually crack. It's simple enough to just plug a vacuum line. Why would you want to kink it?

 

I've never tried that, the petcock I put on my Bud's bike was a 20 buck drag specialties. You could give it a try though, only cost time and not much. Try putting a piece of fuel line on the end of a funnel than attach it to the petcock and hold id upright, pour fuel in and see if it flows good or not. I would do this outside if I did do it.

 

The vacuum actuation is a safety feature for gravity feed systems. If you bypass it or do away with it, you should get in the habit of shutting the gas off when you're finished riding for the day. If not, an improperly seated needle valve can cause the cylinders and crankcase to completely flood with gasoline. I've seen it happen before (on more than one occasion), it is not all that uncommon. That's why they started putting vacuum actuators on fuel petcocks.