Vacuum petcock : V-Twin Forum: Harley Davidson Forums

VRSCR · 10-13-2009, 09:42 AM

I have a 2003 FLHT and it has died shortly after refueling 2 times. It dosent happen often. But I will refuel then within a couple miles it dies and will not restart. I get it towed to the shop and it fires right up. It has been severeal thousand miles since it happened again this past weekend. I get it towed home pull the air cleaner and twist the throttle. It squirts very little gas. The next twist nothing. I put my spark tester on the spark plug. Cranked the motor over and had spark. Then removed the spark checker, twisted the throttle and there was fuel being squirted in to the carb. I then turn on the bike and cranked it over. It started and ran fine.
It sounds to me like the vacuum petcock is not working properly. What are your opinions?

Nahanhoku · 10-13-2009, 11:17 AM

Petcock would be a good starting point.
It could be crap in your gas tank blocking the petcock. As you say it happens after you refuel, refueling may stir up something in your tank blocking the petcock fuel flow until the crap settles in the tank again.

TXCHOP · 10-13-2009, 12:37 PM

Quote:

Originally Posted by Nahanhoku

Petcock would be a good starting point.
It could be crap in your gas tank blocking the petcock. As you say it happens after you refuel, refueling may stir up something in your tank blocking the petcock fuel flow until the crap settles in the tank again.

Yup, could be the petcock. Also, could be the vacuum line to it. I would look at both closely. May even try to test with a mighty vac and see how it flows on with just a hose going into a can.You can repair the petcock it thats the problem or replace obviosly. If not, may have to check the carb for dirt etc..sometimes floats can get stuck and not move properly.

mator57 · 11-08-2009, 02:55 AM

i have had problems with th vent on th gas caps not workn.ride th bike and th next time it happens, loosen th cap and if it sputters then picks up and tunes out, replace th cap. just a thought.

Geezer-Glide · 11-08-2009, 07:34 AM

Like TXCHOP suggested, it's the vacuum line. They get old and soft from all the engine heat, then they collapse. When you let the bike sit, they expand and gas flows again. They cost 5 bucks to replace.

y2k-fxst · 11-12-2009, 08:16 PM

I just replaced my vacume petcock on my 2000 FXST last night with a Pingel. While draining the tank the gas would flow a full stream, then go down to a dribble. Just as I thought it was empty it would come back to a full stream. It did this all the way through the gallon and a half that was in the tank. When I pulled the petcock out the mesh "filter" in the tank was covered in black "sludge" (I figure it was probably sealer from inside the stock tank). The "filter" was plugged to the point that it was partially collapsed.