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FlyBorchetti
30th March 2005, 22:59
Anyone experience a problem with their petcock vacuum diaphram?

Here's the reason I'm asking:
First time on my bike for a while. In the morning it started right up and ran great. After work it started right up - no problems. While I was putting on my helmet and gloves it just died, like it ran out of gas. Tried to restart it and it just cranked but wouldn't turn over. Started wearing down the battery. Got a jump - still cranked but wouldn't turn over. Pulled the plugs - OK. Checked battery cables - OK. The choke cable seemed to be working properly. Took off the aircleaner and tried to start again. Didn't notice any gas smell and didn't see gas spraying from the carb.

Sure sounds like a fuel issue. Oh well, it's still under warranty so I'm taking it in tomorrow. Sucks though - it's 70 here today. i hate to miss a good riding day. :cry1
Just wanted to get your opinions
Cheers,
Fly
'04 1200C

Shu
30th March 2005, 23:14
You can check it with a simple MightVac pump.

Some thing you may want to try: Flip it over to Reserve and crank on it for a minute. Check to make sure the vacuum line is hooked up to the intake and to the petcock. Then try the mightyvac and see if you can get fuel to flow with about 5 lbs of vacuum.

OR take it to the dealer and let them check it out.

LuxBlue
31st March 2005, 16:31
Are you sure it wasn't this problem?

http://www.xlforum.net/forums/showthread.php?t=4869

FlyBorchetti
31st March 2005, 16:35
No, it wasn't out in the rain and it didn't tip over. I'm stumped.

BonRu
31st March 2005, 16:44
Same thing happened to me. 5 Harley mechanics couldn't figure it out in 4 days. They tried everything. Turns out, it was some stuff in the gas (very tiny particles like sand) catching in the diaphram. They cleaned it out and it ran great. Ran great a couple of days after that, and then when pulling up to a light; just died. Couldn't get it to crank to save my life. The guys pulled the tank, the petcock valve, the diaphram, etc., and cleaned everything. Put it all back together, and have never had the problem since. Took approximately 1.5 hours, on the side of the road, to get me running again. Turns out the mechanics at the shop never emptied and rinsed the fuel tank. Might be worth a looksee. By the way, the crap in the gas tank was from it sitting up and not being ridden in a while. Go figure. :rolleyes:

LuxBlue
31st March 2005, 18:08
The glitch I experienced was like a total electrical failure, probably attributed to the BAS (bank angle sensor). When it glitches you aren't in a tipped position. If you turn the key switch off and back on it resets. Happened to more than a couple of people here on the forum looks like. This fuel diaphram problem is new to me. My bike hat 4300 miles on it when it died. When it did, it shut down instantly, would crank but not start till I cycled the key switch. If it happens again though I'll be sure to check the fuel diaphram.....is it inside the tank??

GWR
31st March 2005, 19:19
When that happened to my 04, the engine spit back when it was cold and it blew off the vacuum line for the fuel shut off, once it was connected again by the dealer, one trailer ride and 2 days later, it worked just fine.

FlyBorchetti
1st April 2005, 16:22
GWR:

Exactly what happened to me. There was the vacuum hose dangling underneath the petcock. I plugged it back in and it fired right up. Rode it in this morning and it ran great. Too bad I didn't see it the other night when I was stranded. It was too dark. Time to put a pen light in my tool bag. Man I felt like an idiot.. oh well, live and learn.

Cheers,
Fly

BonRu
1st April 2005, 17:22
GWR:

Exactly what happened to me. There was the vacuum hose dangling underneath the petcock. I plugged it back in and it fired right up. Rode it in this morning and it ran great. Too bad I didn't see it the other night when I was stranded. It was too dark. Time to put a pen light in my tool bag. Man I felt like an idiot.. oh well, live and learn.

Cheers,
Fly


Phew!!!! That makes it a lot easier to swallow! Glad you're back up and running in time for the weekend! :clap :clap

freakyt
1st April 2005, 17:39
I think next winter I'm going to take off that Vacum petcock and put a Pingel on there. I just don't like that vacum on there, it's one more thing to go wrong and strand you somewhere.

skooter
1st April 2005, 18:28
I've had some of my friends play a trick on me by pulling of the vacuum line to my petcock to see how long it would take me to figure it out. :laugh Check the hose and look for any kinks too. I have been toying with the idea of replacing it with an after market one that doesn't have the diaphram before this thing causes me trouble in the middle of the night on a lonely road somewhere. You might want to consider this as well. A simple rubber diaphram could cost you a tow someday.

FlyBorchetti
1st April 2005, 19:56
I'm down with that. Looking for Pingel next.

Have a great weekend everyone.
Cheers,
Fly

thunderpaw
1st April 2005, 23:57
I am with you for dumping the vacuum petcock. No trouble...yet. At least the one I had on my old Suzuki had a 'prime' position which bypassed the diaphragm in case it acted up. My stock petcock works fine, but I see it as a stranding waiting to happen. I like the looks of the Golan petcocks-and the fact that 'rebuilding' them only involves one 5/8 inch 'o'ring.

Kim

Bill2
2nd April 2005, 06:39
I kinda like the newer style vacuum petcock, you don't have to remember to turn the gas off every time you stop the bike! Forget on the old style and i seen them back gas up into the carb and down the cylinders on some motors. Not very nice to have a crankcase filled with gas mixed with your oil!

thunderpaw
2nd April 2005, 13:09
Yes, you can always forget...
I make it part of my shut down ritual...kill switch, ignition key, petcock, jiffy stand.
'course, it's kinda like wipin' yer butt...you only forget to do it once! ;)

Kim

Chip
3rd April 2005, 04:12
I'm with Kim, same shutdown sequence.