Another dead on the roadside thread

[Greenagain]

I'm in the process of ressurecting a 1980 GS1100E.
I had just replaced the stock fuel tank with one from a 750E, and changed the fuel lines.


See the last post for an update and my recent issues.

[tkent02]

Usually the last thing you messed with is the culprit.

Is there gas getting into the carbs?

Is your fuel tank vent cloggged??? There is a vent in the gas cap.
Run it with the cap popped open, if it's fixed that's your trouble.

Could be a petcock thing too, clogged screen, vacuum diaphram not doing it's thing.

Is the vacuum line coming from the right place?

Assuming there is spark to the plugs? Not likely to fail the ignition after riding two miles or so...

[bonanzadave]

Usually the last thing you messed with is the culprit.

Is the vacuum line coming from the right place?

Yeap. Probably got a kink in your new petcock vac line. BTDT

Switch over to Pri. Any difference ?

[Shin-Ken 1074]

When set to Pri drop one of the carb bowl drain bolts to confirm fuel flow.

[Muser3]

dead one

Sure sounds like a clogged vent. Been there and done the whole routine. Runs well, then stops. A vacuum develops in the tank and the fuel cannot leave the tank.
Lee :-D

[Greenagain]

Sorry for the lame opener, with the lack of actual information. I guess I was just letting out my initial vent for being stranded for the first time in years. Waiting for tow trucks sucks.

Anyways when I get to investigate it further I hope I'll be able to add some relevant details.

Forgive my ****-poor internet forum manners.

[Greenagain]

Well when I took the gas cap off there was no sucking sound from any vacuum. Cranking with the cap off didn't help.
The fuel line leading to the carbs was pinched somewhat so I shortened it to alleviate that and tried again, but could still not seem to get fuel to the carbs.
I opened the drains off of 2 of the 4 carbs, and the one below the petcock had a small amount of rusty sludge on the top of the drain screw, but all the carbs were basically dry.
This is a new to me fuel tank. I removed it, and removed the petcock. I took the petcock apart, and the diaphram looks good- no rips or anything noticeable. The plunger moves freely. I tried spraying some brake cleaner in every different orifice to see if I could get it to flow one way or another but it doesn't. Hopefully I washed out anything that may have been blocking it.
I need to do something to this tank so it doesn't rust out before I try running it again. The gasoline that I poured out is rusty colored, and had some fine rusty sediment in it.

[renobruce]

to test the petcock, you need to suck on the vacuum line. If you have the room, put in an inline fuel filter until you get your tank sorted. You may also need to put the petcock on prime until the bowls are full.

[Greenagain]

Booo Hiss.

I wish I didn't have to bump this thread, but I'm still having trouble.
I removed my inline fuel filter yesterday, and filled my carb bowls by using a mity-vac on the vacuum line. The bike runs just fine around town, but today on the way to work while buzzing along the freeway at 75 mph or so for about 10 miles it managed to suck it's bowls dry, just like before. While on the side of the freeway I sucked on the vacuum line to draw fuel back into the bowls. Unfortunately I neglected to bring tools ( I thought I had the problem licked) so I couldn't lift the tank up to re-install the vacuum line to the carbs. I figured that if it wasnt' receiving enough vacuum to keep the bowls full, that the vacuum line wouldn't matter. I was wrong. It barely got 2 miles before dying. I re-loaded the bowls a 2nd time, and finally managed to get the line back on. This time I stayed under 70 mph, and made it the last 12 miles with no trouble.

What's my darned problem here?

[LarryA_Texas]

filter screen?

You said there was sediment in the tank. Have you tried to remove and clean the filter screens above the needle valves? At least look at them and see if they're a mess. You had gunk in the bottom of the float bowl. It came from somewhere. You didn't mention if running in prime makes any difference, but that would tell you something, too.