79 GL1000 - bad gas, impossible to idle now.

[Tal]

I suspect that it's time to rebuild my carbs.

I let the bike run out of gas while warming up, apparently. Killed the battery trying to start it, and killed it D.E.D. dead. It wouldn't take a charge afterwards, so I replaced it. Still no start, so I checked the fuel in the tank. Nothing came out when I popped it on reserve, even after pulling the petcock. Sure enough, I've got enough rust suspended in the remaining fuel to make it tough to siphon out, even.

After getting the tank drained and dried out, I put a fresh fuel filter in place, clean gas, and got 'er running. She no longer idles worth a darn - I mostly have to use the throttle lock to keep her up around 1300 or so to keep her running. Up over 3k, she runs great. From what I'm reading, it sounds to me like one of the low idle circuits must be plugged from the rust - time to rebuild the carbs?

It's gonna be a few weeks before I have the time to sit down and do this justice, and I don't want to do it over several days with breaks in between so that I lose parts or forget where they came out of. I think I'll be getting Randakk's kit and video and doing the rebuild when I can. Am I risking damaging it further by riding in the meantime?

[olchris]

IMO you should be OK "riding it"... it might stop/stall, and might be a PITA but just do it if you want too..... You might even move the crud within the carb galleries...

[robin1731]

If there is that much rust the filter could be at least partially plugged. Even the small filters above the fuel valve in each carb could be partially plugged. This will cause the bike to be low on power and make it run lean. Because it will be starving for fuel.

[scootsx2]

After you clean and rebuild your carbs and and before you reinstall them, you should do a very thorough fuel tank cleaning as well as thoroughly flush out the hoses, petcock and fuel pump and install another fresh fuel filter.

[Tal]

Thanks for the responses. It's really nice to have a place to come and confirm that I'm on a reasonable track with fixing whatever issues crop up - even if most of the time that's been "search, read something similar, and go fix it".

It's possible that it's running lean, but I don't really think so - above 3K I have all the power I could want; it's just at a proper idle that I've got issues. Setting it to about 1500 (by the bike tach, which is not what I'll use when I'm adjusting the carbs back to 'right') is enough to keep her running without much fiddling almost all of the time right now.

Is it possible to get to those filters above the fuel valves without pulling the carbs and doing enough disassembly that I should just rebuild them?

Yeah, I plan on pulling the tank and petcock and giving it a thorough cleaning when I do the carbs. I also plan to replace the filter with one of Randakk's, clean and then test the pump, and probably replace the fuel lines so that I know my entire supply is clean.

[robin1731]

snip................
Is it possible to get to those filters above the fuel valves without pulling the carbs and doing enough disassembly that I should just rebuild them?

No, but not that hard. Just pull the carbs and remove the bowls. Then take the floats off and the tab that hold the float valve assembly.

[Tal]

That doesn't sound too bad. Are there any gaskets that I'd have to replace to just go that far in?

[NCScooter]

Depends on how old they are, what happens when you pull the flat valve seats. When you get the Randakk kit, get his fuel filter too. It's cleanable and SHINY.

[GL1-242]

The local old bike shop here said today that they changed there gas formula again and most older bikes are affected. Having issue's with idle and running smooth at idle.

Paul

[Tal]

I rode about 350 miles this weekend, virtually all interstate. Before I left I set the idle higher so that the bike would keep running without having to play with the throttle at idle.

4 times this weekend I set the idle lower again, and now I think it's pretty close to the original setting for the bike. According to the on-bike tach, I'm now idling smoothly at about 950; a needle or so under 1k. Perhaps I blew out whatever trash; not sure.

I'm putting the carb rebuild on the deferred maintenance list for now, but am definitely getting Randakk's filter sooner and as soon as I have the time to take the back end of the bike apart will be pulling the tank to clean it. Probably take it to a radiator place like at least one of the posts on the matter recommends on this forum.

Thanks for the advice! I'm certainly not assuming that it's all splendid now; just that it runs well but has an issue that I will have to correct when I get the opportunity.