carb issues on an 80 xs1100s

[Seabass Critt]

I just got my bike running again after sitting for 13 years, but it didnt want to idle, so i took the carbs off and gave them a good cleaning, now that they are back on and everything was put back on the way they came off, it wont start, all 4 carbs are getting fuel on the bowls, i checked for spark and all 4 plugs are strong, and it has compression, these carbs run off of the engine vacuum i believe. What really gets me is that, even when I stray starting fluid there is nothing, did I miss something??

[BA80]

Fuel, compression, and fire should be all you need. You have to be missing at least one of those componants.

[Seabass Critt]

I have all, but something is now keeping the fuel and air from going into the cylinder, before I took the carbs off it ran but ran rough, the only things i took off were 2 fuel lines, and the throttle cable, all have been re-applied.

[BA80]

That doesn't make any sense. unless you had rags or something in the intake boots and forgot to take them out.

[Seabass Critt]

I didn't bother using rags, it was a nice day with little wind, i had everything done in an hour or so. unless something is stuck in a vacuum jet or something, these carbs were in rough shape when i took them apart. I guess I will have to take them off again and maybe carefully use compressed air or something to insure all the ports and jets are free of gunk.

[Seabass Critt]

another thing i am thinking may be giving me problems are the intake boots from the engine to the carbs, they all have cracks, but i dont know it they are all the way through or not...

[BA80]

I doubt the cracks are all the way through. Taking it apart and checking your work is a good idea.

If those carbs were as dirty as I think they were you need to disassemble them all the way, except for separating them, and clean them real well. Look HERE for some good instruction on how to proceed with that.

[Seabass Critt]

ok thanks, the only thing shown that I didnt take apart was the upper parts of the carb. for the lower i used seafoam spray for anything with rubber on it, and light sprays of non drying starting fluid on solid metal parts. ex. carb bowl, bolts, screws etc. i just didnt use compressed air because i didnt have air valve tip.

[BA80]

One thing I will add to rebuilding is unless a jet or emulsion tube is corroded, broken or otherwise damaged beyond use reuse them all. The kits that come with new ones are unfailingly wrong and cause a whole new set of problems.

I do suggest getting what's called a po' boy kit. It comes with a new float bowl gasket and float valve. That should be all the new parts you really need.

I don't see it mentioned in Kat's carb cleaning thread but one of the problems those later carbs has is that the seat for the float valve doesn't screw into the carb body like the earlier ones. It just pushes in and is held by that keeper and phillips screw you see in the pic.

There is a rubber o ring on that seat that seals it in it's bore and those o rings get old and harden and cause flooding. Be sure to replace all of those.

[Seabass Critt]

all of the copper/ brass parts i removed cleaned up nice and shiny, and nothing was broken so that is a plus, haha all the "O" rings i saw looked fine and nothing was dried out, but i will take another look.

[BA80]

I would replace those float valve o rings anyway. Hope you can afford it though because it'll probably set you back about $.97.

[Seabass Critt]

haha i dont know, thats kinda steep when i got the bike running and put fuel in it, gas kept over flowing in the carbs and it poured into the intake, after i took it apart i found that the floats were stuck so it just allowed gas to keep pouring it, now i can leave the fuel on and it doesnt do that anymore! ha

[motoman]

haha i dont know, thats kinda steep when i got the bike running and put fuel in it, gas kept over flowing in the carbs and it poured into the intake, after i took it apart i found that the floats were stuck so it just allowed gas to keep pouring it, now i can leave the fuel on and it doesnt do that anymore! ha

Be sure and change out that oil before firing it up.........

[Seabass Critt]

the guy i got it from changed the oil a month before i got it, the oil looks and smells fresh, thanks though!

[BA80]

Moto is worried that since you said the fuel was leaking into the intake that the oil may have become fuel contaminated as it could have leaked past the rings into the crankcase.