Really Need Help Again - Carbs - Please!

[Anonymous]

Okay guys, I really need some help on this one. It's my 1981 GS550L Rebuild again.

Here's what I've done: 1)Cleaned carbs as per carb cleanup series. 2)Installed set of points. 3)Checked petcock for operation - releases gas when I suck on the vaccuum line, shuts off as soon as I release my tongue, gives vaccuum on my tongue. 4)Set timing as per Earl's error free method. 5)New plugs with white/blue spark on all four.

Here's the Problem(s): 1)No power between 3000 & 5000 rpm, with very slow acceleration below 5000rpm. 2)Plug #'s 3&4 are completely fouled with black soot after about ten minutes of running. 3)Bike drained almost full tank of gas through breather drain hose in one night.

If anyone has even a partial definitive answer please respond.

[Billy Ricks]

Float level(s) are either set too high or you have a sticking float needle. Make sure the fuel level is set to the correct heighth in the bowls and that you don't have a worn out float needle(s).

[SqDancerLynn1]

Very frustrating If gas drained from the tank overnight IT HAS TO have a problem with the fuel valve on the tank. It also has a bad needle or float sticking in at least one of the carbs possibably # 3&4 acording to your post, If they are flooding the plugs would be black and sooty.I would double check the float level If that is ok? (If you can afford it) I would replace needle and seat assembly in carb 3&4 CHECK that there is no gas in the oil

[Anonymous]

I agree there is no way you could drain the tank if the vacuum petcock was really working. You sure you didn't accidently switch it to PRIME? This setting, and float(s) that were not shutting themselves off, or bad o-rings around the float needle seat would allow for a bad rich setting -- plus if one float is set way too high, or is not shutting off could allow fuel to transfer to the other carb via the vent tube tee that goes between them, so it may still be only one carb that is the culprit.

Come-on, join the "I've pulled my carbs off ten times to get it right" club. Membership is free!

:roll:

Roger

[Anonymous]

Hey thanks guys.

Roger, I followed a method you gave from a previous post as to how to check the petcock, and I'm 100% sure that I have the float height correct. I'm going to rip the carbs off again today and check the seat, needle and o-ring on numbers 3&4. When I also took the petcock out to look at the diaphragm and it looked like new. Where can I get a rebuild kit for the petcock? (or an aftermarket?)

Thanks Again,
Craig

[earlfor]

Craig

I had an intermittant leaking problem with my stock petcock and it looked and seemed perfect. I finally gave up messing with it and replaced it with a Pingel. The Pingel isnt vacum operated, so when its in the on position, fuel flows. The negative side is you have to turn the fuel to off whenever you shut the engine down. The big plus is no more worry about finding gas in your crankcase oil.

Earl

Hey thanks guys.

Roger, I followed a method you gave from a previous post as to how to check the petcock, and I'm 100% sure that I have the float height correct. I'm going to rip the carbs off again today and check the seat, needle and o-ring on numbers 3&4. When I also took the petcock out to look at the diaphragm and it looked like new. Where can I get a rebuild kit for the petcock? (or an aftermarket?)

Thanks Again,
Craig