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Main Area => General GS500 Discussion => Topic started by: Afzzr12 on March 12, 2007, 10:49:14 AM

Title: running way rich on stock jets
Post by: Afzzr12 on March 12, 2007, 10:49:14 AM
I have a strange problem.  My left side cylinder is super rich.  As far as I know the jets in the carb are stock, air filter is stock, and the exhaust is stock.  Th right cylinder is almost lean, but the left is super rich.  The plug is black and I am blowing out grayish colored smoke. 

I just cleaned, replaced float needles and all o-rings, and set float height.  I have the idle mixture screws turned out 2.75 turns on each.  I have tried leaning out the left, but I am still super rich all the way through the rpm range.  What might be happening.  The plug doesn't gas foul so I know it is burning it all, but I is just too much. 

Could it be a vacuum leak from the line running to the frame petcock?

Please help!!
Thanks
Alex
Title: Re: running way rich on stock jets
Post by: hmmmnz on March 12, 2007, 11:21:48 AM
is it sparking?? or back firing??
Title: Re: running way rich on stock jets
Post by: scratch on March 12, 2007, 02:06:59 PM
Could be a fuel leak through the frame petcock diaghram, or the choke plunger is leaking by.
Title: Re: running way rich on stock jets
Post by: Afzzr12 on March 12, 2007, 07:21:05 PM
yep got spark on both cylinders.  No its not backfiring.  But the plug is super black, but it is dry so all the fuel is burnig it is just WAY TOO much. 

I will check the choke plunger.  I guess the old wd40 aroun the seal and see if it does anything :dunno_white:? 

I'll check the frame petcock diaphram.  It pumps fuel really well ( I have clear fuel lines to see), but it could still be an issue.

Thanks for the help I'll post up on what happens maybe tomorrow.  I have to work on the good ol ZED too though so I can ride this weekend.
Title: Re: running way rich on stock jets
Post by: ducati_nolan on March 12, 2007, 10:30:50 PM
It might be oil fouled.
Title: Re: running way rich on stock jets
Post by: Afzzr12 on March 13, 2007, 07:07:24 PM
Well here is a pic of the left side plug.  Not pretty at all. 
(http://i145.photobucket.com/albums/r238/afalex1/DSCF0587.jpg)


I tried spraying wd40 around the choke piston seal and nothing happened, but that doesn' mean it isn't still a bad seal.  I put hose clamps around the petcock vacuum line and no difference in running.  The only thing I haven't done is pull the carbs and ensure all the jts are right.  I am the 3rd owner so who knows what might be in there that I overlooked because I don't know these carbs that well yet.  I also have not pulled apart the petcock to see if it has a bad diaphram or not.  But, I just don't see how that could cause such a rich problem. 

By the looks of it I don't think it is oil at all.  Oh and I take back what I said early.  It does backfire a lot, but, it is not a loud backfire like I was thinking.  It is more of a muffled pop at all RPMS.  Hope this helps.
Title: Re: running way rich on stock jets
Post by: trumpetguy on March 13, 2007, 09:10:35 PM
A petcock problem can be ruled out because it would not affect one cylinder only.  It has to be something else.
Title: Re: running way rich on stock jets
Post by: The Buddha on March 13, 2007, 10:13:13 PM
Left = petcock diahragm cos the vacuum line goes only to that carb. BTW clear fuel lines dont so squat for you here, you need a clear vacuum line.
Cool.
Srinath.
Title: Re: running way rich on stock jets
Post by: Afzzr12 on March 14, 2007, 09:37:17 AM
thanks for the info.  I guess I will order the diaphram and see what happens. 

Yeah, I thought about the fuel line vacuum line difference so I put actual vacuum line on the vacuum port, not the clear fuel line.

thanks again

this is giving me a huge headache.  I just want to get this thing together so I can ride it more than down my road and back. 


Alex
Title: Re: running way rich on stock jets
Post by: scratch on March 14, 2007, 03:19:17 PM
Pull the vacuum line and see if it's wet with gas inside; that's the way to be sure that gas is leaking past the diaphram down into the left carb.
Title: Re: running way rich on stock jets
Post by: Afzzr12 on March 14, 2007, 06:18:10 PM
nope noe  gas leaking, but I did plug the vacuum line and ran it and it stopped the burlbling and small backfires.  I pulled the spark plug and cleaned of a spot and stuck it back in to see what color it would be.  AFter I ran it with the cleaned off plug and closed off vacuum line it was actually LEAN, REALLY LEAN.  But, it would stall out and idle really low.

I adjusted the idle and it ran a little better, but it would still stall out around 3000-4000 RPMs.  I think it might be fuel starvation now, but everyone else seems to be fine with the petcock on prime.  I guess I'll just keep fighting it a eventually figure it out.  This fuel/vacuum line setup is the most retarded thing I have seen suzuki do yet.  I have a petcock for a '03 maybe I will try and mount that. It might work.