#2 Cylinder is ****ing fuel out of the exhaust pipe

[Guest]

I recently acquired an 82 650l through trade and it started and ran ok when I picked it up just a few days ago. The man I bought it from said it had sat in the garage for about 3 years and he claimed to have never messed with the carbs because he was "afraid" of messing with them. I have not had time to clean the carbs yet, which I know it needs, but the number 2 cylinder is spitting quite a bit of gas out of the header(maybe the carb is flooding the cylinder or the valve isn't seating all the way?). I will be removing and cleaning the carbs hopefully this weekend, my question is, is there another reason that the gas is coming out of the header like that its obviously not firing there so I will check the plug and wire I know the coil is good since #3 and 4 cylinder are firing ok. Any input will be appreciated thank you

[Steve]

I'm almost afraid to ask, but how do you know it's #2 in the header?

Any decent exhaust system on a GS will have multiple pipes coming together, so it's hard to isolate one pipe.

I sorta get the impression that you have straight, cut-off pipes.

Please tell us that you are not running straight pipes.

But, to answer your question: You probably have a bad diaphragm in the petcock. The vacuum line that is supposed to open the petcock is sucking fuel through the leak and dumping it directly into the intake tract of #2, bypassing the carb entirely.

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[JTGS850GL]

The #2 carb is also the carb that provides vacuum to open the petcock. If the diaphragm in the petcock is ruptured or leaking it will introduce fuel into that vacuum line. That would cause a very rich condition on that cylinder.

[JOE91]

I'm almost afraid to ask, but how do you know it's #2 in the header?

Any decent exhaust system on a GS will have multiple pipes coming together, so it's hard to isolate one pipe.

I sorta get the impression that you have straight, cut-off pipes.

Please tell us that you are not running straight pipes.

But, to answer your question: You probably have a bad diaphragm in the petcock. The vacuum line that is supposed to open the petcock is sucking fuel through the leak and dumping it directly into the intake tract of #2, bypassing the carb entirely.

.

As I said I just acquired the bike a few days ago, and yes the previous owner has open headers pointing straight to the ground so I was positive it was the #2, I will put an exhaust on it when I can afford one. the current exhaust wasn't just cut down to the header its just bent pipe that's only got one bolt on each flange, it was certainly a hack job but the guy told me he didn't know anything about bike carbs so he never did anything to them. Overall the bike doesn't look in too bad of condition its just a little rough but the carb and exhaust are not in good shape for sure #1 has fire but not enough fuel.

I will start working on the carbs first and check the petcock as well hopefully its not in too much shamble when I open everything up wish me luck

[JOE91]

This is the bike when I picked it up, and that tail piece I think he said he got off of a kz1000 and bolted it to the rear
gs pic.jpg

[JTGS850GL]

While the carbs are off for rebuild, do the valves. Adjusting the valves must be done before the carbs are synced. Look at my sig and you'll find the GSResources greeting. Inside there are links to much good information. Here is the link to the CV carb rebuild tutorial. Visit the Bikecliff website and you'll find even more links to thinks like a factor service manual and wiring diagrams. Some of the links on the greeting post are broken but the Bikecliff site is working well.

[JOE91]

While the carbs are off for rebuild, do the valves. Adjusting the valves must be done before the carbs are synced. Look at my sig and you'll find the GSResources greeting. Inside there are links to much good information. Here is the link to the CV carb rebuild tutorial. Visit the Bikecliff website and you'll find even more links to thinks like a factor service manual and wiring diagrams. Some of the links on the greeting post are broken but the Bikecliff site is working well.

Thank you I used bikecliffs site for my 1100 manual and I've never done a valve adjustment before but I cant assume it would be that hard, as I am pretty fair with my mechanical skill and I learn fast I will check it out.