GS650 starts but dumps fuel.

[Krunk_Kracker]

OK well, the good news is, the GS is finally running, albeit barely, but it is still a step in the right direction.

It's a 1982 GS650GL

Here's the deal: It starts with full choke and with giving it a little throttle, with the petcock on "ON". It's a little work to keep it running, feathering the throttle a little until it will finally idle this way.

As soon as the choke is let off, even a little, it still runs as long as you work the throttle a bit, but then the carb starts dumping fuel. If you rev it, it bogs until about 2500rpm where it will rev up and sounds very clean and healthy.

I'll try to give as much info as possible: The petcock vacuum is connected with a new line. The carbs have cheap foam pods on them. The bike has just over 28K miles on it. We used fresh gas.

Any help and advice on this would be GREATLY appreciated and if you need any other information, I'll do my best to answer them!

Please help, I am iching so bad to get this thing on the road.

[tom203]

OK well, the good news is, the GS is finally running, albeit barely, but it is still a step in the right direction.
1982 GS650GL

Here's the deal: It starts with full choke and with giving it a little throttle, with the petcock on "ON". It's a little work to keep it running, feathering the throttle a little until it will finally idle this way.

As soon as the choke is let off, even a little, it still runs as long as you work the throttle a bit, but then the carb starts dumping fuel. If you rev it, it bogs until about 2500rpm where it will rev up and sounds very clean and healthy.

I'll try to give as much info as possible: The petcock vacuum is connected with a new line. The carbs have cheap foam pods on them. The bike has just over 28K miles on it. We used fresh gas.

If you're just getting it going again, I would check for correct petcock operation to rule out fuel delivery problems. I disconnect fuel and vacuum lines, rig up some hoses and test that it flows nicely in prime, but not in on or reserve unless you suck on vacuum line.
As for pods, since it sounds like bike arrived with them, unless you remove and dismantle carbs, you won't know if the carbs were rejetted to suit even cheap pods. The consensus here is to not use cheap pods anyways unless you like carb tuning research.

[Redman]

You say it dumps fuel after running a while. You didnt say it dumps fuel when sitting overnight or sitting for a few days... so I do not suspect a problem with the petcock. At least not the problem of the petcock not shuitting off.

THe other problem with the petcock could be that the diaphram in it is damaged such that the vacuum line that is suppose to just open the petcock is also sucking gas in to that one carburator. One way to test for that (if your petcock has a PRIme position, I dont know about GLs) would be to pull off the vacuum line to the petcock (and plug the line with bolt or golf tee or something) and put the petcock on PRIme (but dont leve it there for days) and run the bike and see if things are different.

You say it dumps fuel while running and after it does this and that (running poorly). So I suspect the reason it runns poorly is that one (or more) of the carbs is already overflowing, it just that it takes a while before it oveflows out where you can see it. And this oveflowing is related to something with the floats and the float needle/seat.

A couple things you can do to determine what carb it is:
- from a cold start, touch each exhaust pipe (with back of fingers) every few seconds to get a feel for how they are warming up. I suspoect you will find one that does not warm up as fast as the others, will be near burning yourself on some after about a minute while one is only barley warm.
- take off the air box so can see which carb is dripping ... oh, wait,, you said you have pod filters ... and you really didnt say were the gas was dripping from. When you say "dumping fuel", I took that to mean that gas was dripping out somewhere. Or do you just mean it was running way to rich?

Anyway, I suspect soemthing relative to your floats and or the float needle valves, such that the gas level in the float bowls is uncontrolled, and is oveflowing into the carbs and that is why it is running poorly and why have gas dripping after a while. <<I am not a big carb expert, but I have had this happen to me>>

Could be that have a worn float needle that will not seal well against its seat and can not shut off the gas flow.
Could be that is gunk in the around the flaot needle such that it doesnt move freely.
Could be that the float heoght adjustment is way off for some reason (you have carbs apart and dissasembled?)


.

[tkent02]

The easy way to get it running right is to clean the carburetors correctly, adjust the floats, and find the original airbox it came with... The hard way is to clean the carbs correctly, adjust the floats, buy decent pods (K&N) and mess with jetting all summer.
Did I mention you will need to clean the carbs and adjust the floats?

[Nessism]

Sorry if it seems like I'm being a jerk but please read this...http://www.thegsresources.com/_forum...d.php?t=171846

[Krunk_Kracker]

If you're just getting it going again, I would check for correct petcock operation to rule out fuel delivery problems. I disconnect fuel and vacuum lines, rig up some hoses and test that it flows nicely in prime, but not in on or reserve unless you suck on vacuum line.
As for pods, since it sounds like bike arrived with them, unless you remove and dismantle carbs, you won't know if the carbs were rejetted to suit even cheap pods. The consensus here is to not use cheap pods anyways unless you like carb tuning research.

OK, I'll take the tank offf and recheck that the petcock is flowing correctly. I checked it a few weeks ago and it was, but I will definitely do it again. The pods were on it when I received it, and I do not have the original airbox in good condition. Plus, I like the look of the pods and plan on replacing them with some nice K&N ones. I don't mind the tuning and rejetting, I look at it as a learning experience.

You say it dumps fuel after running a while. You didnt say it dumps fuel when sitting overnight or sitting for a few days... so I do not suspect a problem with the petcock. At least not the problem of the petcock not shuitting off.

THe other problem with the petcock could be that the diaphram in it is damaged such that the vacuum line that is suppose to just open the petcock is also sucking gas in to that one carburator. One way to test for that (if your petcock has a PRIme position, I dont know about GLs) would be to pull off the vacuum line to the petcock (and plug the line with bolt or golf tee or something) and put the petcock on PRIme (but dont leve it there for days) and run the bike and see if things are different.

You say it dumps fuel while running and after it does this and that (running poorly). So I suspect the reason it runns poorly is that one (or more) of the carbs is already overflowing, it just that it takes a while before it oveflows out where you can see it. And this oveflowing is related to something with the floats and the float needle/seat.

A couple things you can do to determine what carb it is:
- from a cold start, touch each exhaust pipe (with back of fingers) every few seconds to get a feel for how they are warming up. I suspoect you will find one that does not warm up as fast as the others, will be near burning yourself on some after about a minute while one is only barley warm.
- take off the air box so can see which carb is dripping ... oh, wait,, you said you have pod filters ... and you really didnt say were the gas was dripping from. When you say "dumping fuel", I took that to mean that gas was dripping out somewhere. Or do you just mean it was running way to rich?

Anyway, I suspect soemthing relative to your floats and or the float needle valves, such that the gas level in the float bowls is uncontrolled, and is oveflowing into the carbs and that is why it is running poorly and why have gas dripping after a while. <<I am not a big carb expert, but I have had this happen to me>>

Could be that have a worn float needle that will not seal well against its seat and can not shut off the gas flow.
Could be that is gunk in the around the flaot needle such that it doesnt move freely.
Could be that the float heoght adjustment is way off for some reason (you have carbs apart and dissasembled?)

The guy who owned it before me claims that he had the carbs rebuilt at a shop, he has no receipts saying so, but the carbs do look extremely clean and "newish". I think will take them apart and give them a good cleaning as well. The main problem here is, I am not all that familiar with carb tuning and really have no idea how to adjust the floats and needles, so I have a lot of reading and learning ahead of me.

I'm saying, it was almost 2am when I came in the house, and I was tired. It was dark and I did not have a working flashlight, but it looked as if the fuel was flowing from the left vent on the carburetor. I'm going to try and get some fuel line today and connect to those vents and run them under the bike...it's making a huge mess anyhow and it will make these easier to diagnose.

The easy way to get it running right is to clean the carburetors correctly, adjust the floats, and find the original airbox it came with... The hard way is to clean the carbs correctly, adjust the floats, buy decent pods (K&N) and mess with jetting all summer.
Did I mention you will need to clean the carbs and adjust the floats?

So, I think you're trying to say clean the carbs, adjust the floats? haha

I do not have the original air box, nor do I want to use it. I like the look of pods and look forward to learning how to rejet this thing and learning the carb all together. I just need to find some articles on rejetting and float adjustment.


I think what I am going to do...is go ahead and replace the petcock. It's a 30 year old bike, the petcock is hard to turn anyways, and it's not going to hurt it to have it replaced. After that is replaced, try it again and see how she runs. Then take the carbs off regardless and clean them up and adjust the floats and whatnot.


Thanks for all the help and please keep the ideas coming!

In case it helps, these are the pods that are on it currently.



Here's the bike in question.

[tom203]

Ok, lots of folks like the pod look- it's your call, but it's more demanding, so we're just warning you. From your pic of pods, I didn't see the two vent lines from the carbs - these use to run up over airbox- are they hidden or are my eyes getting worse?

[Krunk_Kracker]

Ok, lots of folks like the pod look- it's your call, but it's more demanding, so we're just warning you. From your pic of pods, I didn't see the two vent lines from the carbs - these use to run up over airbox- are they hidden or are my eyes getting worse?

No, there's no lines on them yet. I'm actually heading to the store very shortly to get some.

I'm willing to put the time in to adjust them, it will give me a good chance to get to learn the carbs better.

[JRossi17]

There pretty easy to take apart as long as all the parts are kept in one place. I thought it would be a lot harder then it was when i did mine.

No, there's no lines on them yet. I'm actually heading to the store very shortly to get some.

I'm willing to put the time in to adjust them, it will give me a good chance to get to learn the carbs better.

[Krunk_Kracker]

Sorry if it seems like I'm being a jerk but please read this...http://www.thegsresources.com/_forum...d.php?t=171846

I missed your post as we posted at the same time.

That is a very good break down and actually what my buddy and I have since decided to do. I'm getting a new petcock and the carbs are coming off sometime next week and we're going through them, I'm going to get all the orings and seals tomorrow. Although on that list, I'm definitely not the type to not listen to advice and I most definitely want to learn I detest the idea of taking it to a shop.

On to the progress. I went and got some fuel line and put it on the vents on the carbs and ran them down and below the frame.

We started it up with full choke - again it runs while playing with the throttle. If the choke is turned down, it starts leaking from the vents. As soon as the bike is turned off, it's starts leaking from the intake on the left most carb.

I'm thinking it is definitely that carb, but is someone able to tell me exactly what they think this may be, so I can know for future reference?

Thanks for all the advice!

[Flyboy]

Ok, here is my take on it.
The fact that you are willing to listen to good advice and learn your way around your bike means you are already half way there.
The folks on here have hundreds of thousands of hours working on GS motorcycles, and what they don't know is frankly, not worth knowing, stick with the advice offered and you will have that bike purring in no time.
Now, from what you describe, it sounds like you definatley have a flooding issue, probably a needle and seat/s that are not sealing, due to wear or crud stuck in there, or incorrect float levels.
The reason I say this is that the choke on these bikes is not a choke as you know it on a motor car that throttles the in coming air flow to richen the mixture.
It is in fact an enrichment system, that draws fuel into the motor, under normal circumstances if you open the throttle while the choke is applied, the bike will die, as you let in large amounts of air and this negates the rich mixture.
Now in your case, it will only run on choke if you apply throttle, thus letting in volumes of air, leaning it out.......see where this is going?
Also the fact that you can coax it through the low rev range and when you get the revs up high, it tends to clear and rev right through, this is because at high revs, the motor can now use and burn the excess fuel being delivered, where as at low rpm when the fuel demand is low, it can not cope with all the extra fuel and bogs down.
What to do?
Until you pull the carbs off, do a proper dip and clean, and reset the float levels, you are chasing your tail, and it is only going to lead to frustration.
Grab the step by step, with pictures, carb cleaning tutorial from Basscliff's site and get to it, that is your first step to GS bliss.

[Krunk_Kracker]

Thank you flyboy, I appreciate that input!

So, I've decided to dump the pods idea temporarily. Getting this thing on the road is priority. I am missing a few parts to the airbox I think. Mt, being a total GS noob, I did not realize that this part was part of the airbox, I thought it was a housing for wire, haha. Pic:



That's the part I have, what do I need to get to connect it to the carbs?

Also, can anyone tell me what carbs these are so I can order a rebuild kit for them? I'm at work and hoping to get the parts ordered asap.

[cowboyup3371]

Just go to www.cycleorings.com, put in your bike info and Mr. Barr (a member here) will send you the orings you'll need. Plus go pick up a can or Berryman's. After that, follow the directions on Basscliff's site to strip, dip, and put back together.

[Krunk_Kracker]

Just go to www.cycleorings.com, put in your bike info and Mr. Barr (a member here) will send you the orings you'll need. Plus go pick up a can or Berryman's. After that, follow the directions on Basscliff's site to strip, dip, and put back together.

Thank you! What is Berrymans?

Basscliffs site, I am discovering, will probably end up being my savior, haha.

What about gaskets for the carbs, or do I just need o-rings??


:EDIT: So this is the kit I need? http://www.cycleorings.com/#BS_Series_O-ring_Kit Please excuse all my dumb ass questions, haha, I really want to learn, but at the same time I don't want to waste time buying the wrong kits. I gotta get this bike on the road!

[Charlie G]

Thank you! What is Berrymans?

Basscliffs site, I am discovering, will probably end up being my savior, haha.

What about gaskets for the carbs, or do I just need o-rings??

It's carb cleaner/dip. Comes in one gallon cans with a parts screen. Leave parts in the can for 24 hrs.

cg