Putting back my carbs and gas tank and unsure... help?

[mr72]

Nope. Those are the "intake boots" in normal parlance.

The rubber diaphragms are under the top black plastic covers on the carbs. They are the thing that actually pulls the slides (and needles) up allowing air and fuel into the engine.

[tzzzel]

Hey guys. Me again, OP. Just spent about another 2.5 hours today with the same result. I even cleaned out the main pilot (the small hole one) with threads from electric wire, but still the same issue: idles at 2k rpm w/ choke, w/o choke drops to 1k, then dies. Throttle responds a bit before dying. Frustrating because I've cleaned carbs since I was 19 and never had an issue like this.

Here's what I see so far, based on my actions and your comments:

1) Maybe the rubber diaphragm was damaged by carb cleaner? I sprayed every orifice. If that's the case, what do I do? Buy a new carburetor?

2) Maybe there is more gunk in the main needle than I thought? Even though I cleared the hole, the gunk might still be around the hole. If so, how can I best clean this... carb cleaner swimming pool?

3) Maybe my idle screw (the big knob) was accidentally pushed around during installation? How can I check if it's the right turn?

[qcbaker]

Hey guys. Me again, OP. Just spent about another 2.5 hours today with the same result. I even cleaned out the main pilot (the small hole one) with threads from electric wire, but still the same issue: idles at 2k rpm w/ choke, w/o choke drops to 1k, then dies. Throttle responds a bit before dying. Frustrating because I've cleaned carbs since I was 19 and never had an issue like this.

Here's what I see so far, based on my actions and your comments:

1) Maybe the rubber diaphragm was damaged by carb cleaner? I sprayed every orifice. If that's the case, what do I do? Buy a new carburetor?

2) Maybe there is more gunk in the main needle than I thought? Even though I cleared the hole, the gunk might still be around the hole. If so, how can I best clean this... carb cleaner swimming pool?

3) Maybe my idle screw (the big knob) was accidentally pushed around during installation? How can I check if it's the right turn?

#1 seems most likely (to me at least). And if that's the case, you can buy a replacement diaphragm set: http://www.partzilla.com/parts/detail/suzuki/SP-13507-17C01.html

[mr72]

The diaphragms are probably damaged. If you sprayed carb cleaner into the carbs with the diaphragms in place it's virtually guaranteed they will get damaged. No point in doing any more investigation until you confirm that they are intact. The once you fix it, stop spraying carb cleaner into or on the carbs. It will also ruin o rings.

[tzzzel]

Oh, thanks. Cause I am totally out of ideas after this 3rd carb clean.

I never did do a good read up on how to use carb cleaner. For future reference, I guess I should just take out the jets and clean them individually? And if I did need to clean out orifices in the carb, I should remove all the wires attaching to it and remove all rubber?

[mr72]

http://www.gstwin.com/carb_work.htm

That's kind of hard to beat and incidentally the first non-YouTube link brought up by a Google search on "clean GS500 carburetors".

Step 1. disassemble the carbs to remove all rubber and plastic parts
Step 2. clean...

If you skip step 1 not only can you not clean it adequately but you also ruin a lot of the parts you should have removed because the solvents in carb cleaner will readily dissolve some of those rubber parts.

[tzzzel]

Update: I'm still getting a main jet clogged.

Thanks for the tips. It's been rainy and I've only today got to replacing the diaphragms. The old ones looked fine, actually. But I'm almost 95% sure it's because I keep getting my main jet clogged. Keep in mind, this wasn't really an issue the years before I let this bike sit. But when I open up the carbs I see all this coca-cola colored gas coming out... and I believe there might be particles or hardened stuff in my tank. I say this because I did everything right, and I also cleaned our my main jet, one of which was clogged completely. When I started up, everything was normal for about 10 seconds! I could hear the RPM being at the right note for 4.3k ish RPM. But then after that, I hear it chug and die down to 1k+ with choke... and I realized that the main jet probably is clogged again.

So, what should I do at this point? Should I get my tank completely cleaned out by a pro? I tried inline filter, but it was odd because my hoses didn't match up and I had trouble finding space to fit it... but I'll gladly work with it if you guys recommend it. I have a feeling there still stuff in my gas tank, even with fresh gas now.

[mr72]

It's not using the main jet at idle. When cold and on choke it's using the fast warm-up jet. Most likely sticking float needles or low floats from the description.

Sounds like you need to clean the tank before you move on.

[J_Walker]

cleaning the gas tank is easy. no need for a pro. if you use a medium to break off the particles... use something magnetic like self tapping screws. also as long as your gas tank is empty of liquid and only has old crusty fuel left inside. it's okay after shaking the crap off the inside lose, using a shop vac to suck the powdery/flaky stuff out is better then rinsing it 10 times.

[tzzzel]

It's not using the main jet at idle. When cold and on choke it's using the fast warm-up jet. Most likely sticking float needles or low floats from the description.

Sounds like you need to clean the tank before you move on.

Hi sorry could you clarify the different jets? All in know is there are three : big hole medium hole, small hole and I assumed small hole was the main jet. Which is fast warm up?

[tzzzel]

cleaning the gas tank is easy. no need for a pro. if you use a medium to break off the particles... use something magnetic like self tapping screws. also as long as your gas tank is empty of liquid and only has old crusty fuel left inside. it's okay after shaking the crap off the inside lose, using a shop vac to suck the powdery/flaky stuff out is better then rinsing it 10 times.

Thanks. I don't have a shop vac, but I do have a gas container that I could put the gas in. No magnetics either. I honestly might take it to a local bike mechanic he probably has the tools. I don't. I just want to get this done. Totally sucks to keep getting clogged agina and again