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So many carb issues and questions

571 Views 28 Replies 6 Participants Last post by  Beaker
Hello everyone! It as been so long! My bike has been sitting for about 2.5 years. Its pretty much a stock '03. It turns over and will start when I spray starter fluid in the air box. So I figured I needed to clean the carbs. The outside of the carbs looked terrible. I bought an ultrasonic parts cleaner and put it in there for about 15 minutes. Disassembly was pretty easy. I don't remember which carb it was but one was fine. The other had a gross white, grainy looking substance all over the top of the coaster enricher/air cut off valve. The space between the diaphragm and the cover was full of this stuff. On that same carb, the vacuum valve diaphragm had some hard deposits around the seal, on the underside. I soaked both of those diaphragms in simple green overnight. They both cleaned up well. I ended up using a 4:1 muriatic acid to water mixture to clean up the outside of the carbs once I had all the rubber and plastic off. It worked really well. Then I put everything back in the ultrasonic cleaner to neutralize the acid and to clean out all the little bits and pieces after I sprayed them all really well with carb cleaner. I did run in to one issue. The idle screw/pilot air screw on my carb is all the way in. I know my bike runs lean. Now I know why. Unfortunately, I cant get either of them out. And to make it worse, I just snapped off one side of the head. so...

1. How do I get the air screws out now that I only have half of a slot head left on them?
2. Less important, what was that crap all over the air cut off valve?
3. Once I get the carbs back on, I guess I need to sync them, right?
4. Anything else I should do while I'm here?
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I've got an airbox in one piece.

The chips broken at the end of the holes shouldn't hurt anything, as long as the screw doesn't leak.
Hey Sockster, I'll send you a message about your air box. "in one piece" is definitely a better status than mine! Fingers crossed those dang screws don't leak.馃I guess I'll be asking around for carbs if they do.
Hey Sockster, I'll send you a message about your air box. "in one piece" is definitely a better status than mine! Fingers crossed those dang screws don't leak.馃I guess I'll be asking around for carbs if they do.
How far are you from Lancaster county PA? There's a basket case I posted earlier.

I don't think the screws will leak, like you said they're recessed. They had space for a cap they pressed in there.
How far are you from Lancaster county PA? There's a basket case I posted earlier.

I don't think the screws will leak, like you said they're recessed. They had space for a cap they pressed in there.
There was a cap?! You learn something new everyday. I am about 3.5 hours from Lancaster.
There was a cap?! You learn something new everyday. I am about 3.5 hours from Lancaster.
Yes, they capped the air screws to stop people from adjusting the carbs.
Funny the A/F screws are only for idle it just seems that鈥檚 the reason they were capped because you really should not need to adjust them but every Vulcan I see had the caps removed
UPDATE:
I finally was able to get back to the shop. I got the 'new to me' air box installed and everything else put back together. I must have smashed a wire pretty good because it sounded like it was grounding out when I tried to start it. So, I took the gas tank back off and looked at everything. Nothing obvious, so I redressed all the cables making sure the loom tubing was protecting everything from ground. then I tried it again. The engine was trying to turn over so I put the gas tank back on and after turning it over a few times, it started no problem! It sounded good, it idled well, it revved great. I thought I was done and that I would be ridding in no time. But am not the mechanic I thought I was. The front carb is leaking pretty good. So I have to take everything back out. 馃槩 I did see a video by Andrew Roth, maybe? where he pulled the air box half way out and then lifted the back up with a ratchet strap to his ceiling joists. He was able to get the carbs out that way.

My new question for everyone, How do I test the carbs to see if they are leaking before I put them back in? Do just try and poor gas in to the inlets until it fills up? Do need to add vacuum to it some how?
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UPDATE:
I finally was able to get back to the shop. I got the 'new to me' air box installed and everything else put back together. I must have smashed a wire pretty good because it sounded like it was grounding out when I tried to start it. So, I took the gas tank back off and looked at everything. Nothing obvious, so I redressed all the cables making sure the loom tubing was protecting everything from ground. then I tried it again. The engine was trying to turn over so I put the gas tank back on and after turning it over a few times, it started no problem! It sounded good, it idled well, it revved great. I thought I was done and that I would be ridding in no time. But am not the mechanic I thought I was. The front carb is leaking pretty good. So I have to take everything back out. 馃槩 I did see a video by Andrew Roth, maybe? where he pulled the air box half way out and then lifted the back up with a ratchet strap to his ceiling joists. He was able to get the carbs out that way.

My new question for everyone, How do I test the carbs to see if they are leaking before I put them back in? Do just try and poor gas in to the inlets until it fills up? Do need to add vacuum to it some how?
A hose attached to a plastic bottle, fill the carbs up. They sell fuel bottles that will hang upside down like a medical IV bag.

Just something like a soap bottle and a fuel line from the bike can work.
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If they鈥檙e leaking, it most likely is the O-ring the one that goes around the plate for the float housing he got to get that lined up perfectly and don鈥檛 let gas get to it cause it鈥檒l swell it but that鈥檚 probably where it is leaking. Use new O-ring then you insurance issue.
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Don't feel bad, I broke my carburetor bracket pulling them the second round. I replaced the carbs with a used set from a 1993. Since then I am more careful on removing them. I getting pretty good a reinstalling the carbs now.
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