dead cylinder

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likembikem

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Apr 7, 2011
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Location
Hillsboro,Tn.
Mine is a 2001 bought a year and half ago with 3k miles. Previous owner had died, who knows how long it had sit. It has never had the go my '97 had, but did run pretty well; most of the time. i had an exhaust header cool to the touch and cleaned carb by spraying cleaner down the throat and pulled the diapham and sprayed cleaner, problem went away. Then recently started running bad on another cylinder (cool to touch) I found rust in the tank and replaced tank and filter. i have good spark. i opened all the drain screws and drained the bowls. But the one that was not running had no fuel come out, removing the screw completly some fuel came out but not much. Is there something I can do without pulling the carbs out? I'm afraid I would open a can... I have a tank of the 'start your engine' in it now. I wonder if it is gunk or rust. How does rust get past the filter? I checked the sync and all the same, can you have a good sync even if no fuel is flowing? I never heard of the float sticking up causing no flow, seems they always stick with full flow. I'm about ready to take it to a dealer and let them have at it. The constant cleaning, running seafoam and dead cylinders are getting old, Is this the same crappy carb problems that are common the vmax or am I missing something simple?:bang head:
 
One more thing; anyone ever use one of those laser, infrared temp reading things that you point and get a temp reading? looks like that would be a good cylinder health indicator.
 
You could try "Start Your Engine". It comes in a very small bottle, can be bought at auto parts stores and works better than anything I've ever seen. Read the instructions, you need to mix it as directed...

I have one of those lasers from Harbor Freight, $29.95. It works great to see how even the exhaust temperature is as it leaves the heads...

Good Luck,
Dave
 
Yes I have some of the 'start your engine' in the tank now. Going on a 10 mile ride to see how it does, then if it doesn't work (which I feel like it won't) I'm going to remove my air box and see if If I can see a kinked hose or something. I did the propane gas tip around my fittings with no RPM change. I will have one of those Harbor Freight temp readers, can't beat the price. thanks
 
Very tiny rust particals or "dust" can make it past the filter, then collect in your carb bowls and cause problems. If your previous tank had rust in it and was replaced, chances are the carbs could stand to be disassembled and thoroughly cleaned. Go to the carb section of this forum and check out the step by step sticky's on how to easily do it.
 
Your carbs need going through, period.

There are a few complete working racks of carbs for sale by members here right now, maybe you can work out an exchange deal. Swapping them is super easy.
 
You mean cleaned up renewed carb rack. Won't they still need to be adjusted? I'll check around on the site for replacement. I thought it might come down to this, I was hoping not to. I did find my jet 2 was gummed today, amber colored obstruction, used cleaner and air and it was clean. thought that might do it but no. Fuel still does not come out the drain line when opening drain screw. Take the screw out and fuel comes out. tried cleaning the drain tube to no avail. I hope i don't miss too much riding time. thanks for your help...Mark
 
Yea I do mean s/h racks, in good working condition. The only adjustment you should really need is to sync them on the bike - a 5mn job with a vacuum gauge.

Head to the Carb/tuning sub-forum for full info.
 
All the above is good advice. Your needles are prob a bit sticky from gum buildup and prob wont come clean without getting in there. Plus I didn't hear any mention of replacing the filter. Do so if you didn't already.

And +1 one on the lazer temp readings. I use mine alot for diagnosing. Hit the same spots on exhaust pipes right where they exit the jugs.
 
Yes, I replaced filter when i replaced tank. I'm getting ready to pull the whole mess and bench clean them. I'm sure I will be back here before I get finished!
 
Took out carbs this evening. The one that was causing so much trouble had a lot of rusty junk in the bowl. Cleaned out the enricher, the jets, and blew air through everything. Did all of them. Put them back on and started, without the breather box installed and seemed like my dead cylinder was still dead! started fiddling with the sync screws and it came alive, I synced with out the breather box and seemed the bad cyl. started heating up. I still not sure, had to come in to clean up and get ready for an early work day tommorow. BTW your pictures were a huge help. I had to use an impact to break the big phillips. I would not have tried this without you guys help. Dealer said around $750 to do the job and might be a month. I'll get a fresh start tommorow and see what I've got
 
Glad to be of help. Rust in the carb bowl, hmm.. Did you remove/clean everything after replacing your tank? You might have residue if you didn't. Take a good look at your fuel filter - make sure it's completely clean now. Then I would make absolutely sure that the fuel pump and all the fuel hoses between the tank and the carbs are also completely clean and free of debris.
Nothing like compressed air to blow them clean - and a bit of carb cleaner if there's anything in there.
 
Cleaned fuel lines with cleaner and air. New fuel filter (replaced twice). I did turn the key on with fuel line disconected and fuel spayed. Not sure how clean it was as it went across the garage floor. I'm hoping with air box and air filter it is running fine. I wll know for sure this evening. I was amazed at how smooth the engine can be even with one cyclinder not firing. If this doesn't take care of the problem, I'm pulling them off again. I'll let ya know!
 
When you crank it with fuel lines disconnected, stick the end of the fuel hose into a white or clear glass container - best way to look at the fuel (and reuse it too :)

Good luck!
 
Bike was still running on 1 cyl today. Removed carbs again and found more rust in the bowl. Recleaned everything and tried again, this time things were worse! After careful study I found one of the sync screw springs was on the wrong side of the tab. This seemed to be holding one of the butterfly valves open,some. Also the choke shaft white nylon bushing was on wrong. Aligned the carbs unit and adj. butterfly valve/ sync screws to get all closed. throttle operation seems smooth and choke seems smooth and works. Well gotta get ready for work so I will try it all tommorow. BTW Nasty; I got on the computer at work and your exellent pictures and write up of the carb clean/rebuild had everything I needed...so I hit print. Then stood around the printer waiting for it to finish. I looked down and saw "Page 19 of 128" crap, well I'm already into it, so let it go. A few noticed and asked about it, I blew it off and refilled the paper, with a "replace toner" flashing. It's tough sometimes!
 
Done: All cylinders running. Synced up and smooth. I will have to pull my left side scoop and check routing of throttle cables. Doesn't seem to snap back closed like I think it should, or like it did before. That ain't nothing.... Thanks for the help!
 
Glad you got it sorted! Do check your float bowls contents again though - you really don't want any rust dust in there..

For the throttle, check the box on the left where the cable links are, should be well lubricated with silicon grease or similar. Also check the cables are going properly to the carbs, I've made that mistake before. Also check the RH controls on the bars haven't been tighten too far toward the speedo - that makes the end of the grips stick to the metal of the bars.
 
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