Author Topic: 79 cb650 #2 cylinder no fuel help!!!  (Read 669 times)

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Offline 79custom

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79 cb650 #2 cylinder no fuel help!!!
« on: August 12, 2014, 05:53:32 PM »
I have had my 79 custom for about 8 years and i never really had a problem with it, then it sat in storage for 2 years while i was away. when i got back she wouldn't start barely at all and it had a few problems, i didn't have the time to fix it so i took it to a shop where they fixed it? then let it sit for a few months. just got back on it yesterday no problems on start up or running didn't think anything of it until i went to check why i was not getting as much low end power and i found out my #2 cylinder is not running (pipe and head cool to touch after running).

i checked the plugs all good tons of spark even swapped #2 and #3 cables on same coil no problem #2 ran #3 just fine, no change in power or idle. replaced plugs anyways for good measure.

I checked compression, i have lots of compression in all cylinders about 115psi give or take 5psi.

the only thing i could find is the sparkplug when i replaced it with new it still came out hot and dry no smell of fuel and totally dry. i think my #2 cylinder isn't getting fuel. could it be the #2 carb, i have heard a lot about them flooding the throat and cylinder but i haven't heard much about them starving the cylinder or how to resolve it. any idea what it could be or where i should go from here? i will take the carbs off tomorrow or the weekend when i get the time its a real PITA. any ideas what it could be or how to resolve it?

Offline calj737

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Re: 79 cb650 #2 cylinder no fuel help!!!
« Reply #1 on: August 12, 2014, 05:58:39 PM »
Easy to check. Open the drain on the bottom of the bowl and catch what gas comes out. Measure it against any adjacent carb.

Then, open the petcock and repeat to verify fuel is flowing to carb. If not, likely culprit is debris or gunk has clogged your jets from sitting. Time to drop the bowl and clean that baby if that proves to be your situation.

Hint: if you need to let the bike sit for prolonged periods, run the carbs dry by closing the petcock and this will empty the bowl (mostly) or use some type of fuel additive to prevent extra corrosion from occurring.
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Offline 79custom

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Re: 79 cb650 #2 cylinder no fuel help!!!
« Reply #2 on: August 12, 2014, 06:04:00 PM »
thanks that sounds like a good lunch-time project tomorrow, il see if that fixes the issue or points me down the yellow brick road of carb cleaning. :)