Author Topic: #1 cylinder not firing  (Read 1644 times)

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Toyman321

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#1 cylinder not firing
« on: October 27, 2006, 01:08:41 AM »
My #1 cylinder isn't firing, 2,3 and 4 are running fine. (73 cb500)I checked for spark and I'm getting spark. Plug's wet and I can smell unburnt fuel in the exhaust so I'm getting fuel. I'm thinking of shooting some starting fluid in the carb and see if I can get this thing running. Any other ideas? I've been standing over the thing scratching my head for the last 2 days.

Offline Bob Wessner

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Re: #1 cylinder not firing
« Reply #1 on: October 27, 2006, 02:03:08 AM »
It might be a stuck float, or a float valve not sealing properly because of some debris on the float valve seat.
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Offline 750goes

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Re: #1 cylinder not firing
« Reply #2 on: October 27, 2006, 03:26:23 AM »
check along the length of the plug wire, is it chafed anywhere, cracked, could be shorting out somewhere, whats the plug cap like also??,, swap the plug out see what happens??

Offline bryanj

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Re: #1 cylinder not firing
« Reply #3 on: October 27, 2006, 06:39:53 AM »
Definatelt swap the plug for a NEW one they can spark outside and yet fail under compression, check compression then go to the carb if all else is OK
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Offline OldSchool_IsCool

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Re: #1 cylinder not firing
« Reply #4 on: October 27, 2006, 12:45:22 PM »
On the pessimistic side, take off the valve adjustment caps for cyl #1 and confirm your valves return all the way.  A stuck or bent valve will allow your fuel gasses to escape before they sufficiently compress to explode.  It's a long shot, no doubt, because you would be getting backfire through the exhaust or carb if valve leak has gotten serious enough.  But it's also an easy check.
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Toyman321

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Re: #1 cylinder not firing
« Reply #5 on: October 30, 2006, 08:48:18 PM »
It might be a stuck float, or a float valve not sealing properly because of some debris on the float valve seat.

Winner.stuck float, can't believe I missed it, I've spent to long working on injected cars.

Thanks all for the help and suggestions!!