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Old 05-30-2015, 10:01 PM   #1
ol'blu72
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Exhaust Smell From Only One Exhaust Pipe

So I have been doing some tuning and leaned the carb out a bit. It is running good but I am getting fuel smell from the right exhaust pipe. The left one does not have this smell. What could be going on??
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Old 05-30-2015, 10:11 PM   #2
Grumpy old man
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Re: Exhaust Smell From Only One Exhaust Pipe

Well... You can't lean out your carb by smell . It's done by rpm and vacuum lean to far and you start burning valves . your better to run rich and save your engine .Stop smelling your exhaust it's really not good for you and definetly kills brain cells .
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Old 05-30-2015, 10:28 PM   #3
ol'blu72
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Re: Exhaust Smell From Only One Exhaust Pipe

Quote:
Originally Posted by Grumpy old man View Post
Well... You can't lean out your carb by smell . It's done by rpm and vacuum lean to far and you start burning valves . your better to run rich and save your engine .Stop smelling your exhaust it's really not good for you and definetly kills brain cells .
Thank you for your input, but I am not asking how to tune, I am asking what could be causing a fuel smell from only one bank.
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Old 05-30-2015, 10:35 PM   #4
hugger6933
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Re: Exhaust Smell From Only One Exhaust Pipe

Check your plugs, if you have headers and a thermo gun shoot each tube to find the coldest one then pull that plug or check the wire to the hole. If you don't have a thermo gun [most don't, I use them to check the metal temp to know when I can paint among other things]drip a little water on each tube to see if it bubbles and burns off or not that one is hot is probably ok. The one that doesn't "fry" is where a good place to start looking. To smell as you say probably means as you know it is way fat. I don't mean Phat in the way the kids would say meaning cool either. Jim
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Old 05-30-2015, 10:38 PM   #5
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Re: Exhaust Smell From Only One Exhaust Pipe

Fouled plug ? burnt wire ? lazy lifter ? worn cam lobe ? improper carb adjustment ? the variables are untold .
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Old 05-30-2015, 10:45 PM   #6
ol'blu72
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Re: Exhaust Smell From Only One Exhaust Pipe

I do have a temp gun, I have ram horns and shot all the putputs and they were all around 220 except #6 which was about 320. Pulled the plugs one at a time and engine stumbled with each. Made sure the carb was even lt to rt (same jets, rods and idle screws).
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Old 05-30-2015, 10:56 PM   #7
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Re: Exhaust Smell From Only One Exhaust Pipe

There are still a lot of old style SUN gas engine analysers out there for sale cheap ,easier yet drop an x pipe into your exhaust and everything balances out fast .
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Old 05-31-2015, 12:12 AM   #8
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Re: Exhaust Smell From Only One Exhaust Pipe

Sticking heat riser valve, forcing most of the exhaust through one pipe?
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Old 05-31-2015, 07:27 AM   #9
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Re: Exhaust Smell From Only One Exhaust Pipe

Could it be a burnt oil smell? Could be getting past a bad ring or valve stem.
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Old 05-31-2015, 08:33 AM   #10
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Re: Exhaust Smell From Only One Exhaust Pipe

Look in the carb while it's running. Could be fuel dripping from the booster on only that side.
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Old 05-31-2015, 09:48 AM   #11
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Re: Exhaust Smell From Only One Exhaust Pipe

The temp gun method I mentioned will not be as effective on a manifold equipped engines because of the construction of the manifold. Hope you get it lined out. Jim
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