Engine question re unbalanced exhaust at start up and idle

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Michael Haener
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Engine question re unbalanced exhaust at start up and idle

#1 Post by Michael Haener »

Hi all,

I have a recently rebuilt (by me - my first) normal engine , completely stock, with a total of about 325 miles on it. The engine runs great and idles smooth at around 600 rpm. Although everything seems normal (ha) one thing I noticed is that in cold weather, upon start up and at idle, there is considerably more condensation “smoke” coming out of the right exhaust as opposed to the left. The imbalance is considerably less once the engine warms up. Anyone know what might be causing the initial imbalance?

The engine has had several oil changes but I have not yet adjusted the valves since doing so after the initial 1/2 hour run-in

Thanks in advance
Mike

Chuck Allard
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Re: Engine question re unbalanced exhaust at start up and id

#2 Post by Chuck Allard »

Carbs aren't quite synched. one is running too rich.

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Ron LaDow
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Re: Engine question re unbalanced exhaust at start up and id

#3 Post by Ron LaDow »

MichaelHaener wrote: The engine has had several oil changes but I have not yet adjusted the valves since doing so after the initial 1/2 hour run-in
Thanks in advance
Mike
You at least need a tune up.
Do a complete tune up, ALL of it, and do it in the correct sequence. The carbs are the last, as they are adjusted to conform with all of the other specified values.
Ron LaDow
www.precisionmatters.biz

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Michael Haener
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Re: Engine question re unbalanced exhaust at start up and id

#4 Post by Michael Haener »

Thanks chuck, though I don’t believe it’s a carb issue - the “smoke” is of the type you see upon initial start up all cars in cold weather. It’s more condensation than smoke and I don’t smell any I unburned fuel like one does when a car is running rich.

Thanks Ron, will do a complete tune up. I suspect a valve adjustment might clear up the issue, but I was really more curious to learn about the science behind what’s going on. Right side running slightly hotter than left? Or the opposite?

Thanks again
Mike

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Thomas Sottile
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Re: Engine question re unbalanced exhaust at start up and id

#5 Post by Thomas Sottile »

Forgetaboutit

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