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How do I tell when I'm lean/rich?

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Old 08-21-2013, 08:07 AM
  #1  
cashbgtp97
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Default How do I tell when I'm lean/rich?

I do enjoy my beef lean and my wallet rich but when it comes to this 1967 mustang i am pretty sure neither are beneficial. The big question is how can i tell whether i'm running lean or rich (yes, silly question cause i really don't know.. *sad face*)?

Once I figure out whether I am running rich or lean what adjustments do I need to make in order to correct this?

Currently I start her up, she spits out blueish white smoke while idling (warming up) then when she's warm and i drive around the smoke is a little clearer but still there. it has a bitter smell to it, smells old/stale.

Thanks for the info!

-cash
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Old 08-21-2013, 08:30 AM
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paddy187@hotmail.com
 
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Cash,

I heard it is better to be on the rich side than the lean, I am sure some one will correct me if I am wrong. Follow the manual for the carb and u should not be far out, especially as u are at see level. If you have not adjusted in a long time your spark plug colour and condition can help you out.
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Old 08-21-2013, 08:50 AM
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dawson1112
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Blue smoke indicates your burning oil. If It was rich It would be blowing some black smoke. If it was lean there would be excessive popping in the exhaust and it may even get hot.

You probly have a valve seal leaking a little oil into the cylinders.
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Old 08-21-2013, 10:41 AM
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67mustang302
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Yup, sounds like oil burning.

As for the AFR, only real way to tell is look at the plugs or use an AFR gauge....and even AFR gauges can lie to you sometimes.
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Old 08-22-2013, 09:14 AM
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69thunder
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Yeah bluish "stale smelling" is likely oil burning. You probably have some bad guides or rings. Possibly have some strange contaminants in the fuel but more likely oil burning. You probably should address why it is burning oil before worrying about whether it is slightly rich or lean.
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Old 08-22-2013, 10:03 AM
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69mach1377
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They can be related...running too lean will cause too much heat and early wear, leading to burning oil. Better rich than lean.
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Old 08-22-2013, 11:25 AM
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cashbgtp97
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I am just car-sitting the coupe until april (so i've got time) and the guy who actually owns it told me that he thinks he needs an o-ring on the oil drain plug. any reason he might need that or would it be better to just replace the drain plug. there is definitely leaking (as i can clearly see the oil stains on the driveway). possibly oil pan gasket?

I am also concerned with what appears to be oil or some kind of liquid on TOP of the intake manifold (just under the carb). bad manifold gasket? head gasket?

-cash
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Old 08-23-2013, 09:51 AM
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69mach1377
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O-ring? Maybe a copper washer...finding an oil leak can be a challenge, so don't assume without much cleaning and rechecking.
Carbs can 'ooze' when left to sit a long time. The only gaskets involved here are the carb base gasket and carb gaskets themselves.
These things happen to old cars not driven regularly.
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Old 08-23-2013, 10:30 AM
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cashbgtp97
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Sounds good. guess i'll have to jack her up and spend some quality time scrubbig her undercarraige so i can see where the leak is coming from. I really don't understand why oil would leak from the oil drain plug but i guess i'll find out.

ya i dont' understand why he thought there is supposed to be an o-ring around the oil drain plug. i would have guessed a washer or just replacing the plug. again i guess we'll find out!
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