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First gen FB smokes on a cold start

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Old Mar 26, 2015 | 09:24 AM
  #1  
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First gen FB smokes on a cold start

My '81 fb sends out a nice big cloud of blue smoke when I first start it with the choke. Is this a sign that the valves rings or something are going out and is there a way to replace them/fix this issue? Or is it just the engine running a little rich and nothing to worry about... The car doesn't smoke other than the first 10 seconds it runs when it's cold.
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Old Mar 27, 2015 | 09:42 AM
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Same thing happens to mine, I believe its just the engine warming up. Don't think it means anything is wrong.
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Old Mar 29, 2015 | 08:49 AM
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One of the cool things about a rotary engine is that it does not have any valves, so that's not it. It could be that it's a bit rich, or it could be that your oil control rings are getting bit worn, but since it's only upon startup it isn't a big deal so I wouldn't worry about it.

If you spend a little time on the 1st gen section you'll find a lot of threads about it.

Welcome to the forum!
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Old Mar 29, 2015 | 10:11 AM
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It is quite common for a rotary with a little wear on it to smoke a bit on startup.

As there are no valve seals to leak, that's not it. But in a way, the issue is sort of similar. When the engine stops rotating the rotors are now full of pools of cooling oil, now stationary. That oil pools around the oil rings that seal the center of the rotor from the combustion area. With some wear, and the oil thinning effect by a little residual fuel in the chamber (especially carb'd vehicles as turning off the key only cuts ignition, the engine continues to suck as it spins down), some of that oil can bypass the seals as the car sits.

Then on next startup, it burns off.

So it's not something really to worry about unless the engine begins to smoke at low RPM/idle.
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Old Mar 30, 2015 | 10:06 AM
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Thanks for the info/help guys. I'm a noob at rotaries at this point so I appreciate the input.
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