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Smoking Tail Pipes


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Hello again everyone,


Thanks for all the help on my previous problems. I know this came up in my old thread, but I figured I'll start this over fresh since it was a second order issue.


Long story short is:


-Car sat for approximately 2 years.

-When I got it, the shipping company had messed with it a bit (swapped battery out for a crappy one, took some clamps, took some loose parts that were in it, and I think stole the fuel).

-New battery went in, but fuel wasn't getting through.

-replaced float pin assembly in the edelbrock carb.

-ran, moved...and I gave it an oil change because it started spitting oil out of the breather and because it had been so long.

-ran 10-15 minutes, no oil spitting...but had a double gasket on the oil filter, dumped oil, I shut it off instantly.

-second oil change, wouldn't start, fuel wasn't getting there again

-took the carb off, and used all the parts in the rebuild kit this time

-starts again as off today! :)


So...in this whole process every time it started and ran it would smoke. Always seems to start as heavy white, but will dissipate to where one tailpipe is clear and the other seems blue, but very very light smoke. (It is true dual exhaust) Half of my mind thinks if I run it long enough it will just dissipate out, but the other half of my mind is a little scared to run it very long.


Someone in my old thread did mention this could be a sign of worn valve stems. I kind of wrote that off because I had rebuilt the engine just prior to it being in storage. I had gotten assembled aftermarket aluminum heads. With the valves being metal, I'm just assuming they wouldn't wear out just sitting there. Please let me know if I'm wrong though.


How worried should I be about running it if its smoking lightly?

Is it common for an engine to smoke just because of how long its been sitting?

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It does sound like a valve issue. It's not so much that the valve itself leaks bit the valve stem seals themselves will, letting oil into the cylinder. Sitting for a prolonged period without starting it and running it can allow the seals to dry out.

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I would run it through a few heat cycles before I worried too much about it. Run it for several minutes after it is up to operating temperature, let it cool down completely, check the torque on the intake manifold bolts, check the oil and warm it up again a few times. It takes quite a while to get any oil burned out of the exhaust system.



“If you can't explain it simply, you don't understand it well enough.”

--Albert Einstein


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Seals and gaskets should be dry.

But also white smoke is a sigh of head gasket failiure. Blue smoke looks like oil burning.

Mustang, Mach 1 and 351

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The piston ring(s) could also be stuck in their groves in some of the pistons, especially on the cylinders where the valves were open.


If it sat for 2 years, there's no telling what could be up. Something could have made a nest in there...


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I'll probably try to run it a little more this weekend. An alternate theory someone else had mentioned is that some of my hydraulic lifters could be stuck and not closing the corresponding valve(s) properly. He had said running it might break them free if that was the case.


I did run it for a couple minutes since my last post. The only difference in my observations was that it started completely clear. Then on side started to sputter white smoke at a rate of about 3 puffs a second. The engine wasn't running as evenly as before, so I shut it down. Prior to that it had always been constant smoke. I'm not sure if that was an improvement or if that's a sign its getting worse.


I had thought about the head gasket, but I have no sign of mixing in my coolant or oil.

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Well, I ran her a couple times. Still smoking a bit, but settling down some. The idle is starting to settle a bit lower as well. I do think it is burning some oil, because it has a blueish tint to me; but it hasn't been enough to effect the oil level at all.


It does seem to puff thick pure white every now and then, but I haven't seen any indication of a blown head gasket in the fluids. It did ran here the other day, but I wouldn't expect that to effect a white puff after it's been running 5 minutes.


Only other note is that the carburetor seems to smoke a little bit after I shut it down. Mean anything?

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A thought I have is to check the PCV valve.


make sure it isn't plugged as it draws blow-by gasses

out of the crankcase.

73 Grande

351C 2v

Now 4v Carb/Cam/headers/T5


Gasoline is for washing parts.

Alcohol is for drinking.

Nitomethane is for racing!



Work in Progress photos here:

Last Update: 4/23/16

























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Oil smoke after sitting can be caused by valve stems rusting in the guides and then causing wear on the seals. It can also come from ring blow by through the PCV system.


If you have a vacuum gauge, then it can tell you some information on the condition of the valves seating, the ring seal and even indicators of a blown head gasket.




White smoke is usually water. While an accumulation in the exhaust system is normal, after reaching and maintaining normal temperature it should stop. Periodic puffs are an indicator that the water is still getting into the cylinder. This will not necessarily contaminate the oil.


I'd recommend you pull the plugs and look at each of them. If the oil is an issue you'll probably find one or two plugs that are fouled. If there is a bad head gasket, then a plug will generally be very white from the steam cleaning effect.



If the plugs are good, then I'd try running the engine on break in oil to see if you can get the rings free and reseated, but I would not expect this to make a huge difference.


I think you have either a bad head gasket (more likely) or a crack in a water jacket.



"I love my Hookers!" and "Get some Strange" probably have a different connotation to non automotive enthusiasts!

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  • 2 weeks later...

The white smoke indicates a possible head gasket the blue smoke could be anything that has to do with oil. I'd do a compression test on each cylinder to start also check the look and smell of the oil and coolant look for signs of oil in the antifreeze or visa versa, also look for bubbling in the radiator. My car sits for most of the winter and when I start it I get a little blue smoke but it clears very quickly. I figure since the engine has never been rebuilt that I'm getting a little oil past the valve stem but nothing that I'm willing to tear down a perfectly good running motor for. If I were getting the smoke you described I'd start checking for head gasket first then compression second. I'd also check that your carb is not flooding the engine with gas and washing the cylinder heads. I hope you find the problem and I hope this helps.

Going fast is fun but life is short so slow down and enjoy the ride :D Frank

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