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Discussion Starter #1
My 62 194 6 cyl produces black sooty exhaust when first started and runs rough until warm then runs real smooth. I'm thinking worn valve stem seals allowing oil to run into combustion chamber when it sits over night or longer. If that's it I plan to replace seals with head still on engine using an air hold tool. Will this one work? https://www.amazon.com/Powerbuilt-648457-Valve-Holder-Hose/dp/B002IO0X26

It says it works for 14 mm and 18 mm spark plug holes?

I've never done this but it seems straight forward. Do I use stock stem seals? I've read a lot of posts about umbrella seals or something like that and I don't know what that is but then most of those are talking about after market and over sized valves etc.
 

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1970 Nova SS 350 Brandon, MS
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Normally, black sooty exhaust is too much fuel. Oil smoke is blue. I would look at the fuel delivery system for problems.
 

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Valve seals

My 62 194 6 cyl produces black sooty exhaust when first started and runs rough until warm then runs real smooth. I'm thinking worn valve stem seals allowing oil to run into combustion chamber when it sits over night or longer. If that's it I plan to replace seals with head still on engine using an air hold tool. Will this one work? https://www.amazon.com/Powerbuilt-648457-Valve-Holder-Hose/dp/B002IO0X26

It says it works for 14 mm and 18 mm spark plug holes?

I've never done this but it seems straight forward. Do I use stock stem seals? I've read a lot of posts about umbrella seals or something like that and I don't know what that is but then most of those are talking about after market and over sized valves etc.


Pull the carb off & rebuild it with a kit---the choke is set too rich or the pulloff isn't working. Don't waste your time & $ on valve seals. As stated above black sooty exhaust is rich fuel---blue smoke is oil consumption.:)
 

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Discussion Starter #4
I've adjusted the carb according to the manual and utubes I've seen. Also when it warms up it runs really nice. I could be wrong about the color of the smoke. When the stock exhaust was on it the pipe pointed to the ground behind the left wheel. I would get a big black spot on the drive way but I never paid attention to the color of the smoke. Now the exhaust is cut off just past the muffler. I've been restoring it for several years and need to get an exhaust pipe put on it.

I don't mind rebuilding the carb but I don't have a great track record with that. I always seem to make them worse!
 

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Sounds like the choke is set too rich. If the valve seals were bad, you'd get that smoke at other times when you drove and oil is up in the valve train. Black smoke and soot (I know that black spot on the garage floor) is usually choke setting.

If it runs well and doesn't smoke when warm or on deceleration, then it's likely not the valve seals.
 
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