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Smoky exhaust upon starting

A couple of weeks ago there was a discussion about a car that smoked badly when it started. The boys recommended trying some oil additive that might avoid a ring job. Does anybody remember or know what this product was?

There are lots of different brands at any parts store.

I didn’t hear the discussion, but generally when a car smokes upon startup the valve stem seals are the first suspect. While the car is sitting, the oil from the heads gets past worn valve stem seals and sits on the backs of the valves and/or in the cylinders and when the engine gets started it gets burned and blown out the exhaust. It’s a common problem.

The oil Additives are sold on at parts stores that allege to restore valve stem seals (as well as other seal leaks like front mains)/ How well they work, I don’t know, but on an old beater they’re worth trying.

Can you describe the problem you’re having?